The Dog Zombie

Classical conditioning: do try this at home

2012-01-11T19:22:00.000-05:00

In What is classical conditioning? (And why does it matter?), Jason Goldman asks, “Can you think of other real-world examples of classical conditioning?” Dog training, Jason! I can’t believe you missed it — beyond talking about Pavlov, who wasn’t really a dog trainer. How useful is it really to teach a dog to drool?

I used classical conditioning on my dog Jenny a few minutes before writing this post. She is in the process of developing an ear infection, but she hates to have her ears cleaned. I’m using classical conditioning to change her emotional reaction to the ear cleaner from fear or stress to anticipation and enthusiasm.

The unconditional stimulus (UCS) is the ear cleaner. When I show it to her, she has a natural response (fear, demonstrated by her sudden flight from my vicinity). I could pair this UCS (ear cleaner) with a neutral stimulus (a bell). The animal learns to apply its emotional response to the second stimulus (fear of the ear cleaner) to the first stimulus (the bell). In other words, the bell comes to predict the ear cleaner, and eventually, the dog would learn to run away when she heard the bell, as if she were afraid of the bell.

That’s not useful either. What I am doing is pairing something to which Jenny has a positive natural response (cheese) with the ear cleaner. The first thing she sees predicts the second thing, so I show her the ear cleaner first, then give her cheese. Over time, the ear cleaner comes to predict cheese, and eventually she will greet the ear cleaner with the enthusiasm previously reserved for cheddar. Of course, I have to build slowly up to actually cleaning her ears, but after one session she is enthusiastically touching her nose to the bottle when I show it to her instead of leaving the room. I expect the process to take several sessions, so I’m starting before I actually need to clean her ears.

Classical conditioning is also used frequently in behavior modification, to change the emotional response (fear) of dogs to a stimulus (strange people, strange dogs) into a new emotional response (enthusiasm). Again, pairing food with the approach of the stimulus works well, with a sufficiently gradual approach. This counter-conditioning approach is frequently used in the behavioral treatment of dogs who erupt into enraged barking at the sight of other dogs.

It is important to remember that the first stimulus predicts the second. If you get things backwards, you can break your dog! I have heard stories of people teaching their dogs to flee the room upon smelling peanut butter, because peanut butter had been overused as a lure before a variety of unpleasant stimuli (ear cleaning, nail clipping...). So remember, bad thing first, good thing second.

Go, try it if you have trouble cleaning your dog’s ears or clipping their nails!

[ETA: There is some very interesting discussion about the definition of classical conditioning in the comments. -DZ]

The hearty ingredients of Canis soup

2011-12-31T06:37:00.000-05:00

[Reposted from my post on Scientific American’s guest blog.]

The wolf is iconic and charismatic. We see him on t-shirts, on posters, and in fantasy novels. Conservationists do battle with ranchers to preserve populations of wolves. The coyote, on the other hand, is neither iconic nor loved. A newcomer to suburbia, he is feared as a suspected predator of cats, small dogs, and even small children. He is rarely seen on t-shirts; his name is not used to designate a rank of Boy Scout.

But now that we have the genetic tools to look at these animals’ genomes, it turns out that many of the populations of coyotes in North America are actually coyote-wolf hybrids, as are many of the populations of wolves. Unable to draw clear lines between these species, biologists have dubbed the populations of hybrids “Canis soup.”

What’s a Canis?

The term “canid soup” has also been used for this mess of wolf, coyote, and even dog genes that we find in some populations of canids. So what does Canis mean, and what is a canid?

These are terms related to the scientific classification of the species in question. Going through the hierarchy, we have Kingdom Animalia, Phylum Chordata, Class Mammalia, Order Carnivora, Family Canidae (canids), and Genus Canis. Wolves, dogs, jackals, and foxes belong to the family Canidae, but only wolves, dogs, and jackals (not foxes) belong to the genus Canis. We call the wolf-like canids “canines” and the fox-like canids “vulpines.”

As foxes do not interbreed with wolves, dogs, or jackals, what we’re talking about here is correctly Canis soup, or perhaps canine soup, but not canid soup.

Is it Canis or is it soup?

The more you dig into wild canines in North America, the more unclear it is where any species lines should be drawn. So who makes up our cast of characters?

Gray wolf
(Image courtesy of Wikipedia)

The first ingredient in Canis soup is the charismatic North American gray wolf or timber wolf, Canis lupus, sometimes known as Canis lupus lupus to differentiate him from the dog and the dingo, who belong to subspecies. The gray wolf is the largest wild canine, at a 79 pound (36 kg) average weight. (Domestic dogs of some breeds, of course, weigh more than that.) His coat coloring can vary from white through blond, brown, grey, and black. He is found in the western parts of North America.

Western coyote
(Image courtesy of Wikipedia)

Next is the Western coyote, Canis latrans. This animal is also known as the American jackal or prairie wolf, suggesting that there has been some confusion about how to distinguish canine species for some time. The Western coyote is a significantly smaller animal than the gray wolf, weighing in closer to 20 pounds (7-14 kg). His coat color is less varied than the gray wolf’s, almost always a grey-brown as you see in the image here.

Eastern wolf
(Image courtesy of Wikipedia)

The range of the Eastern wolf or Algonquin wolf, Canis lycaon, is Ontario, Canada. This wolf is smaller than the gray wolf, and has a distinctive grey-red coat with black hairs along his back. We believe that this wolf was the original North American canine, and that Canis lupus and Canis latrans immigrated over the land bridge from Europe. There’s a lot of debate about the species status of C. lycaon, as many Eastern wolves appear to have significant C. latrans heritage. Some people suggest that the Eastern wolf is in fact a C. lupus/C. latrans hybrid, or, alternately, a subspecies of the gray wolf, C. lupus lycaon.

Eastern coyote/coywolf
(Image linked from
Eastern Coyote Research)

The Eastern coyote, spreading along the east coast of the United States, is significantly larger than his Western counterpart. He turns out to be a coyote/wolf hybrid, and it has been argued that he should more accurately be called a coywolf. His wolf ancestors seem to be Canis lycaon — but then again, there is debate about whether C. lycaon is really different from C. lupus at all.

Red wolf
(image linked from True Wild Life)

The red wolf or Southeastern wolf is subject to truly intense debate about species status. Is he his own species, Canis rufus? A subset of the gray wolf, Canis lupus rufus? Or a population of Eastern wolf, Canis lycaon? He has a beautiful red coat, and is smaller in size than the gray wolf. His range was historically the southeastern U.S., but he went extinct in the wild by 1980. A founder population of 19 animals survived in captivity, and a reintroduction project in North Carolina was begun in 1987. Here the red wolf is today enthusiastically interbreeding with coyotes, leaving conservationists to wonder what they are conserving.

The three species of wild canines in North America today, then, are Canis lupus, Canis latrans, and Canis lycaon. But we really have just two soup ingredients, wolf and coyote. There are pure wolves (Canis lupus) and there are pure coyotes (Canis latrans), and there are populations that are mixtures of more or less wolf and more or less coyote (Eastern wolves, Eastern coyotes, and red wolves). There appears to be some dog mixed in there, too. You can think of gray wolf and Western coyote as ingredients, and everything else as soup.

Coyote flavor versus wolf flavor

The 2011 paper “A genome-wide perspective on the evolutionary history of enigmatic wolf-like canids” analyzed the various soup flavors out there and presented their findings in some easy-to-understand charts (below). Here, the different colors represent different amounts of each ingredient. The first chart describes the Eastern wolf, here referred to as the Algonquin wolf, which is mostly gray wolf (green) and joint wolf/coyote (yellow), but also has significant coyote (red). The second chart describes the red wolf; at a glance, it is obvious that the red wolf has a much larger percentage of coyote genes (again, red in this chart). These charts both use τ to denote the number of generations since the most recent admixture with another species.

Two recipes for wolf flavored Canis soup
(vonHoldt, 2011)

The two coyote recipes pictured below describe two subpopulations of what I have described as the Eastern coyote; this particular paper considers them split into Northeastern and Southeastern coyotes. At a glance, these populations are mainly pure coyote (red), with big dashes of mixed coyote/wolf (yellow), and small but notable amounts of our friend the dog (dark blue, light blue, and pink).

Two recipes for coyote flavored Canis soup
(vonHoldt, 2011)

Wild canine populations challenge us to let go of our obsessive need to categorize. Instead of slotting a canine population into a single species category, we might instead think of it as existing on a spectrum from “wolf-like” to “coyote-like.” A strongly wolf-like canid would be larger, sixty to ninety pounds. He would require a larger range, and would be a deerivore, subsisting off of larger game. He is likely to be a shyer animal, found only in more rural or wild areas. Conversely, a strongly coyote-like canid would be much smaller, fifteen to thirty pounds, with a smaller range. He might eat deer as well as rabbits and et cetera (probably a lot of et cetera, as coyotes are more willing to scrounge than wolves are). He would be more likely to be found in suburban areas, with a greater tolerance for human proximity. A given population of canines might fall anywhere on the spectrum between the two. The fact that a spectrum actually exists is beautifully demonstrated by the Eastern coyote, who has mixed coyote/wolf ancestry, is mid-sized between coyote and wolf, and has a mid-sized range.

What’s your preferred flavor?

Does the intermixture of various ingredients in the formation of soupy populations matter as more than a gee-whiz story? To some people, the answer is very much yes. The conservationists who are committing significant resources to the preservation of the red wolf don’t want to see the wolves that they reintroduce interbreed with coyotes. If the reintroduced wolf population blends into a coyote population, then are these resources actually being spent just to support a bunch of coyotes (who have been doing fine on their own)? At the same time, evidence shows that the founder population of 19 red wolves was already significantly coyotified, and we’re not sure how long it’s been since there have been any pure Canis rufus specimens in North America.

It is, of course, possible to think about the problem without asking for genetics to provide the complete answer for us. The red wolf is a red wolf, a beautiful, iconic animal that has lived in the southeastern United States throughout living memory. We know what the red wolf looks like (and that hasn’t been changing much, no matter what is happening to his genes). We also know that he is important in a particular environmental niche, and that hasn’t been changing much either.

Practically, the mixture of coyote genes into fragile wolf populations may be a good thing. Because coyotes are better at living on smaller ranges and in closer proximity to humans than wolves are, they are better adapted to the realities of North America today. As their genes mix into wolf populations, these populations become demonstrably more robust, more able to tolerate human presence, and able to survive on smaller ranges. It is possible, in fact, that coyote genes are exactly what are eventually going to allow a red wolf population to flourish without human assistance.

Conclusions, if we can make any

Does it matter that some of what we think of as wolves have coyote genes? I think the answer comes down to a cultural perception of the wolf as a romantic and charismatic creature, and of the coyote as a pest. Perhaps any mixture of the two is perceived as diminishing the wolf. A friend of mine once made this analogy: if you have an entire bottle of fine wine, and you pour just a teaspoon of sewage into it, now you have a bottle of sewage. Does any amount of coyote, no matter how miniscule, make the wolf impure, and less worth conserving than it was?

As a culture, I hope we can come to appreciate the strengths that the coyote brings to Canis soup, in his ability to coexist with humans in the modern world. He may be what saves populations of charismatic wolves from permanent loss. As we look at populations of canines in North America, we should learn to say that one is more coyote-like and another more wolf-like, on a spectrum from one flavor of soup to another, and appreciate the benefits of both.

Canis soup has been used before as an example of the blurriness of some species lines and the inadequacy of many existing definitions of a species, but it also provides some interesting insights into the fluidity of canid morphology and behavioral characteristics. How did something as large and wild as a wolf become something as variably-sized and tame as a dog? Moreover, how did this change happen (presumably) without a carefully planned breeding program? Why is it so easy to breed types of dogs with such different behavioral and physical characteristics, especially compared to the much more limited variety of breeds of cat, horse, or cow? The canine genome clearly has the capacity for expression across a startlingly wide array of phenotypes. The evidence of this variety has always been right before our eyes, but we are just beginning to understand its implications.

References

Adams, J., Leonard, J., & Waits, L. (2003). Widespread occurrence of a domestic dog mitochondrial DNA haplotype in southeastern US coyotes Molecular Ecology, 12 (2), 541-546 DOI: 10.1046/j.1365-294X.2003.01708.x

Adams, J., Kelly, B., & Waits, L. (2003). Using faecal DNA sampling and GIS to monitor hybridization between red wolves (Canis rufus) and coyotes (Canis latrans) Molecular Ecology, 12 (8), 2175-2186 DOI: 10.1046/j.1365-294X.2003.01895.x

Hailer, F., & Leonard, J. (2008). Hybridization among Three Native North American Canis Species in a Region of Natural Sympatry PLoS ONE, 3 (10) DOI: 10.1371/journal.pone.0003333

vonHoldt, B., Pollinger, J., Earl, D., Knowles, J., Boyko, A., Parker, H., Geffen, E., Pilot, M., Jedrzejewski, W., Jedrzejewska, B., Sidorovich, V., Greco, C., Randi, E., Musiani, M., Kays, R., Bustamante, C., Ostrander, E., Novembre, J., & Wayne, R. (2011). A genome-wide perspective on the evolutionary history of enigmatic wolf-like canids Genome Research, 21 (8), 1294-1305 DOI: 10.1101/gr.116301.110

Way, J., Rutledge, L., Wheeldon, T., & White, B. (2010). Genetic Characterization of Eastern “Coyotes” in Eastern Massachusetts Northeastern Naturalist, 17 (2), 189-204 DOI: 10.1656/045.017.0202

Wilson, P., Grewal, S., Mallory, F., & White, B. (2009). Genetic Characterization of Hybrid Wolves across Ontario Journal of Heredity, 100 (Supplement 1) DOI: 10.1093/jhered/esp034

Zimmer C (2008). What is a species? Scientific American, 298 (6), 72-9 PMID: 18642545

Book review: Control unleashed

2011-12-21T16:36:00.000-05:00

I recently finished Control Unleashed: Creating a focused and confident dog, by Leslie McDevitt. This book is designed for people training dogs in agility who are having issues with their dogs’ ability to focus, so you might imagine that the book isn’t useful to people with fearful dogs like mine. But it turns out, unsurprisingly, that if your dog is having issues focusing, he may well actually be nervous about something in his environment, such as strange people or other dogs. This book is full of exercises for helping your dog be more comfortable and relaxed, whatever his reason for being distractable. It was incredibly helpful to me in thinking through exercises for my shy dog Jenny, to help her learn to trust the world a little more. Even if you don’t do agility with your dog, this book may be helpful in making you a better trainer. It includes many examples of specific training exercises to try, and stories about situations in which they were particularly helpful. It was also an enjoyable enough read that I got through it while working long hours on some difficult rotations — I looked forward to finding ten minutes to read it before bed. I recommend this book to everyone who has has basic understanding of positive training and learning theory, and wants to learn more.

I have become a chef. For owls

2011-12-04T11:47:00.001-05:00

Some days it seems like none of your patients will eat. I asked the intern at the wildlife clinic where I was doing a two week rotation what his advice was for convincing the tiny screech owl (214 grams of cute) to actually ingest food on her own. We had tube fed her; this worked, but you don’t really want to have to do it every day, and she really doesn’t want you to do it every day. We had force-fed her mouse bits with tongs, which was even worse. The intern suggested peeling the skin off of baby mice “so she can see the meat.“

Awesome.

In vet school, you get a little inured to gross things. I cut up mice for raptors every day on this rotation without getting squeamish. But I found peeling the skin off of two day old mice (thankfully already dead) to be a bit much. The intern was a little bewildered by my reaction. Anyways, it didn’t work.

The next day I went to a different vet for advice. “Sometimes,” she said, “they like to have the mice split open and the liver displayed... You can leave the skin on.” I did this. I was artistic about it. HERE ARE THE LIVERS. PLEASE EAT THEM.

And that night, she ate.

My next problem patients were two barred owls who had recently been transported a fairly long distance, which we were examining before they were placed into permanent captivity, as they were not releasable. These guys really didn't want to eat. I laid the mice out enticingly next to a branch on the ground. I split them open and DISPLAYED THE LIVERS. No.

The intern said, “They don’t want to come off their perch. They’re scared. Put the mice on the perch.” Easier said than done (he said it, I did it). One of the owls inevitably reacted to my entry into the pen with OH HOLY CRAP I AM GOING TO DIE, flying back and forth at high speeds. It wasn’t a very big pen. I covered my head with my arms and crept at a snail’s pace towards the perch. Veeeeery slowly I balanced the mice on the perch. And crept away again. That night, the owls ate.

The next day, as I was artistically displaying peeled mouse haunch for an Eastern box turtle (the mealworms weren’t working as they would just escape into his cage and set up shop there) I thought to myself: how did this become my life?

Dogs and babies

2011-11-26T17:22:00.001-05:00

Today I heard this sad story third-hand: as a baby is crawling away from Grandma’s dog, who has always been fine with him before, the dog without any warning pounces on the baby and bites him. The baby loses part of an ear and has deep wounds on his face. The dog is euthanized. The parents were there to supervise, but it all happened too fast to prevent. What went wrong?

The first thing I want to say is that at the point that a dog bites a child (or any human) this badly, I agree that the dog must be euthanized. He is not safe. For this reason, it’s really important to figure out how to keep this situation from happening in the first place, for the sake of the baby and the dog.

What was going on in that dog’s head? We can’t know for sure, but it sounds to me as though the dog was treating the baby like prey. He pounced when the baby was moving away from him, and he bit to injure. If he had been trying to play with the baby, he might have bitten hard enough to bruise, but dogs have excellent control of their teeth, and a bite bad enough to remove part of an ear was probably intentional. The fact that the baby was moving away from him at the time is supportive evidence — the sight of something small and helpless, which makes high-pitched noises and moves erratically, running away from him may have triggered him to act.

Do dogs really act like predators around babies, even if they know them? Some dogs, not all. I would be particularly suspicious of dogs with high prey drives — dogs who are obsessive about chasing small animals outside. They may learn to like small animals who are part of the family, like cats, but with dogs like this, I would be very careful with my introductions. In the case of a human infant, I wouldn’t leave the baby on the floor with the dog loose in the same room unless I really, really trusted the dog. I live with four good dogs who get along just fine with cats, but there is only one of them that I would trust with a baby on the floor. The price is just too high if you make a mistake.

How can you prevent such a situation, since the dog gave no warning signs? I was not there, but I can almost guarantee you that the dog did give warning signs; his owner was just not trained to read and understand them. The dog probably did subtle things like stare at the baby a little too long or sniff it a little too aggressively — things that wouldn’t make the average dog owner think twice, but would make the average dog trainer extra cautious.

So what do you do if you’re expecting a baby and you have a dog? Or if you are a grandmother and want your grandchild and your dog to get along? The safest and easiest answer is to not let the dog and child interact until you know you can trust them together. Put them together for short periods of time only, while you are holding the child, and observe the dog closely. Don’t leave them on the floor together until you are confident that the dog will ignore the child and that the dog shows no stress, fear, or predatory behaviors around the child. If you don’t think you can read the dog well enough to tell, hire a dog trainer to evaluate your dog. A dog trainer can help guess what problems your dog might have around a child, tell you specific signs to look for, be a resource to ask questions, give you tips on how to manage them together. To find a certified dog trainer in your area, search on the Association of Pet Dog Trainers site.

Dogs and kids can get along great, if they are introduced carefully, and when the kid is old enough. But the consequences of a bad relationship between the two are so serious that it is very important to take those introductions seriously, and to make sure you’re seeing things from your dog’s point of view before you assume everything’s okay.

The cat in the tree

2011-11-20T12:18:00.001-05:00

The skinny little tree was only about 30 feet tall and growing in the middle of a swamp. Recent flooding had surrounded it with water several feet deep. And yet somehow an orange cat had managed to climb it. He was perched precariously: when I first saw him, he was jammed into the fork of two branches, and his every movement made the little tree bend. I was riding with an animal rescue service, and we had been called out to get the cat out of the tree. It was supposed to be a simple job of using climbing gear to get up the tree; the rescue driver was trained to do jobs like this. But this tree was never going to bear her weight. It could barely hold the cat. Even getting to the tree was going to involve wading through waist-deep water in the chilly November weather.

The cat was glad to see us. He made eye contact and meowed, clearly asking for help. But it was not immediately clear how to help him. We talked about our options, and eventually decided that we were going to have to call back to the shelter for assistance. The rescue driver called her boss, but initially failed to convince him that she couldn’t just climb the tree. She eventually had to photograph the situation on her phone and send him that as proof that the tree couldn’t support a ladder, and that trying would just knock the cat off so that he would fall 30 feet into the cold water.

As we watched and talked about what to do, took photos and made phone calls, the cat eventually stopped talking to us. I think he gave up on us. A few minutes later, he decided to change positions. I think his legs were getting tired of holding him up. After all, we had no idea how long he had been up there; a good samaritan had phoned about him about an hour previously, but the road we were standing on was small and rarely used, so he could have been there unnoticed for hours. I also think he was trying to assess his situation, see if he could take matters into his own hands and find his own way down, since we were clearly useless.

As he moved around on the little tree, it bent terrifyingly. Unable to help ourselves, the rescue driver and I yelled “No, stay still!” up at the cat. This had about as much effect as you’d expect. But he managed not to fall. Over the next thirty minutes, waiting for help to arrive, we watched as he periodically moved around and tried to find a way down. We became worried enough about him that the driver put on her dry-suit and made her way down to the water so that she could fish him out if he fell.

Finally, as the light was failing, our help arrived, in the form of the driver’s boss who had driven down from Boston. Now things started to move quickly. As the cat watched with trepidation, the driver got into the water (in her dry-suit) with a big net; I hovered with another big net; and the driver’s boss attached ropes to the little tree. He pulled, and the tree bent towards the roadway where we stood. The cat braced himself, then, when he was only about ten feet off the ground, jumped. I swung with the net and missed. We watched as the cat ran at top speed away from us down the long road and disappeared into the night.

Links post

2011-11-19T20:57:00.001-05:00

I haven’t been reading many blogs lately, so these link recommendations are pretty old. Still delicious, though.

Who’s your double merle daddy? (Border Wars): The devil’s bargain of breeding a collie who is guaranteed to produce blue merle colored puppies.
Shelters: Pit bull drop-offs on rise (Telegram.com): My local newspaper reports that since Worcester, MA passed its anti-pit bull ordinance, pit bull drop-offs at the area shelter have increased.
It works! How to stop an approaching dog in an emergency (The Other End of the Leash): Patricia McConnell’s excellent advice about what to do when a dog is running at you, and your dog isn’t going to react well. Comes with video, so it is extra yummy.
Patricia McConnell Seminar: What Science Tells Us About Puppy Development (Reactive Champion): A summary of a Patricia McConnell seminar on, oh wait, you can read the title.
Breeding Discontent (Paula Kislak, DVM on the HSVMA website): More on the pitfalls of irresponsible dog breeding practices. “All stakeholders [in dogs] ... should forge cooperative alliances and develop robust plans to improve canine health and welfare”

How to spay a cat fast

2011-11-10T06:33:00.000-05:00

Yesterday I spent the day on a spay/neuter trailer. The shelter which owns the trailer sends it out to low-income areas to spay and neuter a large number of cats and dogs at low cost. Yesterday was a slow day; we spayed and neutered sixteen cats. Well, the vet spayed seven and neutered three; I spayed one and neutered three. Meanwhile, she explained high volume spay/neuter techniques to me.

The key to high volume spay/neuter is, obviously, speed. She can spay a cat in seven minutes. It takes me about thirty; a general practitioner who has more experience than I do, but isn’t as obsessed with speed, might take ten or twelve. This is what I learned:

Keep your surgical field (the animal!) clear. Take the time to replace your instruments on your instrument tray when you are not using them, so that you have less visual clutter.
Always know where each surgical instrument belongs. Don’t leave them in a pile or even a random row on your tray. Have an order for them — any order, so long as you are familiar with it and can reach for a particular instrument and know right where it will be.
Don’t waste movements. If you’re reaching to the right to grab a new instrument, don’t twist all the way over to face the tray; just reach your right hand over.
Don’t get tangled up in your instruments. Be willing to take a second to switch hands if you have yourself in an awkward position.
As you’re working on one step, have your next step in your mind. What instrument will you be reaching for next?
Relax. Stand up straight. Breathe, breathe, breathe.

Working with Sadie

2011-11-04T06:01:00.000-04:00

Sadie was a rambunctious young shelter dog whom I had been assigned to exercise and train. We were working in an auditorium, the best space the shelter had for exercising dogs indoors. Like most of the dogs I worked with in there, Sadie had some trouble with the smooth floors; every time she ran to catch a ball she would slide and slam into the wall. Because she was basically an oversized puppy, this didn’t faze her. We were having a great time, working on her retrieving skills, practicing “drop it” (at that point, just a swap of the ball for some treats).

Then Sadie saw some dogs playing outside through the big glass doors on one side of the auditorium. Sadie was already diagnosed as dog aggressive, which was part of why she was inside playing alone with me. The mood of the session changed immediately. Sadie ran at the glass doors, barking and racing back and forth. I tried to interpose my body between her and the doors, to back her up and get her attention back on me, but it was like I wasn’t there. I wanted to put her leash on to back her away, but I was worried that grabbing her collar would cause her to turn and bite me.

I made Sadie’s leash into a loop and lassoed her with it, then backed her away from the glass doors. She still wasn’t focusing on me, but neither was she turning to bite me as we backed to the far end of the room, where I sat down on a low stage and kept her on leash. She had her back to me, focusing on the doors. She couldn’t see the dogs any more, but she could hear their deep hound barks, and she really wanted to get at them.

Sadie had worked with a clicker already, so I pulled out my clicker and started to click her for any movement away from the door. Step back towards me: click, handful of treats. Quick look over her shoulder when I made kissing noises at her: click, handful of treats. I kept up a very high rate of reinforcement to keep her interest, so she was essentially being fed a steady stream of pieces of hot dog. Gradually her body language changed, so that she was not arrow-straight pointing at the door. She became looser, more relaxed. She turned towards me, looked at me (treat, treat, treat). And then finally she was lying down next to me, leaning into me, enjoying having her sides rubbed. When the dogs barked, she looked over towards the doors briefly, then back at me. She was with me again.

Being a food animal veterinarian, day 8

2011-09-30T13:38:00.000-04:00

Day 8 was not like the other days. My rotation-mate Delilah and I signed up to spend the day assisting with embryo collection at a farm that works with my school to preserve heritage breeds. The farm acquires (usually on loan) individuals from heritage breeds of sheep, cows, and goats. They superovulate and breed the females, then collect the embryos and cryogenically store them. Del and I kept asking what the plans were for the embryos. No plans! We are just storing them in case they are needed some day when these breeds are extinct.

The facility was beyond lovely, a 1920s folly farm that looked like a crazy cross between a medieval castle and a Mexican mansion. Biosecurity was a big concern there, so we had to cross a little bridge with a foot wash on the way in, and multiple signs about the premises said things like “This is private property. Please go away immediately.” The grounds were so immaculately clean that it was hard to believe there were animals there, but there were, beautifully cared for (with lots of pasture!). The farm was restored and updated, so you would for example pass through a stone archway into a modern cryogenic storage facility. Also, it had the cleanest bathroom I had encountered on a farm yet, but then again, that is not saying much. Most farms have bathrooms that rival the worst truckstop bathrooms, so that the vets who drive the trucks will say things like “hang on, we’re passing by a gas station in less than an hour” when you ask about facilities.

Del and I traded off assisting on surgeries and running anesthesia for three ewes. We premedicated, intubated, and maintained each ewe under anesthesia on gas. Then we helped Dr. Thery go in laparoscopically to make sure she had in fact successfully been superovulated. Ideally the ovary would look like a bunch of grapes. We would count the post-ovulatory structures on each ovary. Then we would laparasopically find and grasp the uterus, and pull it out of a small incision. Once it was exteriorized, we flushed it to get all the embryos out of it. The embryos were carried over to the lab, and we watched on video as they were identified, counted, and graded (the more vs less viable ones selected out). We closed up the ewes and recovered them. Each ewe would be kept for two surgeries, then returned to her owner.

It was a lovely day, and of course the surgery experience was a fun bonus. Del and I had some interesting conversations about whether this effort to preserve heritage breeds was worth the investment. Whether or not it is, it was a beautiful facility, and nice to see how a farm can be run when money is essentially not a factor.

Being a food animal veterinarian, day 7

2011-09-25T14:24:00.000-04:00

Day 7. Just me and Dr. Gray (my favorite doctor to ride with). He blasted out of the clinic at high speed, announcing that we were extremely late and that we were going to check on a herd which had a problem with cystic ovaries. He tossed me a copy of Merck’s Veterinary Manual and said, “Let’s get smart about cystic ovaries.”

He and I at least knew what cystic ovaries are, but I am betting you do not. What you want an ovary to do is to grow a bunch of follicles, and then have one follicle decide it is the queen follicle and ovulate an egg. You probably know what happens from there. If this process is stymied at some point so that the follicle just hangs out and doesn’t develop, but becomes a bump on the ovary full of liquid, it is a cyst. The cow may recover from this and return to a normal reproductive cycle, or her system may become confused by the particular mix of hormones circulating and get hung up. The a veterinarian has to figure out what is going on. The most common explanation is that the cows are not eating well enough, so we came prepared to look into that.

We pulled up at a lovely little farm. This was a hobby farm in the sense that the owner had income from elsewhere, but a real farm in the sense that he was trying to make a profit on selling milk. He actually had a farm store where you could buy milk from that farm (unheard of!) and ice cream made from the milk (even better!). I purchased both, since the cows were out on grass, which made me happy. (The milk later spilled in Dr. Gray’s truck and went bad so that he became cranky with me, but that is a different story.)

Herd check. Why did the cows have cysts? The usual veterinarian for the herd was present; we had been called out as consultants basically because we had an ultrasound machine to help us better see what was going on inside the cows. We checked cow after cow. Some follicles (excellent), some post ovulation structures (also excellent). No cysts. It turned out that what had appeared to be cysts were actually normal structures. The cows were in fact somewhat skinny, so we also did some education about how to body condition score a cow. This was a learning experience for me; it is more complicated than with a dog, involving a flow chart. We also gave advice about how to synchronize the cows so that the farmer would know when to breed them. Without a solid synchronization program (or a bull, which most people find dangerous to keep around), you just have to watch the cows to see when they might be in heat. They are in heat for such a short period of time, less than a day, that it is very easy to miss. Best to know ahead of time when it’s going to happen.

We got back in the truck. I ate my ice cream sandwich for lunch. It was a good lunch.

The next farm was very different. Instead of the welcoming committee of three people who had received us at the first farm, we were left to find the sick cows on our own. Eventually one of the employees handed us a list of numbers: three cows with possible twisted stomachs (displaced abomasums) and one that might have a dead calf inside her. Usually farmers catch the cows up for us and have them in headlocks, but not here. Go find them!

The sick pen had dozens of cows in it. Dr. Gray and I wandered through until we found our girls, then chased them into a small side area where we could put them into the single head lock one by one. The cow with the presumed dead calf was pretty sick, so Dr. Gray dealt with her while I checked TPRs (temperature, pulse, respiration) and gave physical exams to the other three. I couldn’t see him, as he was behind a barrier from me, so I was on my own.

First cow: already in the head lock thanks to Dr. Gray. Normal TPR. No pings (the sound they make when you thwack your finger against their belly and they have a twisted something or other inside there). Looked bright and alert and not dehydrated. I relayed this to Dr. Gray, he came over and double checked, said we would just recommend some oral fluids, and I should move on to the next cow.

Second cow: obviously not in the head lock. I released the first cow and tried to get the second cow in. They will move away from you, so you can basically chase them into where you want, but she would not actually put her head in the lock. They weigh a lot more than you; sometimes you can shove on the back end and they will be nice about it, but there was no way this girl was cutting me a break. It was a little embarrassing, but I did my TPR while she was loose.

This time Dr. Gray came back with blood on his arm up to his shoulder, looking stressed. He checked over the cow (who he also failed to get into the head lock), gave her a rectal exam (this was all with a bare arm — iew), gave her the same diagnosis as the first cow, and went back to what he was doing. I walked back to watch as he shot the sick cow with the dead calf inside her in the head with a captive bolt gun, standard euthanasia technique on farm for a cow who cannot make it on to a truck to be shipped to slaughter.

Dr. Gray explained that the cow had had a dead calf in her for several days, and had a large rip in her uterus, which she could not recover from. I will save you from some of the gorier details. He was clearly somewhat bothered by the fact that the calf had died at least four days before and she had not gotten medical attention before then. “To be fair,” he said, “the calf wasn’t in the birth canal so she probably didn’t show any signs of labor for them to notice.” I said, “Is this maybe a case where on a smaller farm, someone would have realized something was going on with the cow which was supposed to have freshened a few days ago?” He allowed as to how that was probably the case.

Then we checked out the fourth cow, the one which was also supposed to have a displaced abomasum. Amusingly, this cow stuck her head into the head lock enthusiastically. We were running late, so Dr. Gray did this exam himself, and did find a problem. He is a fan of a toggle procedure to fix displaced abomasums, so that is what we did, instead of the surgical procedure I had seen previously. With the help of a farm hand, we sedated the cow, put ropes around her, pulled her over on her side, and rolled her on to her back. Once she was on her back, her stomach floated into the correct place. Dr. Gray put two pins into her belly, puncturing through the skin and into the stomach. He used the pins to secure the stomach in place. The cow was allowed to stand up and was good to go (with dextrose, steroids, oral fluids, oral calcium, and B vitamins to help her out).

Then we washed off in a bucket. There was a lot of scrubbing to be done. And that was day seven.

Olympic level dog training seminar

2011-09-25T09:24:00.000-04:00

The nice thing about having weekends free on your ambulatory rotation is that you can do the things normal people do with their weekends, like go to incredibly geeky dog training seminars about the details of learning theory. I went to a seminar on improving the cues you give your dog with the brilliant Kathy Sdao. Some of her main points, below.

A command is something you give with the expectation of making the animal obey. A cue is something you give to say “you know that behavior that you have learned is a really good thing to do, because you often get paid to do it? Now would be a great time to do it!”
Oh, for those of you who aren’t dog training geeks, I should back up. “Getting paid” is dog training lingo for the idea that dogs don’t work for us just because they love us. Do you do work because you love your boss? Dogs get paid with food, praise, life rewards (getting a ball thrown), etc.
You can’t control a behavior. You can only control what happens before and after a behavior, and therefore the animal’s expectation for cues that predict a good or bad time to perform the behavior, and consequences of the behavior.
You certainly can use cues which are difficult for your dog to distinguish, like down and out, which have the same internal vowel sounds and are very similar to the ear if you don’t have human-level language skills. However, why would you? Choose words that make things easy for your dog by being easy to distinguish from each other. Your dog is the one who is struggling to understand language, something his species does not excel at.
We know it, but it’s worth repeating: a dog doesn’t refuse to perform a behavior for spite. That’s only something humans do. A dog who doesn’t respond to a command or cue does so for only one of two reasons: a) he doesn’t understand what is being asked of him, or b) he doesn’t feel it is worth his while (he is not being paid sufficiently).
We think of cues as verbal or gestural. Of course, dogs are more comfortable with gestural cues in general. (One participant found that her dog completely ignored a verbal cue which she had always given paired with a gesture.) You don’t have to make gestures only with your hands! Some people with small dogs find that the dogs respond very well to foot gestures, which are closer to their eye level.
Cues that we give without meaning to include eye movements, where our attention is, body language (the classic story of the dog refusing to lie down unless the owner bends forward, because that may not be the cue the owner taught, but it is the cue the dog learned). Tone of voice. Time of day. Antecedents like picking up your keys. My dogs have learned that “okay,” spoken while I am on the computer, means I have decided to get up and get myself off the keyboard, even though it is something I say unconsciously to myself and not intentionally to them.
Dogs live in a sea of information coming from us. Sometimes it is hard for them to pick out the cue we want to give. You think you are just raising your hand to indicate sit, but the dog is taking in tone of voice, where you are looking, if you are bending forward, what your other hand is doing, the position of your feet. It isn’t obvious to the dog that the hand (or word) is what he is supposed to be paying attention to.
Kathy gave two examples to illustrate that point. The first: you know the feeling you get when you are tuning a radio and you can’t quite get the station, and have to listen to it through static? Dogs live in that world all the time.
For those who know the invisible gorilla illusion — if you don’t know to look for something, you may not see it. If the dog is paying attention to how far forward you are leaning, he may not even hear the word you are saying to him. After all, words come out of your mouth all the time, and he usually doesn’t understand them. Why should he pay attention to this one and assume it has some importance? Why should his brain even filter is so that he hears it at all?

We played a fun game with the participating dogs called “Prove It.” The handler asserts something like “my cue for sit is the word ‘sit.’“ The challenger says, “Yeah? What if you say it with your eyes closed? With your hand over your mouth? Looking at the ceiling? Whispering? Standing on a chair? Will your dog still do it then?” I worked with a handler whose dog did standard commands flawlessly, promptly, and enthusiastically. When her handler told her to sit while looking at the ceiling, the dog stared at her hopefully, trying to figure out what she was supposed to do. (During this game, we took lots of breaks to give the dogs easy tasks and reward them.)

Fun day learning about how to communicate with your dog, and gave me good insights into my own training methods. Kathy Sdao is an excellent teacher. If you are a beginning trainer, her classes may seem a little arcane to you, but I highly recommend her if you are a learning theory geek, or someone who teaches other people to train dogs.

Being a food animal veterinarian, day 6

2011-09-19T21:34:00.001-04:00

Day 6. Another herd check. It’s becoming routine. To be fair, I tend to end up riding with the clinicians who do herd checks, because I want to spend these three weeks working with cows. I have so far avoided riding with the clinician who specializes in horses, because equine medicine bores me silly. I like horses, just not horse medicine. And I really like cows, who are endlessly sweet and amusing, and I like herd health, or population medicine. Put me on a farm with a few sick cows and I am perfectly happy to spend hours talking about what is wrong with farm management which is causing these cows to get sick. Ask me to actually do procedures on an individual cow and I start wondering when we are moving on to the next farm.

So. Day 6, herd check. After all the rectal palpations there is inevitably the one or two sick cows to check on, or in this case, three. One was six weeks fresh (gave birth six weeks ago). You always, always ask how fresh a cow is, or if she is not particularly fresh, how many days in milk (how long she has been giving milk, i.e., how many days ago she gave birth — I have been told things like “this cow is 510 days in milk”). They get different diseases depending on where they are in the whole calf-milk-breeding-no milk-calf cycle. This one, being six weeks fresh, should have been past any problems with her uterus recovering from labor, but was not. Which was why we were being asked to look at her. We recommended infusing her uterus with dilute iodine to get rid of the infection.

The next cow had aborted two days previously. She still had bits of placenta hanging out. Normally retained placentas clear themselves within a day or two, but this one was hanging in there a little long, especially for having quite so many pieces still stuck in. My syllabus says it is “controversial” to “manually clean” the uterus of retained placenta (i.e., go in and pull the bits out by hand). It is usually better to let nature take care of this, as upsetting as it is to see cows walking around with pink stuff dangling out of their private parts (what small animal owners inevitably refer to as “down there” and what farmers will refreshingly refer to as “vaginas”). In this case, we manually cleaned. Well, the vet cleaned, and I watched. Good times.

Sick cow #3 had some hair loss on her heels and at the head of her tail. The clinician took one look and pronounced her as having mange. We applied a parasiticide: the vet handed me a big bottle and told me to pour it along the cow’s top line. The stuff was bright purple. Now the cow was bright purple. More fun than cleaning placentas.

Farm two. A big farm, but a well run one. They were having a diarrhea problem with many of their calves (“calf scours”). We drew blood on some four day old calves to check to see if they had gotten enough antibodies from their dams in the colostrum (milk full of antibodies) that they drank in their first few hours of life. (Back at the clinic, the answer was that two of them were fine, and two of them were borderline for not having enough antibodies.) This was a great example of a herd health problem. Why were these calves getting sick? It seemed to be some management problem, but where exactly was the farm going wrong? If the calves weren’t getting enough colostrum, why not? The guy in charge of calf management spent a long time talking to the vet to try to figure it out. So far, we still have no answer. I hope they manage to find one.

Being a food animal veterinarian, day 5

2011-09-17T05:54:00.000-04:00

Day 5. I was refreshed after a weekend of sleeping 13 hours a night (still catching up after my exhausting small animal surgery rotation the previous month). I signed up to ride with Dr. Gray and my classmates Will and Anna.

Farm one. A largish farm for a family farm, but run by people who clearly really cared about their cows, a mom and daughter team. Anna performed a castration; Dr. Gray said I could show her how since I had done one before (making me an expert, clearly). There was a long discussion about whether to use lidocaine (a painkiller) or not, as there always is when calf castration is discussed. Since this is something I’ve thought about a lot, I was able to present the usual pro and con arguments to my rotation mates. We used lidocaine. The calf was a lot bigger than the one I had done before. My advice: do them younger. The restraint is a lot easier.

Then we did the usual herd check. One cow had had a forced extraction recently, a difficult birth ending in having the baby pulled out of her using chains. Dr. Gray did a vaginal exam, which is more uncomfortable for the cow than a rectal exam, such that students are not allowed to follow after and do their own exam. She had multiple internal lacerations, so Dr. Gray recommended antibiotics and pain killers. This was one of those sticky situations where pain killers weren’t absolutely necessary, just indicated for the cow’s comfort. He thought the farmer wouldn’t want to give them and considered not even suggesting them, but in the end did suggest them (“if you wanted to give some banamine, it wouldn’t be wrong”) and the farmer promptly agreed. I had thought she would, since she seemed to really care about her cows. Veterinarians, it is not wrong to just suggest the best care, even if you think your client will say no! You just have to find a way to do it in a way that won’t make your client feel uncomfortable if they do feel they can’t afford it.

Overall, I mostly liked how these cows were kept; the health of the cows was clearly a high priority on this farm. I am still not happy that the industry standard keeps cows on slippery concrete where they are bound to develop foot problems (10% of a herd is expected to be lame on any given day), walking in manure so that they are caked with it up their legs, and not getting to eat the grass that they evolved to eat.

Second farm of the day: we preg checked (pregnancy checked, rectally) about 100 cows. PHEW. Luckily there were three of us. As the herd check started winding to a close, Dr. Gray put Will and me on the task of giving the cows the injections that they needed. When a cow was preg checked and found to be open (not pregnant), with structures on her ovary to indicate that she had recently ovulated, she got an L written on her side in orange chalk. When she was pregnant she got a P. Otherwise she got nothing. I injected all the P cows with a multiple vaccine. Early pregnancy is a good time to vaccinate so that the mom will pass on the antibodies to the baby in her colostrum after birth. Will injected the L cows with Lutalyse. This is a hormone (prostaglandin F 2α) which causes them to reset their estrual cycle so that they will ovulate in the next three days and can be bred again. In general the female vet students avoid handling Lutalyse, because if it gets in our system we get very bad cramps. I was glad to have Will there to give those injections.

Being a food animal veterinarian, day 4

2011-09-12T20:58:00.000-04:00

Day 4. Friday! I was hugely looking forward to having an actual weekend off, with no responsibilities in the hospital for the first time in 5 weeks.

I was one of the first students in to the clinic. Dr. Cole caught me and my classmate Will as I was coming in and told us that a client had just pulled in. She was bringing her extremely elderly and sick dog in to the clinic for euthanasia. The clinic technically doesn’t handle small animals at all, but Dr. Cole was willing to help out the client in this case. We euthanized the dog in the back of the truck, lying comfortably on his blanket. Will and Dr. Cole handled the actual euthanasia, while I talked to the owner about her dog, what he was like.

I rode with Dr. Thery that day. We went out to a small farm which produces artisanal raw cheese for sale in New York city and directly to restaurants in the area. I loved this farm. The cows were all out on grass all summer. The barn was old but very well maintained, not overly dirty. The cows were extremely friendly; even the calves were not head shy at all. We did a herd check, popped an abscess on a cow’s flank, and vaccinated and TB tested a mess of heifers (about to be sold across state lines) and calves.

I kept ducking out of doing the actual medicine to go talk to the farmer about how she makes grass feeding work. Grass feeding is the norm for beef cattle before they go into feedlots, but for dairy cows, conventional wisdom is that they have to be handled too much to make it work. What a pain to have to round up all your cows twice a day for milking! But the farmer shrugged that off. The cows want to be milked, because their udders get uncomfortably full. They come back in to the barn voluntarily. Once they know the routine, it’s no problem.

I wish all farms could be like this one. I know that’s a pipe dream, but I still really want to find a way to support farms like this one, to make it just a little easier for farmers to do what I consider to be the right thing by their animals.

Surgery rotation vs ambulatory rotation

2011-09-11T16:13:00.000-04:00

Surgery: Get yelled at if you hold your hands below your waist, even for half a second, while you are sterile
Ambulatory: Perform surgeries on manure-encrusted surfaces

Surgery: Why would people who are in the operating room just to observe want chairs?
Ambulatory: Spend 1/3 of your day sitting in a comfy truck seat

Surgery: Discover that it rained when you see wet ground upon leaving for the day
Ambulatory: Discover that it is raining when you have to change into your coveralls standing under the open sky

Surgery: Your patients have names like “Sweetie-Boo”
Ambulatory: Most of your patients are addressed as “Boss” or “Girl,” except for one who acquires the name “The Cow We Had to Take to the Vet Clinic”

Surgery: Special room to scrub in, covered in signs with complicated procedures for doing so
Ambulatory: Scrub in using soapy water in a bucket

Surgery: Dress is business casual
Ambulatory: I consider most of my t-shirts too nice to wear (you have to be prepared to get poop on everything)

Surgery: You think your patient has developed feline idiopathic cystitis? Don’t worry about it. We don’t do internal medicine, just surgery
Ambulatory: We do internal medicine, surgery, theriogenology (reproductive medicine), dermatology, cardiology, neurology, ophthalmology, population medicine, public health

Being a food animal veterinarian, day 3

2011-09-10T13:12:00.000-04:00

Day 3. I signed up to ride with Dr. Cripi, just him and me. I was hopeful that I would get to do more hands on stuff when I was not competing with other students for opportunities.

I expected to get right in the truck and head out, but Dr. Cripi said that a cow was being brought to us this morning. Some farms are so far outside the clinic’s usual area that they are only worth visiting if there is some other work in the same region. These farms can be our clients, but have to let us schedule our visits to groups of them on the same day. When they have emergencies, they have to bring their animals to us. This was why the cow was coming to us now.

She got off the truck nicely and we put her in the stocks so that she was restrained and could easily be examined. Dr. Cripi noted that her eyes were sunken, indicating dehydration. Some other students were standing around as well, and we all got to examine her. A large part of examining a cow is trying to identify problems with its complicated GI system. If part of the GI is displaced to somewhere it shouldn’t be (a fairly common problem, especially in cows that are fed too little roughage in their diets, e.g., are not out on pasture or fed mostly hay) then that part of the GI will start filling up with gas. You can “ping” the cow to hear this. You snap a finger hard against her side while listening with your stethoscope. This was the first ping I had ever heard, as I had never before examined a cow with a displacement. It sounded like a basketball bouncing on a metal floor. I referred to the ping as “gorgeous,” which amused the farmer no end.

This cow had an RDA, or right displaced abomasum. This means that the cow’s true stomach, or abomasum, had floated up on the right side of the cow. (Normal location: right side, but a lot more ventral, e.g., closer to the ground). We performed standing surgery on the cow to fix the problem. We did not sedate her, as she was so sick that Dr. Cripi thought sedation would make her lie down, which would make the surgery much more difficult. We did give her a local block in the area where we would be cutting. Then she was shaved and prepped (aseptically scrubbed) over her right side.

First we scrubbed in. This was hilariously different from scrubbing in to surgery in the small animal hospital, which I had done a lot of on my surgery rotation over the previous month. A cow holding area is going to be inherently dirty. We scrubbed our arms off with iodine and put on long surgical gloves (they have to go up to your shoulder, because you’re going to be reaching deep inside a big animal), then normal sterile gloves on top of that.

Then Dr. Cripi made a maybe 5 inch incision in the cow’s side. She didn’t seem to notice; hurray for local anesthetics. He pointed: “See? Her abomasum is right there. That’s huge!” The abomasum was hugely distended with gas and floating right under the surgical incision. Dr. Cripi put a needle into it, attached to a long tube, and let a lot of the gas out. He had all the students smell the gas: a sort of sweet smell, much nicer than rumen smell. (The rumen is the largest and possibly most important part of the cow’s complicated four chamber stomach, the part that feed first falls into to ferment.) The farmer declined to take a sniff, and made a face.

Once the abomasum was somewhat deflated, Dr. Cripi tacked it to the body wall with tacking sutures. Then he closed the incision’s lower layers with the biggest needle I have ever seen in my life. Then he showed me how to close the last layer, the skin. I have done my share of small animal skin closures, and this was really different: that cow’s skin was insanely thick and tough. If you’ve sewn leather, you know what it’s like. I had to really put my back into it to get the needle through.

Then we dosed the cow with a liter of intravenous fluids plus dextrose, and a liter of electrolyte solution. I got to hold the fluids up “as high as you can!” If it is going to make your arm tired, it is the student’s job.

Then the cow walked politely back on her truck and went home.

We got in our truck and headed off to our first farm, with Dr. Cripi angsting about how late we were the whole way. En route, we talked about our lives. Some ambulatory vets use the ride as a teaching opportunity (Dr. Mulain); some ride in silence (Dr. Thery); some just want to chat (Drs. Cole and Cripi). Dr. Cripi had a pretty interesting life, it turned out, spending five years just traveling the world before realizing he wanted to work with food animals as a veterinarian.

Farm number one: a herd check. Checking cows in a herd for pregnancy seems to be the bread and butter of the practice. It was a typical concrete floor, feces-covered barn, but with a particularly open design that I really liked, basically just a roof over the cows, no walls. I asked about their plans for winter (this was a brand new structure). They intend to put up some cover then, but nothing permanent. We worked with a fantastic view of rolling Connecticut hills. It was a lovely scene to look at while putting one’s arm up a cow’s butt.

This farm’s staff included a scrawny kid just out of his teenage years who noticed that a female had arrived and immediately took off his shirt. This became even more hilarious when I was told that it was my job to castrate a bull calf and that the kid would help restrain. I later asked Dr. Cripi if the kid took off his shirt every time a female vet student appeared. Dr. Cripi rolled his eyes and said yes.

How to castrate a bull calf: the vet will draw a diagram for you on a paper towel, hand you a scalpel, and send you on your way. I asked if we used lidocaine for analgesia; he said I could if I wanted to. I said yes please. (The debate in use of lidocaine for a local block in castration is that arguably it is more unpleasant to have a needle shoved into multiple spots in your scrotum and have something that burns injected than just to have the stuff ripped off real quick. Personally I think pain meds are mandatory, but even more so if the job is being done by someone who’s never done it before.) I gave the calf lidocaine injections at various locations around his scrotum and waited five minutes for it to take effect.

My experience in castrating dogs and cats was helpful. I cut off the tip of the scrotum, squeezed the testicles out. They are slippery and don’t like to come out, but I had done this before on a smaller scale and knew how to squeeze. Then I grabbed them and pulled until they came off. (The hardest part was getting a grip. In small animal medicine one uses little four by four pads to hold on to them, not your hands.) The kid asked why we didn’t just cut them off. I said that Dr. Cripi hadn’t said, but my guess was that the bleeding would be worse if you cut; ripping provides some hemostasis.

Farm number two. En route, the sun came out. My spirits immediately lifted. It is amazing what a difference some blue sky makes. At this farm we had a sick cow who was two weeks fresh. This means she gave birth two weeks ago and has been being milked for two weeks. The stress of parturition means that many of these fresh cows are at risk for a variety of diseases, like a displaced abomasum such as we’d seen earlier that morning. In this case, she seemed to have some nerve injury from when the baby passed over the obturator nerve along the pelvis. We prescribed rest, TLC, and anti-inflammatories (banamine is what you give to cows).

Farm number three. Another hobby farm, but a somewhat bigger one. This farmer had quit her previous job to just be a cow farmer, and her husband’s income was presumably supporting the operation. The cows were out on grass in a truly lovely setting (we drove over a little covered bridge across what I have to describe as a sparkling brook on the way in). The cows were spotlessly clean. Normally you sort of hesitate to pet them because of all the manure all over them (at least until you have manure on your hands, which inevitably happens). These cows were so clean that I actually sniffed one and discovered that natural (manure free) cow smell is a lot like horse smell. The farmer had put the sick cow into a holding area, which had a concrete floor which was also spotlessly clean. No huge masses of spider webs! No dead birds in the rafters! Crazy! The farmer actually hovered with a bucket to catch the urine when the cows peed, which is farther than I would go in her place, but I really did appreciate the cleanliness. As Dr. Cripi pointed out, these cows were basically pets.

This cow had a left displaced abomasum (same problem as the first patient of the day, different side). LDAs are actually a lot more common than RDAs, which is too bad, as you still have to cut on the right side of the cow (the rumen covers everything on the left side) and as you then have to reach across the inside of the cow to get to the abomasum on the other side, it becomes quite a process. This cow was dry (no longer being milked) and due to freshen (give birth) in a few weeks. Dr. Cripi was amazed that she had an LDA. Dry cows almost never get displaced abomasums; it is a disease of fresh cows. Cows out on grass also almost never get this disease. This particular cow also turned out to have pneumonia, so maybe the stress of that had caused the displacement. Weird.

So, same surgery, except that Dr. Cripi had to reach through the cow this time instead of having the abomasum pop right up under his incision. I did not get to close, as I had inadvertently contaminated myself on the cow’s side while trying to prevent the drape from falling off of her.

Last farm of the day: again, a horse owner. Her horse needed his yearly vaccines. He was 31 years old! He was a super nice horse. Dr. Cripi sat down and handed me the vaccine bottles. I drew them up and injected them into the horse’s neck. He never flinched. Old patients can be the easiest ones to handle.

End of day 3: less wet, more confident, starting to have fun.

Being a food animal veterinarian, day 2

2011-09-09T20:08:00.000-04:00

Day 2 of my Ambulatory rotation. Still raining. I rode with Dr. Cole and one other student.

First we visited a lovely hobby farm, meaning a farm which is not expected to bring in enough revenue to support the owner. These owners bred and showed registered Ayershire cows, and sold their milk as a sideline. They had full time jobs elsewhere. This was a tiny barn, milking around just 20 cows, very clean relative to other barns (I never had to wade through an ankle-deep sea of manure, which is more than I can say for some other farms we visited), and the cows seemed very healthy.

Next we did a herd check at another, larger farm. More rectal palpations. I complained to Dr. Cole that I had no idea what I was doing when I put my arm in there. He walked us through a guide of how we should approach the situation, complete with an actual size model of a cow uterus. Awesome! Here are his instructions, because I know you are desperate to know:

First you feel for the vaginal canal and/or the cervix. These are fairly caudal (the direction of the cow away from the head) so don’t overshoot them.
Follow the cervix cranially (forward). Behold the body of the uterus.
The body of the uterus may have fallen off the floor of the pelvis into the abdomen. If so, grab it and pull it back up onto the pelvis so you can handle it.
Follow the uterus to the right. Ovary! Not necessarily round. It may be more elongated. Often golf ball sized.
Do the same on the left.

I got to where I could find the vaginal canal and/or cervix and the uterine body pretty reliably. I am still bad at finding the actual uterine horns. If I hunt around long enough I can blunder into the right ovary, but it is awkward to reach to the left, so I have yet to find the left ovary. (You palpate with your non-dominant hand so that your dominant hand is free to do things like write down your findings. So I palpate with my left hand. Since you face towards the cow while you’re palpating, reaching to the right is easy and reaching to the left is hard.)

Next stop was another farm for a herd check, 2 rabies vaccines, and 2 health certificates for some calves that were being taken to the fair. We’ve actually done a fair number of health certificates this week. Autumn is town and county fair season, so the kids are all taking their cows out to show them. At this farm I got to see one cow being prepped for the trip by being buzzed down smooth with some clippers.

The last farm was a herd check, 3 calves to dehorn, and 3 lame cows to check on. We tied each lame cow to a post by the head, then lifted the problem foot by means of a complicated rope pulley system that I supposedly learned in my Clinical Skills class but which I certainly could not duplicate on my own. (“Throw a half-hitch here... That’s not a half hitch! Well, do you at least remember how to do a quick release knot?”) The cows would then kick and freak out, so someone had to tail jack them to keep them distracted. Tail jacking means holding the cow’s tail straight up. To do this you have to stand very close to the cow and lean into the tail. She won’t kick you once you’re close, because they kick out to the side, not back. But getting close can be tricky. I learned: get in and tail jack her before they lift her leg and she starts hopping around and kicking. That works much better. (Trim feet down so you can see the problem. Declare the problem to be hairy heel warts. Yes, that’s an actual disease, caused by a species of bacteria. Apply powder antibiotic and bandage the foot. Done.)

Day 2 done. Still cold. Still wet. Starting to feel more like I know what I’m doing.

Being a food animal veterinarian, day 1

2011-09-08T21:09:00.000-04:00

The first day of my ambulatory (food animal medicine) rotation, I got horribly lost on the way to the clinic, which is about an hour from my home. I came in late and missed half of the orientation. Ambulatory is so called because its vets go to the clients rather than vice versa. There are eight students on the rotation right now, but we break up into groups of one to three and ride along with individual vets.

Day one, three students, Dr. Mulain.

Farm one: herd check! Lots of rectal palpations to discover the pregnancy status of cows. If not pregnant, they would get an injection of a medication to reboot their reproductive cycle, so that their owner would know when they were going to come back into heat and therefore when to breed them. Dr. Mulain palpated first and we followed after, one student per cow. Mostly I put my arm in and waved it around aimlessly, hoping to randomly encounter a uterus.

We also dehorned some baby calves at this farm, and checked up on a lame cow who had had a claw (half her foot) removed a few weeks ago. Her bandage was removed and the clients were told to clean her foot regularly. We checked another lame cow, trimmed back her foot, and cleaned out a sore on it.

Farm two: a steer had been hit by a car! The barn had been broken into by thieves the night before and the inhabitants had escaped. The steer was covered in road rash, which we cleaned. His tail was mangled, and we amputated it. His biggest problem was a dislocated hip. We provided anti-inflammatories and advice that he was unlikely to be able to live with a dislocated hip, but that there was a small chance it would heal.

This farm also produced a calf who had injured her eye a few days before. The eye was not salvageable. We put the calf under general anesthesia with an injection and laid her down on the barn floor, then removed the eye. It was an odd experience for me, as I had just finished my small animal surgery rotation. The levels of cleanliness vary tremendously between the two rotations, to say the least.

Farm three: a house with two elderly horses in a tiny barn out back. One had been suffering from neurologic disease for years and was now increasingly lame. We cleaned out an abscess on his hoof and put on medication and a bandage. The horse looked like he was minutes from expiring, but the vet told us that he always looked like that and always pulls through.

So ended my first day of ambulatory, cold and wet. I trust that the weather will improve, though. September in New England is always lovely.

Things your vet student is good for

2011-08-20T11:19:00.000-04:00

Recently, an owner refused to let me perform a physical examination on his dog. That was for the vet to do. I think he didn’t believe that I had any role in his dog’s care, and thought I was just along to watch and learn from the vets. Not so! (The examples below are all things that have happened to me and owners of my patients.)

At a teaching facility, your vet student is your pet’s primary caretaker. She is the one who knows your pet the best. She has to present your pet’s clinical history to the residents and faculty every day, follow up on test results, and make sure nothing is overlooked or forgotten about. She is also the one who notices things like what kind of food your dog likes best, whether he likes to be taken a little farther from the hospital than usual so that he can pee on grass instead of stones, and takes time out of her day to cuddle with him if he looks sad. (To be fair, the techs also handle a lot of this sort of thing.)
Your vet student is the one who lets you know how your dog is doing. She will call you at least once a day to tell you if your dog is stressed or not, and give you the updates that really matter, like “today he barked at me while I was writing up paperwork until I took him out of his cage to cuddle with him.” Sometimes hearing stories that remind you that your dog still has the same personality as he does at home is just as important emotionally as getting the complicated medical updates from the doctor.
Your vet student is your liaison to the doctor. The doctor is a specialist who is very, very busy. He will give you lots of information, and you will try to digest it all, but you will have trouble really absorbing it. Your vet student is the one who will take the time to answer all your questions in terms you can understand. She will also be understanding if you are anxious about your pet and will tell you that you are going to do fine taking care of him once he comes home. Maybe she will even help you pad the blankets in your car just right before you settle him in to transport him.
Your vet student is required to be a generalist. The faculty and residents on your pet’s case are all specialists. Sometimes having a generalist around is important. If your dog is in for orthopedic surgery, the specialists may be so focused on your dog’s joint problems that they may not think to perform a rectal exam on him, even though he is a ten year old intact male at risk for all sorts of cancer. But your vet student will remember. (The dog had a mass.)

The curse of the missing uteruses, part three

2011-08-07T20:50:00.000-04:00

The first dog I ever tried to spay had no uterus. (She had already been spayed.) And the first cow I ever did a reproductive exam on had no uterus. (She was a freemartin.) That should be enough missing uteruses for one lifetime. But no.

On a recent shelter medicine externship, I was spaying a kitten. On this externship, you get to spay several animals every day, and I had gotten comfortable enough at it that I was hoping to get through the entire surgery without ever asking for help. To understand what I was doing, you have to understand a little about cat uteruses. Human uteruses are one big sac, probably because we tend to have just one or two babies at a time. Cat uteruses are divided into two horns, each with an ovary at the top, and the horn and ovary are attached to the body wall to hold the whole contraption in place. The horns of pregnant cats fill up with kittens, all in a row.The two horns come together at their base, where there is a little uterine body, which connects to the cervix and from there to the vagina and the outside world. To spay a cat, you cut each ovary and horn away from the body wall. Then you have loose horns, and a base which still attaches to the cervix and vagina and outside world. You cut across the base, and then you have a free uterus and a spayed cat.

So I opened this kitten up, careful to make my incision very short. Longer incisions make visualizing your work easier, but obviously are more painful for the animal, and I had just been criticized on my previous spay for making too long an incision. I used my spay hook to fish around in the abdomen, found the first uterine horn and ovary, pulled them out, and cut them away from the body wall. I traced the now-free uterine horn back to the uterine body.

Finding the first horn is hard: you dip in with the spay hook and blindly bring stuff up, mostly intestines, which you have to repeatedly shove back in until you finally get the organ you’re looking for. Finding the second horn is easy: you follow the first one back to the uterine body, and then pull the second horn out where they both split off from the base. Except in this case, I couldn’t find it. I pulled on the uterine body, which should have made the horn pop out, but no go. I pulled harder. The uterine body started to fray. Oops! I didn’t want it to break before I could find the second horn. I had a moment of indecision: I really, really wanted to get through this whole operation without asking a vet for help. And the problem was probably just that I had made the incision too small. But I had seen too many episodes of ER in which overconfident students got into trouble in exactly this way, and if the uterus split apart before I had a chance to put a suture around it to stop any bleeding, that could potentially be dangerous for the kitten. So I called over Dr. Vine.

Dr. Vine assured me that my incision was an excellent size, and pulled on the uterine body some more. It promptly broke off in her hand. (I congratulated myself on setting her up for dealing with that situation instead of getting myself into it.) It was not a big deal, in the end: she hunted down the stump and we put some suture around it. And she said: This cat only has one uterine horn. It only has half a uterus.

Freakish! And cool. And do you know what? Cats that only have one uterine horn always, 100% of the time, have two ovaries. So if you don’t go hunt down that second ovary, they will still have heat cycles. (They won’t get pregnant, of course, but cats in heat are no fun to have around.) Dr. Vine asked me where I thought the ovary might be. I suggested, in my usual precise fashion, “Somewhere sort of near the... kidney?”

It turns out that that was exactly the answer she was looking for, because, even weirder: about 50% of cats who have only one uterine horn also have only one kidney. And this cat was one of them.

In the end, we found the ovary, just sitting there not really near anything, and we removed it. One more missing uterus for my collection, or half of one. These things come in threes, right? Does this experience count as my third missing uterus, or just two and a half?

Land of eyeballs: ophthalmology rotation

2011-08-05T22:09:00.000-04:00

I was really surprised at how interesting I found my ophthalmology rotation. Two weeks of eyeballs should have been mostly boring and creepy, right? But it turned out to be rife with my favorite kind of veterinary ethical issue: how we breed dogs.

Take the several bulldogs we saw who had so many facial wrinkles that their skin was folded over their eyes and rubbed against their eyeballs. (They also had yeast infections in the depths of their wrinkles, but that was a problem for a different department.) These dogs required surgical intervention to cut off the worst of the wrinkles. If they did not receive the surgery, they would be extremely uncomfortable (they all came in with red, squinty eyes), and would eventually get corneal ulcers which would proceed to infections and possible removal of the eye in question.

We also saw a raft of brachycephalic (flat-faced) dogs whose faces were so flattened that their eyes bulged out. Some of them could not completely close their eyelids. Their eyes were at risk for damage just due to being so out there in the world and unprotected. In the opinion of the ophthalmologists, pug owners all need to be given special eye care instructions when they acquire their new dog.

I asked the owner of one of the dogs that required surgery about where he had gotten the dog. He replied that the dog came from a breeder. I suggested that he get in touch with the breeder to let her know about the necessary surgery, so that she could use that information to help her choose wisely which dogs to breed in the future, and try to avoid producing more puppies with the problem. He replied in surprise, “I thought this was just a breed-related problem.”

Yes, these are breed-related problems. But breed-related isn’t synonymous with inevitable. It doesn’t mean we can’t try to avoid them as we create more dogs of that breed. Veterinarians can and should be more clear with their clients about this. They don’t have to be confrontational to do it! They don’t have to imply that the client made a mistake by purchasing the dog. They can instead look to the future: here’s what we can do to make the breed better.

Repost: Learning from Domesticated Foxes

2011-07-31T11:06:00.000-04:00

[This was originally a guest post on The Thoughtful Animal.]

Everyone loves reading about the Siberian fox experiment because domesticated silver foxes are so damn cute. There’s something deeply appealing about the idea of a cuddly fox. And the experiment raised some interesting questions about domestication. Could domestication really happen in just eight generations? (Apparently.) Domestication must just affect the brain and not the rest of the body, right? (Apparently not – domesticated foxes can have characteristic coat color changes, floppy ears, and curly tails, similar to morphologic differences between dogs and wolves.) But a research population of domesticated foxes hasn’t been maintained since the sixties just because they are cute. We’re still learning things from them. Like what? Get ready for some well-aged papers; a lot of this work was done back in the eighties.

Hormone and neurotransmitter soup

We use the hormone cortisol as a marker of stress: if you have more cortisol in your blood, you’re probably more stressed. It turns out, perhaps not surprisingly, that domesticated foxes have lower basal levels of cortisol than their unselected counterparts (Oskina, 1992). Their cortisol levels also don’t go up as high during a stressful experience as do the cortisol levels of unselected foxes (Harri, 2003). Personally, I think cortisol is going to play a key role in the mechanism of why domesticated animals are less flighty than wild ones. Cortisol levels influence the production of adrenaline: if you have more cortisol in your system, you are liable to make more adrenaline (Kvetnansky, 2009). If you have more adrenaline in your system, you are going to react more strongly to scary stimuli – in other words, your flight distance is going to increase. (Quick review – domesticated foxes were bred by selection for decreased flight distance from humans.) My friends and I noticed during our highly stressful first year of veterinary school, when our cortisol levels were certainly high, that were were inexplicably jumpy. One friend reported that she was so startled by the noise of a dropped glass that she actually screamed.

As for the ever-popular serotonin, the “happy hormone,” domesticated foxes have more of it in their midbrains and hypothalamuses (Popova, 1991). Yes, the same hypothalamus that is the beginning of the hypothalamic-pituitary-adrenal axis, which ends in the release of cortisol. Oh, and which is inhibited by having more cortisol already in the system, in a negative feedback loop.

There is nothing cuter than a baby domesticated fox

Wolf cubs have a much shorter socialization window than dog puppies, and this might be part of why it is so difficult to socialize a wolf cub to humans. It turns out that unselected fox kits have a shorter socialization window than domesticated fox kits, too. Prime socialization time in both lines seems to start around 30-35 days, when the kits can see and hear and are mobile enough to explore their surroundings. Like most very young animals, fox kits of this age aren’t as fearful as their adult counterparts; they have a chance to learn what is dangerous and what is not in their particular environment. A longer socialization window gives you more chances to learn that a variety of beings are not dangerous to you, but in the wild it also gives you a greater chance of getting eaten by something that is dangerous to you when you wander up to say hello to it.

Domesticated fox kits start showing fear of new objects after age 60-65 days. Unselected kits, on the other hand, start fearing novel things at day 40-45 (Belyaev, 1985). We don’t know what exactly causes this difference in a preprogrammed socialization window, but it’s very helpful to have these populations as we look for the cause.

An even lower level of programming

In recent years, researchers have had new tools to use in exploring the mechanisms of domestication in foxes, especially since the canine genome was sequenced. Comparing gene expression in the wolf and the dog is problematic, because they necessarily live in such different environments. Comparing gene expression in two populations of foxes raised in identical conditions is potentially much more fruitful. This research is in the early days. But as we learn more about the canine genome I think we’ll start finding some really interesting differences between the lines of domesticated and unselected foxes. My personal belief is that we’ll find subtle differences – maybe, rather than differences in actual genes, we’ll see changes in promoter sequences, which cause significant genes to be up or down regulated.

We’ve learned a lot from the Russian domesticated foxes so far, but we have a long way yet to go. We still have no real idea exactly what is at the root of the difference between a domesticated and undomesticated animal. Does the change in development affect cortisol and serotonin levels, or vice versa? Does just a single genetic modification cause all the physiologic changes we see? Or are we looking for a set of modifications? Hopefully the new genomic tools we’re developing will allow us to get to the bottom of the mystery.

References

OSKINA, I., & TINNIKOV, A. (1992). Interaction between cortisol and cortisol-binding protein in silver foxes (Vulpes fulvus) Comparative Biochemistry and Physiology Part A: Physiology, 101 (4), 665-668 DOI: 10.1016/0300-9629(92)90341-M

Harri M., Mononen J., Ahola L., Plyusnina I., Rekila T. Behavioural and physiological differences between silver foxes selected and not selected for domestic behaviour. Animal Welfare. 2003:305-314.

Kvetnansky, R., Sabban, E., & Palkovits, M. (2009). Catecholaminergic Systems in Stress: Structural and Molecular Genetic Approaches Physiological Reviews, 89 (2), 535-606 DOI: 10.1152/physrev.00042.2006

POPOVA, N., VOITENKO, N., KULIKOV, A., & AVGUSTINOVICH, D. (1991). Evidence for the involvement of central serotonin in mechanism of domestication of silver foxes Pharmacology Biochemistry and Behavior, 40 (4), 751-756 DOI: 10.1016/0091-3057(91)90080-L

BELYAEV, D., PLYUSNINA, I., & TRUT, L. (1985). Domestication in the silver fox (Vulpes fulvus Desm): Changes in physiological boundaries of the sensitive period of primary socialization Applied Animal Behaviour Science, 13 (4), 359-370 DOI: 10.1016/0168-1591(85)90015-2

The ethics of dog breeding: to breed or not to breed?

2011-07-23T17:41:00.000-04:00

It’s challenging to breed purebred dogs well. You have to balance appearance, health, and temperament, and of course by “health” I actually mean “2598237 different possible inherited diseases.” You breed or buy the best animal you can (no small task in itself), you compete with it to prove its ability and conformance to the breed standard, and then when it is an adult the time comes to breed it. Before you breed, you have to make sure the animal is physically healthy. You perform perhaps thousands of dollars worth of tests towards this goal. If your star fails any one of them, you should consider not breeding it, even if it is otherwise a great breeding prospect. If it fails a really important test — like the assessment of the likelihood of developing hip dysplasia in a breed that is notorious for its hip problems, like the golden retriever — then you really shouldn’t breed the animal.

Time was, dog breeders had big kennels, with dozens of dogs. If one of them turned out to have an inheritable health problem, it was fairly easy to just remove that animal from the breeding program. After all, if you have 50 dogs and can only breed 49 of them, what’s the big deal? These days, people have less land, and dog breeders tend to have smaller numbers of dogs. So what happens if you are the owner of a single, beloved pet and you really want to try to improve the breed by having a litter from this pet? You show, you compete, you have health tests, and the animal fails the test for healthy hips. Now it’s not just a question of not breeding a single animal. Instead, it’s a question of not being able to breed at all, unless you get another dog and start over. What if that one has a health problem too, and you really don’t want to have three dogs in your house?

It’s a tangled issue. Personally, I think dogs do better in homes than in kennels, generally speaking (although I recognize that there are some private kennels out there containing some very happy dogs). But I also think that if we are going to be selecting dogs for beauty, as we do with show dogs, we have a responsibility to not let health fall by the wayside. Making the breeding of healthy dogs easier is a good thing. It’s sad to think that the fact that more dogs are living inside as pets makes breeding responsibly more difficult.

The art of dog breeding: Puppy has two daddies

2011-07-19T13:12:00.000-04:00

Not just every puppy has two daddies. How would it happen?

It’s a long story, so stick with me. Let’s say you’re deeply involved in the dog world, and love a particular breed of dog. You breed to improve that breed. You have a young bitch that you are considering breeding. You start out by taking this bitch to dog shows, doing that circuit until the bitch has earned her championship after a number of wins at different shows. This shows that the bitch is conformationally excellent enough to be worth breeding. You may also work with the bitch in some other area, like competition obedience, tracking, or agility.

When the time comes to breed, there is more work to do. You have to make sure the bitch is genetically good material. You know what problems are common in the breed, so you test for those. There are some problems (like hip dysplasia) which are so common that breeders test for them in almost every breed; there are some that are more rare. Some tests are genetic tests done on DNA samples. Some are just the sorts of tests any vet might do to see if the levels of different chemicals in the blood are within normal ranges, or if they are suggestive of certain conditions. All these tests have to be done on both sire and dam.

Who’s the sire? You should pick out a sire that complements this bitch well. No animal is perfect. If the bitch’s biggest failing is her less than perfect hip conformation, then the sire should have really exceptional hip conformation, to balance that problem out. They should not be too closely related, either.

The right sire may live across the country or across the world from the bitch. If he’s far away, artificial insemination will be necessary (although some animals get transported quite a distance for sexual liaisons, and some bitches are artificially inseminated even though the dog is in the next room). When exactly should this occur? If the dog is prime breeding material, his semen will be very expensive, not to mention the fees for implanting it (more on that later). So you want to do it as few times as possible.

It’s also important to know as precisely as possible when the bitch ovulated, because this helps predict when she will give birth. So ovulation prediction is an important part of this process. It involves blood tests over multiple days, done by a veterinarian.

Once you know what the bitch’s three fertile days will be, how will you get the semen in? You can choose natural service (the old fashioned method), artificial insemination into the vagina, or intra-uterine insemination (surgical insemination directly into the uterus). This last approach is the most reliable, although of course it is also the most invasive and expensive.

If you don’t choose natural service, you may be getting either fresh semen (from the dog in the next room), fresh chilled and shipped overnight (from somewhere on your continent, collected the previous day), or frozen (from anywhere in the world, and possibly as venerable as twenty years old). Why would you artificially inseminate fresh semen, if the dog is right there? Some bitches can be cranky if they don’t approve of the dog on offer, and there can be violence. The owner of an expensive (or well loved!) stud dog might not wish to risk his injury.

Now it comes down to it. Many breeders will have spent thousands of dollars to get to this point. Some will have spent tens of thousands. They really, really want to have a successful impregnation. The fresher the semen, the more reliable it is. If the best possible sire is only providing frozen semen for whatever reason, the chances are significant that the bitch will not get knocked up. So what do you do?

On the bitch’s first fertile day, you use the frozen semen from the preferred sire. You hope that all her eggs get fertilized by this semen, but if some are left over, you call in the backup sire, someone local who can provide fresh semen. Hopefully any eggs that failed to get fertilized by the first sire will get handled by the second. You may well end up with puppies from each sire in the litter, but that’s fine; you can DNA test them to know who’s sired by whom. And that is how a puppy can have two daddies, or, at least, a litter can.

(Note: I skipped over the numerous ethical issues brought up in this story. For today, I just wanted to share with you some of the surprising tools available to dog breeders today.)

Neurology rotation

2011-07-11T06:26:00.000-04:00

I just completed my two-week neurology rotation. You might think that, because I love dog brains, this would have been right up my alley. Actually, I love the parts of brains that help us learn, fear, trust, and love. Veterinary neurology, on the other hand, is a big game of Hunt the Lesion. A dog comes in uncoordinated and with a head tilt. Where in its brain, cranial nerves, or spinal cord is the problem?

A good neurologic exam can localize the problem to the cerebrum, the cerebellum, one or more of the cranial nerves, the spinal cord in front of the front legs, the spinal cord over the front legs, the spinal cord between the front and back legs, the spinal cord over the back legs, the spinal cord behind the back legs, or something more general (a diffuse muscle, nerve, or muscle/nerve junction problem). Once we had an idea where the problem was, we usually sent the animal in to the MRI scanner (a luxury at a large referral hospital; we received a lot of animals coming in just for the MRI, referred from places that don’t have them). This allowed us to see exactly where the lesion was, and to get some information about what kind of lesion it was (intervertebral disc extruded into the spinal canal? A stroke? Cancer?).

I did enjoy neurology, even though Hunt the Lesion isn’t my favorite game. There was a surprising amount of basic medicine to learn; I got a lot more comfortable with how to manage post-surgical animals (we did lots of vertebral surgeries), as well as how to approach a diagnosis (young animals are more likely to have congenital or infectious problems or to have eaten toxins; older animals are more at risk for stroke or cancer). Practicing basic medicine is always good! So it was an enjoyable rotation, but now I am really looking forward to my upcoming four whole weeks of elective time.

Bringing them back from the edge

2011-07-03T15:04:00.000-04:00

When I was on my small animal medicine rotation a few months ago, I had a patient with bad kidney disease. This little dog was sixteen years old — about a hundred years in human terms — and very frail and thin. I got into the habit of calling her “Grandmother,” because she seemed so venerable. None of us had very high hopes for her long term recovery, not even her owner; we were just trying to give her a shot at a few more weeks of life by rehydrating her with IV fluids.

Two of the residents disagreed about our goals for this dog. One of them wanted to send her home as soon as possible, arguing that she didn’t have much time left and shouldn’t spend it in the hospital. The other argued that we should give the dog a few more days to wean her off of her IV fluids properly before sending her home, to give her the best chance. The second resident ended up handling the case, and the dog stayed in the hospital for those few extra days for some extra care before going home.

This week I encountered the same dog (and the same resident) in the hospital for a recheck. I hardly recognized the dog, and not just because I had never expected to see her again. She had put on weight and looked filled out and healthy. She was moving around the hospital under her own steam (when she was my patient, I had had to carry her outside to pee) with a happy trot. She was bright-eyed and curious. Her owner reported that she was even playing sometimes.

“Look,” the resident said, “sometimes we really can bring them back from the edge.”

At age sixteen, this dog doesn’t have much time left no matter how you look at it, but that doesn’t mean it was time to give up on her. The lesson had personal meaning for me. My fifteen year old cat, Kai, is currently battling kidney disease, heart disease, and stomach cancer (gastric lymphoma). Each of these diseases is serious; each has almost killed him at one point. Each time I have to decide whether to continue with him, I ask myself whether I am being silly, whether it is time to give up. The treatments are not invasive, but is there any point to them when I may just have weeks left with him? Then I look at how good his quality of life is (he steals food off my plate, sneaks outside when I am not looking and eats things he shouldn’t in my back yard, and uses foul language to tell the dogs what he thinks of them) and remember the lesson of the little sixteen year old dog. Sometimes, even when things look bleak, animals can make a remarkable recovery for a little while. If the treatments are not invasive and the animal is not in pain, it can be worth trying.

How to give a horse his eye medications, or, What is an SPL?

2011-06-14T19:44:00.000-04:00

One of my patients on my Large Animal Medicine rotation had a very sick eye, for which he needed approximately 9187346 medications every few hours. Getting eye meds into a horse is not easy. Their eyelid muscles are so strong that we routinely nerve block their eyelids before doing eye exams, because otherwise it would be impossible to hold their eyes open. This is, of course, not practical for hourly medications. But they hate having things put in their eyes (who doesn’t?), and they can throw their heads up very high in addition to squeezing their eyes tightly shut. This particular horse was especially tall, as well, and could hold his head well out of my arm’s reach.

The solution in these cases is to put in a sub-palpebral lavage (SPL). “Palpebral” is the science word for “having to do with eyelids,” so an SPL enables you to lavage (wash) underneath an eyelid. This is how it works: you take a big needle, which you stick through the horse’s upper eyelid coming from the underside (the side facing the eye). You use the needle to pull a slender tube through the eyelid, so that its end is sticking just under the eyelid, and the rest of the tube runs up over the horse’s head and down its neck. You affix the far end of the tube to the horse’s mane, with an injection cap on the end. In my hospital, a popsicle stick is involved in the tube/injection cap/mane connection, to stabilize the entire apparatus.

Now when you want to give an eye drop, you can use a syringe and needle to inject it through the injection cap into the tube. You then inject air after it to push it through the long tube and into the horse’s eye. They do find this annoying, and once they learn the routine, will dance around in an attempt to not let you actually stick the needle into the injection cap on their neck. However, getting at their neck is worlds easier than getting at their eye. My patient was relatively good for the whole thing, so that I could do it without asking anyone else to hold his head. He always got a cookie after each medication administration (which added up to a lot of cookies in the end). When it was over he would immediately stick his nose agaist my shirt to get his treat. The SPL was annoying for all concerned, but so much better than the alternative.

Shelter medicine externship

2011-06-04T17:59:00.000-04:00

I recently spent two weeks of elective time at a shelter medicine externship at a different vet school. Half the time was spent in academic pursuits on campus — going to journal club, going to talks and lectures about shelter medicine, etc. The other half was at the shelter, doing high volume spay/neuter, temperament tests, treating sick animals.

Highlights:

Pulling worms out of a kitten’s butt (“Wow, can I?”)
STRAY GOLDFISH. It is more amusing not to explain, but I will say that it was found in a ditch in a grocery store parking lot.
Ratlings! Five week old foster rats came in for a visit. They had been well socialized and were extremely friendly. I badly wanted to adopt one, but suspected it would not get along with my cat.
Seeing exactly how fast 8 week old kittens recover from spay/neuter surgery. Spay surgery is no small deal, but those girl kittens were literally climbing the walls of their cage 30 minutes later. I am sold on pediatric spay/neuter.
Helping to set up play groups of shelter dogs and getting to watch them play together. It was lovely.

Shelter medicine is in large part population medicine, or herd health. Of course you do need to pull the occasional worm out of the rectum of a kitten, but you also need to think about how to keep animals out of the shelter in the first place, and how to keep them from getting sick once they are there. Daily rounds in my vet school’s small animal hospital are about the specifics of what diagnostics were done on an animal yesterday and what needs to be done today; daily rounds in the shelter were about why an animal hadn’t been moved to the adoption floor yet or how to deal with the placement of a feral cat. I knew that shelter medicine had a large preventative component to it but was not prepared for quite how large the component actually was. I was enthusiastic; I really like this kind of medicine.

$200 worth of oops

2011-05-29T16:19:00.000-04:00

This Saturday I was “on duty” in the large animal hospital, meaning that I was in the hospital for about 12 hours, theoretically helping with the treatments on all the animals (mostly horses, but we have gotten a few baby alpacas, or crias), along with one of my rotation mates. I say ”theoretically” because in practice, I just worked on my actual patient, a post-colic surgery horse who was extremely time consuming. My rotation mate and the techs handled the other animals, who needed many fewer treatments.

My horse was hooked up to a bunch of bags of IV fluids. In our large animal hospital, we suspend all the fluids from a hanger on the ceiling, and they run along coiled (therefore extendable) lines into a catheter in the horse’s neck. This way the horse can walk around his stall without getting his legs tangled, although the lines will inevitably tangle among themselves if you have multiple of them, which this guy definitely does. And with horses, the amounts of fluids and medications going in are fabulous. He had two five-liter bags of fluids hung at all times, plus a one liter bag of antibiotics, and a one liter bag of painkillers. This is aside from the medications I needed to inject into his catheter periodically, plus the oral meds I had to put down the tube which runs from his nose into his stomach.

The time came to change one of the bags of fluids. One of the techs stood outside the stall and lowered the hanger with all the bags. I removed the empty bag and hung the new one (with much grunting, as it was over my head and heavy). I disconnected the line from the old bag and went to connect it to the new bag — but since the line was also still connected to the second bag of fluids, it immediately started spewing saline all over the stall. I stuck my finger over the open tube to stop the flow just as the tech yelled “It’s sterile, don’t touch it!”

Well, I did know that you shouldn’t be sticking your finger over a sterile tube opening, but I had panicked and done it anyways. I stood there looking sheepish while the techs conferred. Yes, the line would have to be replaced. A new line cost $100. We obviously could not charge the client for this. The hospital would have to eat it. (The hospital is currently not profitable, which made me feel extra guilty.) These things happen when you are learning, but it is still super embarrassing. Also, changing the line was very complicated, and therefore annoying for the tech who did it.

Later in the day I was giving my horse his IV medications, injecting them into the new line. The second medication started turning into a solid powder inside the clear tube. It was precipitating! Just like in chemistry class! Except that that is bad to put into a horse’s bloodstream. I stopped and called a tech. I should have flushed the line with saline between injections. Oops. I flushed the line again and again to get all the precipitate out, but some was just too firmly adhered to the side of the tube. So, you guessed it, we had to change the line a second time, for another $100 eaten by the hospital.

So much to learn! So many embarrassing mistakes to make! I will never make these two mistakes again, though, I am pretty sure.

That is what is known as irony

2011-05-24T15:18:00.000-04:00

I knew I would leave something behind in the town five hours from home where I did my shelter medicine externship. It was just a question of what. The answer: my wristwatch.

I hate wearing watches, but they are essential in the hospital for taking respiration rates and pulses. My friend is bringing my watch back to me this weekend, so I figured I’d try to tough it out watchless this week on large animal medicine. How many heart rates could I have to take? One a day? I could borrow a watch for that.

This morning I received my second patient, a foal aged 20 hours. His mom (a first time mother) was not letting him nurse. If baby horses don’t get a chance to ingest colostrum while their mom is still making it, before she switches to making normal milk, they miss out on essential antibodies and can die of infection. This is not true for human babies, who get their antibodies through the placenta.

We tested the baby, and indeed his IgG level, which is indicative of the amount of antibody in his blood stream, was almost nil. The solution: give him antibiotics, and give him a plasma transfusion.

I was enthused. I had never seen a plasma transfusion! And now I was going to get to actually do one! The tech said a little dourly, “You may find it a little less exciting once you see how it works.”

This is how you do a plasma transfusion in a neonatal foal: you hook it up to IV plasma and make a vet student watch it drip in for two hours. Every five minutes, the student has to — wait for it — take a pulse and respiration rate, to make sure the baby is not getting fluid overloaded.

It turns out that my cell phone doubles as a stopwatch. Not the most convenient thing to use around large animals, though.

Do not kidnap wild animal babies!

2011-05-23T13:18:00.000-04:00

Since spring is upon us, at least in my part of the world, I offer a public service announcement: do not kidnap wild animal babies! If you see unattended baby birds, baby bunnies, etc., please do not pick them up and bring them in to a wildlife clinic. Their parents are very likely to return to take care of them after you leave, and they will do better in the wild than in a clinic. Moving them will probably do more harm than good!

Wild Baby Rescue Center, Inc. has a nice summary of how to know when baby wildlife needs your help.

He’s a lover, not a fighter: outreach for the prevention of dog fighting

2011-05-18T21:10:00.000-04:00

[This is the presentation I gave at a shelter staff meeting this week, as part of my shelter medicine externship.]

How can we redirect inner city kids away from using their pit bulls for dog fighting, and towards other activities? I looked into two programs that exist to reach out to youth and do exactly that. These programs focus on prevention of dog fighting, on educating kids before they decide that dog fighting is cool, rather than focusing on the punishment of dog fighters.

The first program I looked at is the End Dogfighting campaign from the Humane Society of the United States. The End Dogfighting campaign has several different arms:

The Pit Bull Training Team provides alternative activities for youths with pit bulls (or, presumably, other breeds). Set up as a weekly class, the PBTT introduces kids to obedience and agility, and also provides some socialization for the dogs (since fighting dogs, obviously, often have poor social skills with other dogs). For students who do well and stick it out to the end, there is a Canine Good Citizen (CGC) test that they can take. If they pass, they receive a CGC title for their dog from the AKC, certifying that they have a well trained dog. Graduates of the class are encouraged to stick around and mentor new students.
The Humane Education arm of the campaign is an 8 week curriculum for middle school students. It’s intended to be a fun set of classes, with mock game shows, videos, and hands on projects. The message of the class is that dog fighting is a crime, it’s violent, and it’s animal cruelty.
The First Responder Outreach arm of the campaign is aimed at postal workers, utility works, and public works employees — the people who are out in the neighborhood who might encounter signs of dog fighting rings. The HSUS provides posters with information about what to look for, such as how to recognize the fighting pit where dog fights occur. The HSUS may also provide a presentation if asked.
The Law Enforcement Outreach arm of the campaign provides a $5,000 reward for tips leading to the conviction of a dog fighter; law enforcement training classes; a database with the names of known dog fighters; grants for handling seized animals (controversial, as the HSUS recommends that such animals be immediately euthanized); and prosecutor training.

The End Dogfighting Campaign began in 2006 in Chicago. Since then it has expanded to Atlanta and Philadelphia. So far, the campaign is focused on big cities. It seems unlikely that we’re next on their list. However, the HSUS freely provides materials for download to let other groups try to implement individual arms of the campaign.

I also looked into the Lug Nuts program, which is informal weight pulling contests in cities with dog fighting problems — again, providing alternative activities for people to do with their pit bulls. In a Lug Nuts contest, children’s sleds are loaded with food until they are very heavy. Dogs (not always pit bulls, although pits are very muscular and tend to be very strong dogs) are hooked to the sleds with special harnesses. The dog that pulls the farthest wins. The food can also serve as a prize, and the prize can be doubled for animals who are spayed or neutered. As the web page for the program says, there is excitement! Machismo! Thrill! The competitive aspect of Lug Nuts may be an important way to draw people in.

Sue Sternberg started Lug Nuts in New Haven in 2002. It is associated with a Training Wheels program, which brings pet supplies and veterinary services into underserved areas, and takes the opportunity to also bring some education about positive reinforcement training to dog owners.

So who should be going into inner city communities and telling people about these programs to change how they interact with their dogs? I am pretty sure that if I tried, I’d get laughed at. The End Dogfighting campaign solved this problem with the creation of Anti-Dogfighting Advocates (ADAs), graduated students from the program. They encourage people to come in to the weekly classes, and check in on them during the week to keep their interest up. There is definitely a bootstrapping problem here. Who goes out and convinces people to go to the first classes? But the approach of keeping community members involved even after graduation is a nice one.

I like the positive approaches of these two programs. Positive reinforcement works better than punishment! I’d love to see both programs expand to more cities.

The Purebred Paradox, part four: What can be done?

2011-05-14T15:58:00.000-04:00

(Continued from part three.)

Below are my musings on some of the talks at the recent conference, The Purebred Paradox: on the health and welfare of purebred dogs. Specifically, these talks delve deeper into ways some of the speakers thought we could move forward.

Professor Sir Patrick Bateson: “Problems of dog-breeding and what to do about them”

In his keynote address, Professor Bateson called for for “a public awareness and education campaign.” In his talk and in later discussions, the question of whom to educate was raised. Three interest groups were identified: dog owners, dog breeders, and judges of dog conformation competitions. Again and again, speakers at the conference returned with frustration to the question of how to educate dog owners. Once the bulldog has been purchased and the new puppy brought to the veterinarian for its wellness exam, it is too late. How do you educate people about healthy breeds before they bring home and bond with a new dog?

Patricia Haines, DVM: “Canine Genetics, Behavior and the role of the parent club”

Dr. Haines, a veterinarian and breeder of pointers, talked about parent breed clubs. Both the American Kennel Club (the AKC, the largest registering body of American purebred dogs) and the Kennel Club (the KC, the AKC’s British counterpart) are made up not of direct members but of member clubs, or “parent clubs.” These clubs mostly (but not entirely) represent breed specific clubs, such as the Golden Retriever Club of America.

Dr. Haines made the point that work for change would be more effective with the parent breed clubs, rather than with AKC judges. In fact, she said, many breeders joke that the judges don’t really know their breed well. It is the parent clubs which are the guardians of the breed standards, and, perhaps more importantly, the interpreters of them.

Dr. Haines’ insight highlighted, in my opinion, the usefulness of working with members of the dog breeding community. That community is a complex one which can be difficult to fully understand from the outside.

Gail K. Smith, VMD, PhD: “Efficacy of hip dysplasia screening: An animal welfare imperative”

Dr. Smith is the veterinary surgeon who designed the PennHip screening system for hip dysplasia. The more traditional Orthopedic Foundation for Animals screening system involves subjective judgement of a dog’s hips as poor, fair, good, or excellent. PennHip, on the other hand, provides an objectively determined “distraction index,” a numerical measurement of the amount of hip laxity (where more laxity implies worse disease). Dr. Smith explained that his PennHip system is particularly useful for genetic studies of hip dysplasia because it is a better measurement of phenotype, for use in correlation to genotype. In other words, if you want to study what genes produce hip dysplasia, an objective numerical value describing the individual animal’s anatomy is more useful than a subjective value like “fair.”

Of course, the question arises: can other characteristics be measured using numerical scales? How do you measure the flatness of a bulldog’s face? There is work to be done in this area.

Steve Zawistowski, PhD, CAAB: closing remarks
PhD behaviorist Dr. Sawistowski explicitly identified a fissure between those who breed dogs and those who identify themselves as members of animal welfare organizations. He said, “We are going to have to heal that fissure before we can heal the dogs that we all know and love.” This conference did a great job of outlining this goal and the current situation and identifying priorities to be addressed.

The Purebred Paradox, part three: Analyses of the situation

2011-05-13T13:14:00.000-04:00

(Continued from part two.)

Below are my musings on some of the talks at last week’s conference, The Purebred Paradox: on the health and welfare of purebred dogs. Specifically, these talks delve deeper into what some of the current health risks are for purebred dogs, and why.

Brenda Bonnett, BSc, DVM, PhD: “Breed risks for disease in purebred dogs”

Dr. Bonnett is an epidemiologist who worked with “12 years of [health] data from over 200,000 dogs yearly,” obtained form Agria Pet Insurance in Sweden. Her talk was fascinating; placed as the very first presentation, it was a great introduction to the conference. She showed a series of graphs comparing the risk of different diseases in different breeds. Using the pet health insurance data, she could identify some risks as part of the risk of “being a dog” (diseases equally likely to occur in any breed) versus the risk of, for example, “being a German shepherd” (hip dysplasia, much more likely to occur in that breed than in most others). These graphs made the case very clearly that many breeds have risks of particular diseases.

The graphs were also an excellent way of demonstrating which diseases should be prioritized in particular breeds. She talked specifically about Cavalier King Charles spaniels, a breed which is prone to a particularly painful brain disorder called syringomyelia. Syringomyelia in CKCS was publicized in Pedigree Dogs Exposed and has been receiving a great deal of attention as a result. But her data suggested that another breed problem, heart disease, is much more prevalent. Syringomyelia, a disease in which your brain is squeezed out of your skull because your head is too small, is certainly very sexy, but if a CKCS is much more likely to die of heart disease, perhaps the issue of the heart disease should be addressed first.

But we already knew that different breeds get different diseases, right? When you are picking the breed of your next puppy, if you’re doing your research, part of your decision is whether you can deal with the risks of that particular breed. Is it more likely to get hip dysplasia? Heart disease? Cancer? Dr. Bonnett made the point that people will accept some types of risk, and some levels of risk, but not others. Life has some risks that you can't avoid; playing with sticks can be risky for a dog (GI obstruction! cracked teeth! splinters migrating into the sinuses!) but people accept those risks because they are part of being a dog. However, owners also accept the risks which are part of being a particular breed. Should they?

Dr. Bonnett concluded her talk by telling the story of a Bernese Mountain Dog (berner) owner who had come up to her after a previous talk. This woman had said that she had known that berners suffered from an increased rate of cancer, but had had no idea quite how bad the situation was until she listened to Dr. Bonnett’s presentation. However, this woman said, she would keep owning berners, because they were her breed. One of the themes of the conference was certainly the deep loyalty people have to “their” breed. (I completely understand it, as I feel that way about golden retrievers.)

Ilana Reisner, DVM, PhD, DACVB: “Unintended consequences of breeding for conformation: Owner-directed aggression in English Springer Spaniels”

Dr. Reisner is a veterinary behaviorist who presented a case study of an owner-agressive English Springer spaniel. This breed is particularly known for what has been called “springer rage,” sudden fits of aggression to the owner. The subject of Dr. Reisner’s presentation, Pluto, had bitten every member of the household, including the 80 year old grandmother. Dr. Reisner joked, “It wasn't too bad, just a few amputations.” She made the point that, while the conference was focused on dog welfare, when people live with dogs who are suffering or who have behavior problems, human welfare is also affected.

Frances O. Smith, DVM, PhD: “The development of dog breeds: Why and how people breed dogs”

Dr. Smith was a veterinarian, Labrador retriever breeder, dog show judge, and theriogenologist. (A theriogenologist is a veterinary specialist who has advanced training and board certification in breeding and reproductive problems.) She was clearly an exemplary breeder. She talked about the best dog she ever bred, who was a conformation champion and a performance champion. Dr. Smith emphasized again the importance of breed specific traits in the hearts of owners and breeders. The breeds must stay unique and recognizable. Any other solution to the problem is going to be very hard for many dog lovers to accept.

Dr. Smith seemed to have been asked to speak as a representative of the breeder side of the debate. I wish that we could have heard from some breeders at the show who were not cherry-picked to be non-controversial, however. The Labrador is a sporting breed, and sporting dogs tend not to suffer from breeding for extreme characteristics, as they are often expected to still be able to do work. (To understand what is meant by “extreme characteristics,” enjoy this post by the producer of Pedigree Dogs Exposed about the Neapolitan mastiff.)

Frank McMillan, DVM, DACVIM: “The impact of puppy mills on the welfare of purebred dogs”

Dr. McMillan is an internal medicine specialist and employee of Best Friends animal shelter in Utah. He talked about the widely publicized problem of puppy mills (high-volume, commercial breeders, who I’d argue are irresponsible by definition). He showed a number of disturbing photos of adult breeding animals taken from filthy and unhealthy circumstances at various mills.

Dr. McMillan’s main point was that the psychological damage done by lack of socialization to adult breeding animals in high volume breeding facilities is severe and should not be overlooked. Even dogs maintained at sparkling clean facilities are not given the socialization time they need as puppies to function properly once they are taken out of the puppy mill as adults. He read accounts and showed photos of these adult rescues, and demonstrated their complete inability to bond with their new owners after months, some even unable to be housebroken as they could not be approached with a leash to be taken outside. He argued convincingly that many of these dogs should be considered victims of post-traumatic stress disorder. No amount of regulation or oversight by the USDA will change this fundamental lack of socialization of dogs kept in situations where they do not get a chance to experience the world outside of their kennel.

(To be continued.)

The Purebred Paradox, part two: What’s the problem?

2011-05-10T06:25:00.002-04:00

(Continued from part one.)

I recently attended The Purebred Paradox: on the health and welfare of purebred dogs. These are my musings on a few of the talks at the conference, specifically those detailing what exactly the problem is with current methods of dog breeding.

David Sargan, PhD: “The RSPCA report on purebred dog breeding: Conformational selection and inbreeding in dog breeds”

David Sargan summarized the 2008 RSPCA report on purebred dog breeding. Before the release of the Pedigree Dogs Exposed documentary, the RSPCA had not really focused on issues in purebred dog breeding. This report represents their initial attempt to grapple with how they were going to address these issues.

The report identifies two welfare issues: exaggerated anatomical features that reduce quality of life, and an increased prevalence of inherited disorders. It also discusses current screening practices. Standardized screening is available for eye and hip disorders, among others. These screens are used only by a self-selecting population, however, so are not useful for a description of the true prevalence of a particular disorder in the population. For example, dogs which are not intended to be bred — “pet quality” dogs — are less likely to be screened, though they may well have a genetic disorder. Dogs with unsubtle signs of disease may also not be screened, but simply treated. DNA tests are being developed for many diseases, but many diseases exist for which no DNA test has yet been developed. Of course, many diseases do not lend themselves to DNA tests, as they may be multifactorial in origin, due to many different genes, or to interactions between genetics and environment.

The report outlines possible ways forward. Among its many recommendations are more systematic data collection; an increase in genetic diversity, both by limiting inbreeding and by opening the kennel club stud books (allowing offspring of unregistered dogs to be registered as purebreds); and work to improve the screening tests available.

The report concludes: “the most important element is to ensure that all stakeholder groups buy into the process and fully support the action(s) they need to take. This is the challenge that lies ahead.”

Jemima Harrison: “Pedigree Dogs Exposed: The Aftermath”

The producer of the hugely influential Pedigree Dogs Exposed spoke on the aftermath of the film. Actually, she started by outlining the premath, noting that change has been called for in pedigree dog breeding for over 100 years, and including newspaper stories and other references. She wondered if her film had caused enough change to really get and keep the ball rolling — has the sea change happened? Or is there more work to do?

She wasn’t sure, but she did include a video of Fiona, “the first mongrel to be shown at Crufts.” Fiona is the first low uric acid Dalmation to be shown at the number one UK dog show. The LUA Dalmations are the product of a single outcross to a pointer, and subsequent selective breeding to remove the gene for a genetic predisposition to kidney stones whch is present in every Dalmation except for those with this pointer heritage.

(Continued in part three.)

The Purebred Paradox, part one: Background

2011-05-08T21:13:00.000-04:00

In 2008, the BBC aired Pedigree Dogs Exposed, a documentary about breeding practices in purebred dogs. The documentary suggested that health problems are on the increase in purebred dogs, and that many of them are avoidable. Specifically, some problems are due to limited gene pools and unintentional fixing of traits such as predisposition to cancer; others are due to intentional breeding for extreme characteristics like flat faces or heavily wrinkled skin. This documentary triggered a strong reaction from the public, and the beginnings of some changes in how members of the UK breed clubs approach breeding dogs.

It also triggered a negative reaction from the British Kennel Club, and a great deal of controversy. The two sides of the debate are, in my own words:

Dog breeds are part of our heritage and are important to us. Each breed has its defining characteristics (the unique color of the golden retriever’s coat, the size and shape of the Great Dane, the jowly face of the English bulldog). These characteristics are what make each breed unique, and should be celebrated and maintained. I’ll call the people on this side of the debate the dog breeders, at risk of a gross overgeneralization.
The health of many purebred dogs is endangered both by consequences of inbreeding (such as overrepresentation of genes for cancer in Bernese Mountain dogs) or by breeding for extreme traits (such as the extremely flat face of the pug). We should start prioritizing the health of our purebred dogs over maintenance of breed purity. I’ll call the people on this side of the debate the advocates for change, although many dog breeders take this viewpoint as well.

Last week, I was privileged to attend a conference in Washington, D.C., called The Purebred Paradox: on the health and welfare of purebred dogs. This conference was intended to move the debate, which had begun in the UK, to this side of the ocean. By my estimates, however, more than a quarter of the speakers and attendees hailed from overseas.

One of the unstated goals of the conference seemed to be to get the two sides, breeders and advocates for change, to start a real discussion. In my opinion, the discussion was hampered from the start by the fact that the conference was not organized by breeders, and was by no means neutral ground. Representatives from the breeder camp were underrepresented, and seemed as well to have been selected to be not too controversial. Everyone was very civil, but I didn't feel like anyone’s mind was really changed.

That didn’t stop me from having two of the most enjoyable days I’ve spent in months or even years. About half of the speakers were veterinarians, and vets were very well represented at the conference overall, which surprised me. It has been my observation in veterinary school that veterinarians are as a general rule not greatly worked up by breeding practices — it’s part of the profession’s usual refusal to judge the husbandry decisions of an animal’s owner in public unless truly abusive. Apparently some vets are coming to see some breeding practices as crossing that line into abuse, and are interested in seeing change.

It shouldn’t need saying, but I will say it, just to be super clear: I have nothing against breeding purebred dogs in theory, and there are quite a few extremely responsible, ethical breeders out there — I met a lot of them at this conference. But there are breeders who do seem to be blind to the discomfort that breeding for extreme characteristics can cause dogs, and there are some breeds that I believe cannot be humanely bred under current practices, though could certainly be humanely bred with some conservative modifications to the breed standard (or to interpretations of it). I am not anti-breeder, but I am very much against certain breeding practices.

(To be continued.)

The case of the jaundiced terrier

2011-05-04T09:20:00.000-04:00

It was 6:30 am on the last Saturday of my small animal medicine rotation. I had one patient in the hospital to care for that morning, but I was also scheduled to take pick-ups that day — taking on as new patients half of the animals who were transferred to the medicine department that morning from the emergency and critical care department. A rotation mate of mine would take the other half. The transfer list had two animals on it, and since I had gotten to it first, I could pick which I wanted. Feeling relatively bright-eyed and bushy-tailed after a slow week with not many cases, I chose the Boston terrier whose one-word problem (about all the transfer list has room for) was that she was “jaundiced.” Jaundice, or having yellow skin and mucus membranes, suggests a liver problem, as the liver is failing to process your yellow bile acids. I hadn’t had a liver patient yet, and figured it was a good chance to learn something new.

The Boston was in A ward, the ward for sick animals. (Healthy animals who are in for elective surgery and the like end up in B ward. Animals on the other end of the spectrum go into the intensive care unit.) I read her chart. She had come in to the ER the previous morning for lethargy, not eating, and not acting like herself. No blood work had come back from the lab yet. The ER had ultrasounded her abdomen and seen no free fluid in there, which suggested that any liver disease was not far advanced. They had heard a heart murmur, and she had looked yellow to them.

I did my own physical exam. Yellow: hmmm. Maybe I could see that her inner lips looked a little yellow. Maybe not. I chalked this up to my inexperience and wrote “mild jaundice” on the physical exam form. Heart murmur: hmmm. Maybe I could hear it, maybe not. It was a little hard to hear over the sound of her breathing. I thought I could hear some swish to her heart, though. Come to think of it, her breathing was awfully loud. Now, Boston terriers have very flat faces, which makes breathing difficult for them at the best of times. But looking at the depth of her breathing, I thought I saw “increased respiratory effort.” It isn’t something you’d necessarily expect in a liver patient, but I wrote it on the physical exam form with a question mark after it.

The resident on the case, Dr. Crow, took a look at the Boston next. “Did you appreciate jaundice?” he asked. I hemmed and hawed. “Maybe she’s a little jaundiced... I’m not sure,” he said. Oh. Um, good. “Did you actually hear her heart murmur, or just write it down because the ER heard it?” I said I sort of thought I heard it but it was difficult. He nodded. “I’m not really sure I hear it either,” he said. Emboldened, I asked about her respiratory effort. “Yes,” he said matter of factly, “that’s elevated respiratory effort.” I was unsure whether to feel good that I’d noticed, or bad that there had been any question in my mind.

We talked about why a dog with liver disease might have trouble breathing. Dr. Crow walked me through the idea that since the liver is involved in clotting, the dog might have thrown a blood clot into her lungs. We sent her off for x-rays of her lungs. While she was gone, her blood work came back: all of her liver enzymes were significantly elevated. This happens when the liver is so unhappy that it starts to leak enzymes, and when the bile backs up because the liver isn’t processing it properly.

When the Boston came back from radiology, Dr. Crow asked me, “So what do you think about her radiographs?” Her lungs looked terrible. She was having even more trouble breathing, so we put her in an oxygen cage. Dr. Crow called an emergency and clinical care faculty member over to talk through the case. The problems with her lungs were spread too far for him to still suspect one clot. We had submitted a request for clotting tests, but weren’t going to hear back for several hours, as it was a weekend. Dr. Crow and the faculty member decided to do a quick ultrasound of the Boston’s heart. Heart failure can also cause fluid to get into your lungs and make it hard to breathe.

We took the Boston out of her oxygen cage, put her on her side, and put the probe on her chest. And there it was: a big lump on her heart. “Well,” the faculty member said, “I think you just found her problem.” Cancer.

Dr. Crow suspected that the mass was a chemodectoma, a type of cancer to which Boston terriers are particularly prone. However, the cardiology service did a consult on her, and they thought it was more likely to be hemangiosarcoma, because of the speed with which it had appeared and because of its exact location on the heart. Hemangiosarcoma is a very bad diagnosis; animals don’t live very long even if it is excised, and it was going to be impossible to cut it off of this dog’s heart. It is not very responsive to chemotherapy, either.

I asked the cardiology faculty member why he thought the dog’s liver enzymes were elevated. We batted around some ideas, but in the end he shrugged: this was not the dog’s primary problem. And cancer, as the saying goes, can do anything it wants.

The Boston’s owner came in to visit her, and Dr. Crow explained the situation. He said that she was having trouble breathing because fluid (probably blood) from the mass had built up inside her pericardium, the sac around her heart. We could drain that fluid (do a pericardiocentesis) and send her home. If it was actually a chemodectoma, she might do well for a while. If it was hemangiosarcoma, she was likely to have some very serious issues in the next few days.

The owner, after a great deal of soul searching, elected to euthanize the dog. If she had chosen the pericardiocentesis, she would still have had to leave her dog in the hospital for at least 36 hours, to make sure that the pericardium did not fill right back up with blood. If she had then taken the dog home, she would have had to deal with the possibility that the dog would have had little to no time before something else bad happened. Few owners want to deal with the chance of their dog being unable to breathe, and having to rush back in to the hospital with a dog in the car that might go into respiratory arrest. I suspect I would have chosen the same thing.

I learned from this case, as I had from so many others during my medicine rotation, that the one-word summary of an animal’s problem can lead you down the wrong road. And yet every time I am drawn in by the easy answer. I suspect that learning to keep an open mind is part of learning to be a good clinician.

Small Animal Medicine rotation

2011-05-03T12:01:00.000-04:00

I have just surfaced from the three weeks of my Small Animal Medicine rotation, in which I worked with Internal Medicine specialists. This is widely known as the most stressful of the core (required) rotations. I will sort of miss the reactions that I got when I ran into a classmate in the hallway and they asked conversationally, “So what are you on?” When I told them, I got a respectful “Ohhhh.”

I got up at 4 am. It takes me an hour and a half to get out of the house now that I have the high energy puppy to exercise in the mornings; I had to do this with a flashlight so that I could see the ball when she retrieved it. I arrived on campus around 6 am, just as the sun was coming up. Before 8 am, I had to do physical exams on all my patients, do their morning treatments, review their test results from the previous day, and write up my assessment of their status, my list of their problems from most to least important, and my plan for them for the day. This was a long process, but got faster as time went on. For the first few days, I was completely flummoxed by things like how to unhook a dog from its IV fluids so that I could take it outside to pee.

From 8-9 am we had topic rounds, in which a clinician would talk us through some topic — feline lower urinary tract disease, common vaccinations and parasites, kidney disease, and so on. After that, we rounded on our patients. I had to stand in front of the cage of each of my patients and try to sound intelligent about what was going on with them. Inevitably I ended up feeling like an idiot, but so did all my rotation mates, so I don’t think I did exceptionally badly.

After rounds, we did whatever our patients needed that day. They had x-rays, ultrasounds, cardiology consults, got scoped to see what sorts of things were up their noses or in their intestines, etc. I did not get to do as many procedures as I wanted, but I did get to perform an abdominocentesis: putting a needle in an abdomen to draw out all the fluid that was in there (and should not have been). I pulled out 800mL of fluid from that cat, and there seemed to be quite a bit left when I was done. These tended to be very sick animals, animals that got referred to our specialty hospital when general practice veterinarians didn’t feel comfortable handling the case (for lack of specialty training, or because they did not have 24-hour care facilities).

In the afternoons, we saw appointments. I did the initial physical exam and took the patient’s history, then put together my problem list and treatment plan, and reported to the veterinarian on the case. The vet then went in to see the animal, did their own physical, and told the owner what was actually going to happen (which sometimes had some overlap with my suggestions).

Several of my patients died — the ones that were diagnosed with large tumors. Several did very well — the chronic kidney disease patients who needed rehydration and supportive care. I was lucky not to lose a patient that I had cared for for longer than a day. I saw a surgery student crying in the hallway after her patient, who had been in the hospital for two weeks, arrested in the ICU and could not be brought back after ten minutes of resuscitation attempts.

I was often at the hospital until 6 pm (a 12 hour day). I had several 14 hour days, and one very memorable 8.5 hour day (on which there was much celebration). The hospital was slow during those weeks, so I did not have to experience the usual regular 15 hour days that most students deal with on this rotation. I only had 2-3 patients at a time; many students had to deal with many more than that. I did work most weekend days, but had one day completely free (I slept for 12 hours) and another day in which I had to go in at 6 am, but discovered there were no patients for me, and got to go back home (and back to bed for 4 hours).

I am still tired today. I am now on a writing week, writing up some of my Master’s research to submit for publication. It is exceptionally pleasant to sit on my couch with the windows open and the spring air blowing in, writing. One of my rotation mates said to me dubiously, “A writing week... Um, you like that stuff, right?”

Yes. I like that stuff.

Links post

2011-03-30T12:37:00.000-04:00

As usual, may of these are old, because I don’t have time to keep up to date on my blog reading.

Dog Fear Isn’t Funny or Cute (Champion of my Heart): Nice analysis of dog behavior seen in the recent viral dog video of the “guilty dog.” In short, don’t treat your dog like that.
“We don't want a bunch of scientists telling us what to do” (Pedigree Dogs Exposed). Blog post from my new favorite blog about dog breeder resistance to scientist input on breeding strategies for purebred dogs. Dog breeding ethics!
The Lady and the Trump—without hungry puppies: The science of stray dog sterilization (Cynthia Mills on the Scientific American guest blog)
Yes! We have no bananas (Border Wars): Inbreeding in dogs and bananas
Web breaks echo-chambers, or, ‘Echo-chamber’ is just a derogatory term for ‘community’ – my remarks at #AAASmtg (Blog Around the Clock)
Bristol University vet students use new “cow machine” (BBC News): Two words: RECTAL SIMULATOR. Seriously, though, this would have been really useful when I was learning to rectal a cow. I love learning tools like this; they let you get the hang of a procedure without causing discomfort to an animal.

The Dairy Welfare Farm Tour, part 2: growing calves

2011-03-29T20:29:00.000-04:00

(Continued from The Dairy Welfare Farm Tour, part 1.)

We pulled up at the farm where Dr. Mulain performs a weekly herd check every Tuesday morning, checking a bunch of potentially pregnant cows to determine if they are in fact knocked up. Lots of rectals! While we were sticking our arms inside of cows, Dr. Mulain pointed out that we can tell a lot about how cows are handled by how they respond to us. When you are in the middle of a herd of cows, do they panic and run away? They have probably not had great experiences with humans in the past. Do they come up to you, sniff you, lick you, follow you around, and generally make pains of themselves? It is likely they have had good experiences with humans in the past. These cows were like mosquitoes; I was literally batting them away. When I yelled “Shoo!” and waved my arms at them, they stared at me blankly. They had clearly been handled gently by the farm workers.

After the herd check was over, we visited the calves in their hutches. This farm used the conventional method of raising calves: separate them from their mothers immediately and raise them in tiny hutches that look like plastic igloos. The hutches are typically clustered together in a little village, but must be far enough apart that the calves can't touch each other. Calves typically live in individual hutches like this from birth until shortly after weaning.

Although the little village of hutches is adorable, something in me rebels at the idea of raising social animals in isolation like this, where they cannot touch another member of their species. Why do we do it? We raise them separately to keep them cleaner. Calves inevitably have diarrhea, and if you raise them together, that will be the method of transmission of all sorts of (sometimes fatal) diseases. So it is safer for them to keep them separate until their immune systems mature. Also, taking them away from their mothers leaves more milk for sale (they are most often raised on milk replacer, which costs less than the real stuff).

This method of raising calves is the conventionally accepted one in the industry, and is what we were taught about in our large animal medicine class. But Dr. Mulain told us about a new method that some farmers are trying, and took us to see it in practice on other farms. You can apparently raise healthy calves in groups if you free feed them, in other words, let them consume as much milk, or replacer, as they want. With the extra nutrition, their immune systems are more robust. The calves grow faster, too.

Dr. Mulain said wryly, “Remember, this isn't abnormally fast growth. This is normal growth.” His perspective is that the dairy industry has been feeding calves smaller amounts to cut costs, but this has resulted in weakened immune systems and smaller calves. With time, we have come to see these weakened immune systems as normal, but they are not.

We saw one farm in which calves had access to a big bucket of milk replacer. They were living in a group of just a few calves. Another farm had turned about ten calves in with three lactating cows. Cows chosen for nanny duty were the low producing cows — the ones later in their lactation cycles who produce less milk. It is amazing that we have bred cows to produce so much milk that a low producing cow can easily support three calves! The calves didn’t bond with a particular cow, but just partook of the nearest milk bar. Because these were low producing cows, they were by definition late in their lactation cycle, so it is unlikely that any of the calves were actually theirs.

This approach to raising calves feels emotionally better to me. I don’t like to see babies of social species raised out of physical contact with other social animals. So the approach to raising calves in groups is appealing. Time will tell if it works well, producing healthy calves and saving farmers money.

Why do veterinarians call them “necropsies”?

2011-03-26T11:14:00.000-04:00

When you dissect a human cadaver to investigate the cause of death, you are performing an autopsy. But when you dissect a non-human cadaver to investigate the cause of death, you are performing a necropsy. Why are the terms different?

I’ve always wondered this but never took the time to find out. (Look, I learn 98,347,824 new things every day in vet school. There isn’t room in my head for more.) But you guys wanted to know, so I embarked on some investigation.

Wikipedia doesn’t have an answer. (Wikipedia, you have been disappointing me lately!) Random googling did get me an answer, at myPetsDoctor.com, where a veterinarian gives us some definitions. According to this site, the common root of both words is the Greek opsis, or to see. Auto means self, and nekro means corpse. So autopsy means “to see with one’s own eyes,” and necropsy means “to see a corpse.” Under this interpretation, necropsy is just a more specific term, and may be used by veterinarians to differentiate the practice of examination of an animal cadaver from the practice of examination of a human cadaver.

Then I asked some of my rotation mates. They opined that autopsy means not “to see with one’s own eyes,” but “to see one’s self,” in other words, to investigate something which is the same as you — a member of your own species. Under this interpretation, necropsy (seeing a corpse) is more general than autopsy, rather than the other way around.

I also asked The Boy for his assistance. He is usually excellent at finding histories of word usage. His sources failed him this time, though.

What I did not do was ask veterinary faculty. I didn’t get a chance to do so yesterday, and anyways in my experience they don’t tend to be very word-oriented people. One exception to this rule was my favorite pathologist faculty member, who unfortunately is no longer working at my school. Dr. Simmons would rant during lecture about how silly some of the veterinary-specific terminology is. I remember him being particularly amused by the insistence of veterinarians on using the term adhese instead of the more generally used adhere (as in, “the two organs have adhesed,” when you mean that they are unfortunately stuck together in one spot). He also gave a brief lecture about the use of dirigibles during World War II when he was supposed to be telling us about the pancreas, which was so interesting and hilarious that I copied it into my notes word for word. He is missed.

So in the end, I still don’t have much more than conjecture about why veterinarians do necropsies while doctors do autopsies. I confess to liking my rotation mates’ explanation better than the one I found on the web, but I am still curious as to when the two terms divided, and if there was an inciting cause for the division. If you know, tell us!

A week in the life: pathology rotation

2011-03-24T21:14:00.000-04:00

I am in my first week (of three) of my pathology rotation. This is known as the laid back rotation: only 8am to 5pm five days a week, with some on-call time. Mornings are clinical pathology. We read slides, learn to make blood smears, discuss lab test result interpretation. At least so far, none of these have been real cases, but it has been interesting, and I’ve learned a lot.

Afternoons are anatomic pathology. We are learning to do necropsies, on real patients when they are available. So far I have seen: a massive hemangiosarcoma tumor on a dog’s heart; a kidney completely lost inside a mass half a foot long (probably also hemangiosarcoma); a pacemaker inside a dog (not the cause of death, but very cool — and before you ask, it was indeed in the heart, not, say, inside the stomach); several yards of horse intestine that was dead due to a strangulating tumor that had cut off blood supply to it. I have a guilty feeling that I should be enjoying this part of the rotation more, but I am having trouble getting past being disturbed by the necropsies themselves.

The Dairy Welfare Farm Tour, part 1: humane handling certification

2011-03-15T21:10:00.000-04:00

I woke up at 6 am, and it felt luxuriously late after my 5:30 am wake up the previous morning. This was the morning of the second of my two electives during third year elective week. The day before I had spent the day in a small animal emergency room. Today, I would ride with a cow vet and some other students, seeing different farms and comparing how they care for their cows. It was chilly, but warmer than it had been, and the weather site I checked suggested a warm afternoon. I dithered between my insulated coveralls and the regular ones, before opting for the regular ones.

Two other students met me at my house, and we made the hour’s drive to the Ambulatory clinic together, where we met the fourth member of our little group. At the clinic, we hovered somewhat aimlessly in the break room and made small talk with the fourth year students there who were on a week of Ambulatory rotation. After a few minutes, Dr. Maolain, who was running the farm tour, walked through and asked us if we all had our boots. We were scornful. Did he really think we would have shown up for a day on farm without boots? (The boots are of course much appreciated when you are walking through a soup of cow manure. They are also more scrubbable than street shoes — easier to hose off and soap before leaving a farm, so that you do not carry infectious disease to the next farm you visit.)

We piled into Dr. Maolain’s truck, a tight fit, and headed out. We had a forty minute drive to our first stop, during which time Dr. Maolain taught us, via a mixture of the Socratic method and long rambles, about the state of third party certification for humane handling of dairy cows.
I have written about this before, but here is the situation in a nutshell: consumers want to buy milk from producers who treat their cows well. Some consumers purchase organic milk for this reason. However, organic certification in no way guarantees cow welfare. Currently, the only way to be sure you’re supporting a producer who treats his cows well is to buy the milk directly from an individual farmer whose practices you know. This is impractical, to say the least, especially for the average consumer who may not know enough about dairy practices to be able to identify those which result in good cow welfare.

One solution to this problem could be third party certification. An organization like American Humane offers certification to farmers for a fee. Consumers then buy milk from producers who are certified by this third party.

Unfortunately, this doesn’t work either! There is no system in place to allow individual producers to have their milk pasteurized and marketed separately. The milk truck collects milk from multiple farms before delivery to the processing plant: if one farmer is certified and another is not, the milk nevertheless mixes together on the truck and in the plant. There is no way to process certified milk separately so that it can be marketed separately.

What’s the solution to that? More processing plants? Maybe, but they are expensive to build, and I don’t know all the relevant issues involved in their funding and construction. It is an interesting problem. I know the public has an interest in milk from humanely raised cows, and it frustrates me that the market systems are not in place to deliver it to them.

(More to come...)

Living with a shy dog: clicking with Jenny

2011-02-21T08:25:00.000-05:00

I am clicking everything with Jenny now! The click marks the behavior which I want to reward. If I just toss her a treat when she does something I want to reinforce, she has a harder time knowing exactly what she did right. Of course, I could mark the behavior verbally (when I don’t have the clicker on me I will say “yes”), but research has shown that animals learn faster with a clicker, perhaps because it takes less mental processing.

The click is obviously not rewarding itself; it is rewarding because it is always followed by a treat, so that she has a strong association between the click and food. The rule is that you must always reward after clicking. If you click the wrong thing by mistake, tough; you still have to reward. With Jack, who is more savvy at this game, I sometimes reward by throwing his favorite toy for him.

What am I clicking Jenny for?

Coming into the kitchen while I am making food
Touching my hand with her nose while I am holding out her harness open as if to put it over her head
The Boy clicks her for responding to him saying her name. Because he is a martial arts instructor, he has a very good sense of how to reward small progressions in physical responses, so he is clicking just as she starts to sit up in response to him.
Eye contact with me when scary things happen

Jenny on her second day with me

Jenny today: “Why did you put the clicker away? I was having fun.”

Go go clicker training!

What vet students talk about with their boyfriends

2011-02-17T09:21:00.000-05:00

Me: So I’m trying to schedule this dairy farm welfare elective, but the day all the interested students are free to do it, the faculty member has a herd check scheduled. He thinks it will be fine, we can use the herd check as a starting point, but you know how these things go.

The Boy: No. What’s a herd check?

Me: Rectalling a hundred cows to tell if they are pregnant.

The boy makes a face.

Me: It’s not so bad, it’s just kind of boring, and I’ll be doing plenty of that on my Ambulatory rotation, I don’t need to be doing it during my elective week.

The Boy: So all the cows get bred at once, that’s why you do a hundred?

Me: Well, it depends on how you run your farm, but no, for this particular farm, Dr. Maolain visits them every week. So he’s checking a hundred cows a week. Well, I don’t know that it’s a hundred, actually.

The Boy: So he’s checking all the cows?

Me: Just the ones who were bred recently. Actually, knowing when to breed them is a whole Thing. They come into heat every 21 days, but they are only in heat for less than a day. The best way to know when to inseminate them (which almost everyone does artificially) is to watch them to see when they are in heat. But it is a real pain to watch all your cows all the time. So you can also use hormones to sync them, and to narrow the window for when they will come into heat.

The Boy: How long after you breed them can you tell that they are pregnant?

Me: That was a test question. It was a lot of tests ago, though. I don’t remember.

But I have looked it up for you (and as a review for me). There are four positive signs of pregnancy in a cow that you can feel per rectum: fetal membrane slip (day 30), the amniotic vesicle (day 30), placentomes (day 75), and the fetus (starts at day 65, but by mid-gestation may be too deep in the abdomen to reach with your arm). If you can feel at least one, you can say that the cow is pregnant. The fetal membrane slip is supposed to feel like the seam on womens’ stockings; it is the allantois inside the uterus. The amniotic vesicle is the sac enclosing the fetus (and it is apparently not recommended for veterinary students to go poking at it, but people who know what they are doing are OK).

Placentomes are where the cow uterus connects to the placenta, and there is seriously not a Wikipedia article on it for me to point you at! Bizarre. Different kinds of animals have different ways of getting nutrients from the mom to the baby during pregnancy, and that is why cows have placentomes and we don’t. (If you want to know more about that, comment! I might could write a post on it.)

Euthanasia Day

2011-02-13T10:15:00.000-05:00

Euthanasia is so depressing that at my school, they just teach you about it all in one day to separate it from the rest of the curriculum. Apparently it was originally students who came up with the idea for Euthanasia Day; the curriculum at the time did not directly address these issues. Students organized and ran the first several euthanasia symposiums before the school subsumed it into the core curriculum as a requirement. There will be no tests on what we learned on Euthanasia Day, but attendance was taken.

We started the day with the definition of euthanasia, according to the Animal Welfare Act: “the humane destruction of an animal accomplished by a method that produces rapid unconsciousness and subsequent death without evidence of pain or distress, or a method that utilizes anesthesia produced by an agent that causes painless loss of consciousness and subsequent death.” I wish that we had addressed the current debate about use of the term “euthanasia” for anything other than the destruction of an animal for relief of pain or discomfort. I try to refer to “sacrifice” when I am talking about the destruction of research animals in pursuit of research, and “slaughter” when I am talking about the destruction of food animals for food. I have read a book by a dog trainer in which she insists that destruction of a dog for aggression should be called “execution,” which I think is an interesting argument but an awfully charged choice of word.

Next up was the pharmacology of euthanasia: which drugs to use and how. We covered the debate about human execution by lethal injection as it related to veterinary medicine: the AVMA’s euthanasia guidelines have been used in court cases about lethal injection, to the extent that the AVMA chose to edit its guidelines to point out that they were intended for discussion of animal euthanasia only and not human execution. The issue seems to be the difference between mixing three drugs, including a sedative and a paralytic, in one syringe, which the AVMA finds unacceptable for animal euthanasia (what if the paralytic took effect before the sedative? That would not be humane), and the triple injection used in humans, which uses similar drugs. In humans, the three injections are given separately, so there is no chance of the paralytic taking effect before the sedative. However, the AVMA statement that this particular approach is not humane has been taken out of context.

Then we covered the issues in euthanasia in various species.

Horses: It is alarming when they go down! They are big animals, have a long way to fall, and do not often do so gracefully. Do you want the owner to be present for that? Secondly, what do you do with the body? It takes a backhoe to bury it. There are disposal options, but they are expensive and limited. My school lives in fear that the single disposal option available to us will disappear if that company goes out of business.

Wildlife: If you find an injured wild animal on the side of the road, do you bring it in to the clinic knowing that it is too badly injured and will be euthanized there? Is it better to leave it, so as to avoid the stress of being handled by humans? (The veterinarian mentioned all the things you might want to take into account, such as, predators probably won’t come finish it off until evening, so what time of day is it?) We also discussed the emotional difficulty of being a wildlife veterinarian and having to euthanize a wild bird for a damaged wing. If the wing can’t be repaired, the bird can’t be released, even if saving the bird’s life would be easy. Some birds can be placed in educational facilities, but no educational facility is interested in a red tailed hawk, an incredibly common species in this area which makes up the bulk of the birds coming in to our wildlilfe clinic.

Exotics: I almost hesitate to relay this tidbit, as I feel like I must remember it incorrectly. We were told about research in which brain activity was measured in turtles up to 72 hours after decapitation. (Did I remember the number wrong? But you know, even one hour would be pretty incredible.) So how do you humanely euthanize a turtle? Another issue is their extremely slow respiration rate, so that euthanasia in a gas chamber takes a long time too.

Cows: We got to see a video of a cow dying by gunshot and another of a cow dying by injection. Both appeared extremely quick to me. Farmers do often choose the gunshot route, because they like to dispose of the cow’s body under the manure pile. It is obviously not a good idea to have a carcass full of euthanasia medication on your farm: one of our faculty members says that he had to return to one farm after injection euthanasia of a cow to treat the farmer’s dog for pentobarbitol toxicity.

We also had a talk by a certified animal grief counselor. She asked us to do a little role playing. Now, I have been in role playing games for fun and profit (okay, not the profit part), and I had some issues with how poorly structured this role playing was. This has been a recurring issue for me in vet school. I should start a gaming group for faculty.

Finally, we had a panel discussion with local small animal practitioners, which was completely open ended: we just asked questions. As we were wrapping up for the day, the final question was “Can you tell us about the best euthanasia experience you had?” The practitioners sort of looked at each other blankly. Then one volunteered, “I have an experience to tell you about.” She relayed the story of the euthanasia of a long-term patient, an older dog whom she had treated for years. She got a little smile when she said his name; she was clearly very fond of this dog. The owner chose not to be in the room, so it was just her and her tech. They injected the solution and the dog relaxed and was gone. They waited to see if his body would have any last reflexes; sometimes you see a last gasp for breath after the animal is already really dead. And what they saw was a tail wag, a thump thump thump in the same rhythm, she said, as when you come into the room and your old dog greets you. The tech said in amazement, “Did you see that?” And the vet replied, “I think he likes where he’s going.” It was the perfect end to an interesting but emotionally difficult day.

Living with a shy dog: target training with Jenny

2011-02-10T19:28:00.000-05:00

When last I reported on the state of my shy dog Jenny, she was submissively urinating every time I went to put a leash on her. We nicely solved that problem when she volunteered to go outside and come back inside on her own and no longer required a leash. She is extremely responsive to my indications about what it is time for dogs to do next, and the elder dog in the household helps instruct her as well. So while I have continued to desensitize her reactions to the leash (by showing her leashlike things and then giving her treats), I have been focusing on other things with her lately. This is my greatest failing as a trainer: I get bored with one program and move on to the next.

These days, Jenny and I are working on target training. The idea is to train the dog to touch a particular object on command, commonly a yogurt container top, which is what I’m using. Target training is useful as a stepping stone for training more complex behaviors. You can use it, for example, to train a dog to close a door on command, by taping the target to the door and then eventually removing it. In this case, I am hoping to use it to encourage Jenny to touch me more, by giving her a way to touch me that is under her control (touching a target in my hand). Of course, we are starting out with the target on the couch next to her, where she feels safest.

The work I was doing with her before was classical conditioning, which is used to change the way an animal feels about something. I was pairing something good (food) with something that I wanted Jenny to feel good about too (the leash). In the case of target training, I am using operant conditioning. The goal here is not to change how Jenny feels about the target (who cares if she likes a yogurt top or not?) but to change her behavior around it (show her that it is useful to touch it with her nose, eventually on command).

Specifically, I am using a clicker for this purpose. I’m not going to explain clicker training in this post, but if you are interested in clicker training with behaviorally challenging dogs, Click to Calm is highly recommended.

So, Jenny is doing great. We’ve had four sessions so far. Session one: I tossed the lid in front of her repeatedly and rewarded her for sniffing it. Then I stopped tossing it, and rewarded her just for looking at it. She sniffed at it again once more before the end of the session (jackpot! Ten treats in a row and end on a high note!).

Session two: I only tossed the lid down once or twice to get her started. I still rewarded her just for looking at it. This time she showed more intention in her sniffing at it, like she was thinking about what she was doing, and she sniffed at it three times.

Session three: I only tossed the lid down once. She sniffed it repeatedly, immediately after each treat (whereupon, obviously, I gave her another treat). When it was clear that this was easy for her, I moved the lid a half inch farther away. This flummoxed her a little, possibly partly because I had moved the lid, which might have suggested to her that I didn’t want her to interact with it. So I went back to rewarding her for looking at it. By the end of the session she was sniffing it again, though not quite as regularly. Good thing I only moved it a tiny amount; she was clearly not ready for more.

Session four: she was nosing the lid so regularly that I started inching it farther away from her every few repetitions. She followed, but on the third or fourth time I moved it away, picked it up in her mouth and moved it back closer to her. Jackpot! (Lots of treats for that, all in a row.) That wasn’t what I had originally intended her to do, but I figure it’s a good idea to reward her for being assertive and really interacting with her environment.

Target training with her has been fun. She is extremely smart, much more limited by her shyness than by her brains, sort of the opposite of working with my other dog Jack, who is very outgoing but of only average intelligence. I think the signs are good that the target training work will be useful in bringing her out of her shell.

Cow anesthesia

2011-02-02T09:24:00.000-05:00

Instead of blogging, I have been shovelling snow. And sleeping off being sick. Also maybe there was some studying in there too. But I am rallying! I love New England winter! Especially when school keeps getting closed down for snow days!

Last week I had my bovine anesthesia lab. When I learned to do anesthesia on a dog, it was a precise and complicated process which took place in a hospital. The dog got pre-anesthesia medication, had a tube down her throat to help her breathe, and got post-surgical pain meds. The process is very different with a cow.

With cows, mostly you do standing surgery — surgery while the cow is awake, with local anesthesia so they don’t feel the pain. Why? Obviously, part of the reasoning is financial; farmers cannot afford to take their cows in to the hospital for surgery, and the equipment for general anesthesia is not available on the farm.

However, even if you can afford to put a cow under general anesthesia, it might not be the best thing for the cow. Putting a tube down the throat of any ruminant is somewhat more dangerous than with a dog. Ruminants are more likely to aspirate their stomach contents and get aspiration pneumonia, which is definitely something you want to avoid. More importantly, cows have these huge stomachs. The compartment called the rumen is particularly enormous, containing around 25 gallons of material. This is where all that grass (or, in today’s world, corn) marinates in a soup of saliva and bacteria, and the bacteria generate energy which the cow uses. Putting a cow on her side means that the huge rumen is lying on abdominal organs. It can make breathing very difficult.

So in bovine anesthesia lab, I injected lidocaine along specific nerves in order to block areas of the cow’s side. I have not yet seen standing surgery in a cow, but when I do, I will let you know what it is like. Reaching inside a standing animal to move things around and sew things up will definitely be an interesting thing to see.

Links post

2011-01-14T17:03:00.001-05:00

Science Online 2011 is this weekend and I really wish I could be there. Luckily I can attend virtually.
A post from this blog will be included in the 2010 Open Laboratory!

Would you cut off your dog’s leg?

2011-01-08T10:28:00.000-05:00

Yesterday we had a lecture on osteosarcoma, a cancer of the bone. Osteosarcoma is not a good cancer, guys. It is liable to occur in younger dogs, it is extremely painful, and no matter what you do, it is almost certainly going to come back.

But there are things you can do to reduce or remove your dog’s pain, and to get more time with him (as much as a few years, sometimes). Because this tumor is so painful and aggressive, you really want to cut it out. But that is awfully hard to do as it usually appears in the long bones of the leg. So the surgical answer is almost always amputation of the limb. Alternatively, you could just do a course of chemotherapy to knock it back for a while, and deal with the pain using analgesics.

Who would want to cut off their dog’s leg? Chemo + painkillers is the obvious answer, right? And yet it is not. Chemo is much less effective than surgery, so you will have less time with your dog if you choose this option. And oral painkillers just don’t seem to help very much with this tumor, so your dog’s quality of life is likely to be pretty poor during that remaining time.

Amputation is actually a pretty good option. It just removes all the pain. And dogs do great with three legs. Dr. Glace said, with his typical deadpan delivery, “Some people say it’s like they don’t know they have lost a leg. That’s stupid. Dogs aren’t that dumb. They know they’ve lost a leg.” But they don’t care about it the way we do. They relearn to walk and then they do fine. Three legs is still one more than most of you have. I have seen three-legged dogs (“tripods”) in a flat-out run. No problems.

Dr. Glace says he won’t amputate a leg from one of the truly giant-size breeds (Great Pyrenees, Saint Bernard, Newfoundland), but noted that he amputated a leg from a mastiff (those are very big dogs!) a few months ago and the dog did extremely well. To test if the dog would manage successfully on only three legs, he employed the high tech test of picking up one leg and making the dog walk around the room on the remaining ones. Success.

The biggest problem, Dr. Glace says, is that owners really don’t want to amputate their dog’s leg. There is something viscerally upsetting about it. It’s one of those situations where your instincts might lead you wrong, leaving your dog with less time to live and more pain. Personally, I can report that I saw a tripod running an agility course, and she did just fine, even over the jumps. I direct you to this blog post about Serena, an agility tripod. Go tripods!

Everything I touch is missing a uterus, or, What is a freemartin?

2011-01-06T08:53:00.000-05:00

Bovine procedures lab today and yesterday! (Why do they schedule these outdoor labs for the middle of the winter? Thank god for my insulated coveralls, three shirts + sweatshirt, and leggings.)

Bovine procedures lab involves actually doing lots of procedures on year-old Holstein heifers. These heifers (young cows who have not yet calved) are owned by an area farmer and lent to my school for a year or so, during which time the farmer pays for their upkeep and we get to do procedures on them. There are lots of rules about how many procedures can be done on an individual cow per day, to make sure they don’t have to put up with lots of invasive procedures (but even so my group frequently took breaks to let our heifer rest). The procedures included things like insertion of IV catheters, insertion of a stomach tube, haltering, tying up a leg, and so on. I do feel a little uncomfortable about the animal use in this lab, but I recognize the practical difficulties of spreading the procedures out over more cows. Also, I figure that once I am an all-powerful school administrator, I can find a creative solution to the problem.

These are super friendly heifers! I was surprised. One of them followed us around and solicited neck rubs. They are still pretty small, weighing in at around 700 lbs (which nevertheless felt like a lot when ours stepped on my foot).

Scratch my neck, bitches!

Late in the second day we got ready to do our vaginal exam. LPK lubed up the speculum but good and started to work it in. No go. It just wouldn’t go very deep. We called over Dr. Cole, who tried it himself, failed, said hmmm, put on a long glove (up to the shoulder), lubed it up, and did a rectal palpation. You do a rectal palpation as another method of evaluating the reproductive organs; you want to feel the cervix, uterus, and ovaries. This can tell you what stage of her cycle the cow is in (did she ovulate? is she perhaps even knocked up?). He took his arm out, looked at me, and said, “Give it a shot and tell me what you feel.”

Ah, my first bovine rectal palpation. On with the super long glove and lube. Brrr — you have to take off your insulated coverall top to do this and roll up your sleeves so your arm is bare to the shoulder; luckily it is warm inside the cow.

I got in and felt around. Lots of poop! (You have to sort of shovel that out at first. Dr. Cole had gotten most of it but I cleared out a little more. It is not cool to mistake a handful of poop for an organ.) I felt a cervix, but it was awfully tiny. And... nothing else. No uterus, no ovaries. This didn’t necessarily mean a lot, since I don’t really know what I am doing, but when I reported my findings to Dr. Cole, he replied, “That’s exactly right. She’s a freemartin.”

What’s a freemartin? This is a fairly rare condition. It happens when there are twin calves, one male and one female. The female is genetically normal, but as she is awash in a sea of testosterone in utero, she develops abnormally, into an intersex animal. I don’t know if all freemartins develop exactly the same way, but this one was typical in her lack of uterus and ovaries. Her vagina was a short, blind sac, which is why we could not get the speculum in.

It is freakish, I tell you. My first spay dog had no uterus, and now my first bovine rectal palpation doesn’t either. What are the chances? Am I cursed?

Living with a shy dog

2011-01-01T18:08:00.000-05:00

I adopted a shy dog two days ago. You can see how tense she is in my house in the first picture. I’m including a second picture to prove that she isn’t like that all the time! (Also: doesn’t she look just like a domesticated fox that was dipped in yellow paint?)

This is Jenny. Jenny spent her first ten months on the same property on which she was born. She got to live with other dogs and knows a lot about how to interact with them. However, she doesn’t know a whole lot about interacting with humans, and we are pretty scary to her. She also doesn’t have much experience with the world in general. She’s been with me for about two days now and is just getting to the point where she’s willing to eat while I am in the room.

When Jenny is really alarmed by something I do, she pees. This is known as submissive urination; she’s sending a social cue to say “I’m harmless; please don’t eat me!” I can mostly avoid doing things to her that are this scary, but sometimes I do have to put a leash on her to get her outside, and then she is liable to pee. I’m taking various management measures to preserve my furniture, but this afternoon Jenny started being interested in eating treats that I tossed her, so I saw the opportunity to engage in some counter-conditioning with her.

The problem

When I approach Jenny purposefully and pull out a leash, she is scared, and pees.

Conditioning a new emotional response

The goal is for Jenny to see the cue (my purposeful approach, leash in hand) and feel good about it instead of scared. The solution is to break the scary cue down into cues that are smaller and less scary, and help her work through each of those with the help of something positive (treats).

It’s not just one thing that tells Jenny that I am about to grope around for the clip on her harness and attach a leash. It is my approach; the way I look straight at her; the purposeful way I walk towards her; the display of the leash in my hand. Each of these things is really a separate cue, and each should be worked on individually.

Working with Jenny

Jenny was on the couch downstairs. I wanted to be able to walk down the stairs and approach her with the leash. First, I tried it without the leash. I walked down the stairs more slowly than usual, stopped farther from her than usual, and avoided eye contact. I tossed her a treat. She thought about it, then ate it.

I repeated exactly the same sequence of events. This time, she ate the treat promptly, suggesting that she was comfortable with the sequence.

I tried it again, and this time walked a little bit closer to her. That was okay. I tried again, making eye contact and walking faster. This scared her; she wriggled away from me on the couch. I stopped and backed up, looked away, threw a treat. She waited for me to go upstairs before she ate it. I tried again, this time backing up to something that she had previously accepted — stopping a ways from the couch and not making eye contact. This was still successful (she ate the treat without appearing alarmed). Phew. I started progressing again, but more slowly.

Counter-conditioning is extremely simple, but it can be really hard to implement properly in practice. We tend to get impatient. Why do we have to take such small steps? Can’t we go faster? Unfortunately, if the protocol you’re trying isn’t working, the answer is almost always to break the sequence you’re conditioning into smaller events and add new challenges more slowly (or maybe give better rewards; I could explore different types of treats to see if there is something more exciting for Jenny). But that is really hard for most humans. That’s the challenge of counter-conditioning and why it is often best to do it with the help of an experienced trainer until you get the hang of it.

Hopefully I will be able to teach Jenny over the next few days that the leash isn’t scary. For tonight, I stopped while I was ahead and didn’t push things too far.

Learning how to tell if a dog is in pain

2010-12-19T09:54:00.000-05:00

I completed my second spay lab, in which third year veterinary students spay a dog from a shelter or low income family. Unlike my first spay lab dog, this dog had a uterus! (In fact, she was in heat, so I was pretty confident ahead of time that she would. My boyfriend: “How can you tell she’s in heat?” Me: “She has a vulva the size of Texas.”)

Linnea was an extremely nice dog who was extremely unhappy about being in the spay clinic for two days. She pawed at the cage door so much the first night that we gave her a sedative to take the edge off. Her spay went well, but when it is only your second spay, you still don’t trust that you haven’t done something stupid and that the dog isn’t in real trouble. (One of my classmates reports that she actually went to visit her spay patient at the shelter several days later, to make sure she was okay. My classmate pretended to be interested in adopting the dog in order to get time alone with her, so she could look at her spay scar.) So when Linnea started making a lot of noise the evening after her surgery, I was very anxious.

First I asked the anesthesia technician if he thought she needed more pain medication. He pointed out that she had been a very vocal dog before the surgery, and was almost certainly just stressed now, especially due to the after- effects of all the other medications we had given her making her feel less than mentally competent. My spay partner Lily and I looked at Linnea anxiously after letting her out to pee. Lily said: “Well, she seems to be standing sort of hunched over.” I said: “Yes, I really would like to give her more meds!”

The veterinary intern came by around that time, for evening rounds, and I explained how Linnea looked painful to us. (It is veterinary jargon to say an animal is “painful” rather than “in pain,” and I have seen this usage really annoy non-veterinarians. I am not sure why we say it that way, but that is how it is.) Now, Lily and I had recently completed our anesthesia course, which had several lectures about how to tell if dogs are painful, but of course in the heat of the moment we had completely blanked on this. The veterinary intern simply put her hand gently but firmly on Linnea’s spay incision. Linnea didn’t even blink; she didn’t turn her head or growl or flinch. The intern said confidently, “She doesn’t appear to be painful,” and this time, I believed it.

Dogs do sometimes vocalize when they are in pain, but it is not the best way to tell. Many dogs in pain do not vocalize, and there are tricks of body language that you can use to tell what is going on in their heads. We had some fascinating lectures on that, unfortunately far too image-filled for me to reproduce here.

I learned from this experience. When you’re not sure how to proceed, take a deep breath and think back to what you were taught in class. We actually have received a very good foundation for clinical work, but it can be really hard in the moment to pull the appropriate fact out of the mass of information packed into our brains after three years of veterinary school!

How to learn how to do ... lots of procedures

2010-12-05T21:08:00.000-05:00

Recently I had my Small Animal Procedures lab, in which my classmates and I learned how to perform dentistry, take skin biopsy samples, do trans-tracheal aspirates, take bone marrow biopsies, and a raft of other procedures. I wouldn’t feel comfortable doing any of these procedures unsupervised yet, but I did get to actually do them with my own hands rather than just pick “do a trans-tracheal aspirate” as a multiple-choice answer on a test.

In the past I have described learning on shelter animals that need low-cost procedures, or ex-research dogs that are living at the school until they can be rehomed. This lab used the bodies of animals who had been euthanized at our hospital, and whose owners had agreed to allow us to use them. It is always somewhat disturbing to spend several hours with a dead dog, but this is the one use of animals for teaching that I am one hundred percent happy about. Learning on live animals is never perfect, although my school does its best to find constructive ways to obtain animals for us to use. We had to do so many procedures for this lab, and such invasive ones, that it made sense to use cadavers.

The trans-tracheal aspirate is a particularly interesting procedure to do. The idea is that an animal has some sort of infection in its lungs, and you want to know exactly what. So you thread a catheter into its trachea and down into its small lower airways, pump some fluid in, suck the fluid back out, and test it for bacteria. Okay, but if you thread that catheter in through the mouth, it is going to be contaminated with all kinds of bacteria that you’re not actually interested in, right? So how do you get the catheter in to the trachea without getting mouth bugs all over it?

You stick a big needle in through the outside of the dog’s throat directly in to the trachea, and thread the catheter through that. This means when you stick the needle in, you have to know when its point is inside of the trachea. You can’t see where the point of the needle is, obviously, and that’s why it’s a learning experience. This procedure was particularly hard for me. I kept sticking the needle in, being convinced it was in the right place because I felt a “pop” as it passed into the trachea, and then not being able to thread the catheter in. A tech told me patiently, “if the catheter won’t thread, that means it’s not in the trachea.” Goddammit. I tried again. And again. And eventually it worked.

This was a really enjoyable lab. Four of us worked on one dog cadaver. There were also a few cat cadavers for multiple groups to share. It felt good to do some of the procedures we had learned about, but scary to imagine doing them on living patients in the near future.

Veterinary fact of the day: feeding guinea pigs

2010-12-01T18:13:00.000-05:00

We are having some of the final lectures for our zoo medicine course, and today’s was about pet rodents — guinea pigs, rats, chinchillas, mice, and gerbils. Coincidentally, we also covered many of the same animals in our lecture on laboratory animals, earlier in the day. Both lecturers emphasized the fact that guinea pigs require vitamin C supplementation. Unlike most other species, they can’t make it themselves, and if you don’t provide it in their diet, they will get scurvy. Some owners, we were told, are so dedicated in their C supplementation that they actually provide too much, which can also be problematic.

A lot of our zoo medicine course has covered good feeding and management practices. It seems like a large part of practicing on exotic pets (a term which includes things you might not think of as exotic, like rats and rabbits) includes making sure that people are managing their pets right. Basic husbandry is something that is rarely covered in our small animal medicine course, which is about cats and dogs. We assume that people know how to feed them and what temperatures to maintain them at. I think the really good small animal veterinarians, though, are asking their clients about all kinds of management issues and offering advice, not just waiting for a problem to crop up. Maybe vet school should prepare us more for that.

What I’m up to: I am sliding in to the last few weeks of the semester, and don’t have a lot of extra emotional energy for blogging. I miss it and will certainly be writing more when final exams are over. Next week is my second and final spay lab. Wish me luck for getting a dog with a uterus this time!

How to learn how to ultrasound a dog

2010-11-15T18:03:00.000-05:00

I’ve seen a bunch of ultrasound images (still and moving) throughout vet school. Lecturers will flash up a picture and say things like “and that’s what a pyometra looks like on ultrasound.” And what do I see? MASS OF GREY AND BLACK.

[Image source: Imaging 2003;15:72-78.]

Today we had our first lab in which we got to actually handle ultrasound machines. When you’re driving, everything makes a little bit more sense.

The procedure

Take a dog. Sedate it. Put it on its back (padded to stay in place). Slather gel on its belly. Watch as someone who knows what they’re doing shows you how to find the liver, gallbladder, and kidneys with the ultrasound probe.

The liver isn’t so hard: it’s tucked up under the rib cage, so you put your probe at the end of the rib cage, right in the middle of the belly, and look around. The round black circle that is the gallbladder tells you that you’ve found the right spot. The liver is all around the gallbladder, and once you know that, you can see that it is indeed a slightly different color and texture of grey than all the grey around it. Move the probe back and forth along the dog’s belly, following that particular grey texture until it disappears. You have imaged the liver!

The kidneys are a lot harder to find, as they are not so near the surface of the dog’s body, and they don’t have as clear a landmark. When you do find them, they are super cool to look at, though. The liver is a plain mass of grey, but the kidneys have a pattern to them that looks exactly like a kidney looks when you cut it in half in gross anatomy lab. It convinces you that what you’re looking at is for real and not just made-up images on a computer screen.

Try again with the urinary bladder. That’s easy to find, a nice big black circle. You can change its shape by pushing down with the ultrasound probe. As you are being pleased with how easy this is, the radiology resident comes over and asks if you want to try to find the prostate.

The prostate is hard to find, I tell you what. The resident had to find it for me (I held on to the probe while he moved it, so that I could feel where to put it), and when he pointed it out to me, I was like, “That’s a thing? A thing I am supposed to be able to recognize later? It doesn’t look like anything!”

Wipe the gel off the dog. Call someone to give him his reversal agent to counteract the sedative. Wrap him in a warm blanket and cuddle him while he wakes up.

Success! You saw a liver, gallbladder, urinary bladder, and prostate!

The students

There are two labs for the class of 82 students, so this lab had 41 students in it. There were 5-6 students per dog, 6 students in my group; we took turns with the probe. The dogs were sedated for about 80 minutes, which didn’t feel too long to me.

The instructors

The instructors included: a private practice veterinarian; two radiology residents; a representative of the ultrasound equipment company (who may or may not have been a vet, I wasn’t clear, but certainly knew how to ultrasound a dog).

The equipment

A manufacturer of ultrasound equipment lent us the equipment for the day, so that we could have several ultrasound machines in use at once. They did this out of the kindness of their hearts, and perhaps with the idea that we would think well of them and perhaps purchase some of their equipment some day.

The dogs

The dogs came from my school’s teaching colony. These are ex-research dogs. The research laboratories can’t place the dogs directly in homes once their stint as research animals is over, so they give them to my school, which socializes them for a few years and uses them in procedure labs like this one, then adopts them out. They retire to pet homes for the rest of their lives. I also learned how to do a neurology and cardiology exam on these dogs, among other non-invasive procedures.

The dogs represent a complex moral question for me. Is it acceptable to use them like this? They are cared for well, but they live in kennels rather than homes, and they do have procedures like this done on them, which while non-invasive must be at least a little stressful. However, my school is doing a good thing by helping them to transition from a research environment to pet homes. And the alternative would be that I would learn ultrasound techniques on patients, animals who were actually sick, and perhaps less able to tolerate my bumbling around. In the end, I like this solution.

So thank you to the dog who let me practice on him (although it was not his choice). Thank you to the people who taught me. Thank you to the company who lent the equipment. It was a good lab.

Links post

2010-11-14T09:05:00.000-05:00

Scared or feral: How do you know? (Pet Connection)
Repost: The ethics of snail eradication (Adventures in Ethics and Science): “Plenty of people are happy just to get the food without knowing the details of its provenance. I’d rather shoulder the responsibility of doing my own dirty work here. The karmic costs of my food are not hidden out back in the fields behind the farm stand.”
Canine Cogniton and Pointing Gestures – An Update (The Other End of the Leash)
Vaccination, Confirmation Bias, and Knowing Your Audience (The Thoughtful Animal): on effective communication of science
Enrichment in Captive Cephalopods (Cephalove)

More on women in veterinary medicine

2010-11-07T13:46:00.000-05:00

Some while back I wrote a post asking why there are so many more women than men in veterinary medicine. Recently, that post received a comment from Anne Lincoln, whose research into exactly that subject has just been published. Her findings are summarized at Eurekalert. You should read that summary, but in short:

Women now dominate the field of veterinary medicine — the result of a nearly 40-year trend that is likely to repeat itself in the fields of medicine and law...That's the conclusion of a new study that found three factors that appear to be driving the change: the 1972 federal amendment that outlaws discrimination against female students; male applicants to graduate schools who may be deterred by a growing number of women enrolling; and the increasing number of women earning Bachelor's degrees in numbers that far exceed those of male graduates, says sociologist Anne E. Lincoln.

I still have questions! If veterinary medicine, medicine, and law are all changing, why is veterinary medicine changing first? Why are more women earning bachelor’s degrees than men these days? Enquiring minds want to know. Hopefully Dr. Lincoln is continuing research in this area.

I also recently encountered Science IS Sexist, in which Alexandra Jellicoe asks, Do you think that women are more intuitively than logically intelligent and do you think that as scientific research has been designed to only include this logical, evidence based approach, it alienates women? She concludes that the female brain is likely to find the existing scientific research approach dull, dull, dull. It is too narrow and systematic and does not maximise the use of the hive of activity going on in a female brain. Men approach problem-solving from a task-oriented perspective while women typically solve problems more creatively.

What I find particularly interesting about this idea is that my friend LPK and I have observed that in vet school, dominated by women as it is, we tend to have different approaches to problems than most of our classmates. We tend to approach problems more intuitively and creatively; our classmates are more likely to approach problems more systematically. LPK and I also differ from most of our classmates in that we spent significant time out of school, in non-veterinary careers, before entering vet school. (Five years for her, more like 12 for me.)

So is vet school the place for women to go who think like men? Did it take me so long to realize I wanted to become a veterinarian because (in part) I had to overcome the obstacle of having different approaches to problems than the rest of the veterinary community?

Food for thought. I usually like to leave you with an opinion, but I don’t have one here, just questions.

New comments policy

2010-11-02T07:56:00.000-04:00

I just turned on moderation for comments. I hate to do it, but lately I have been getting a lot of spam comments (put in by real people who can pass the spam filter, but with links to commercial pet supply sites — I have heard about this on other dog-related blogs). I will do my best to approve real comments promptly. I know this is inconvenient for all; sorry!

Veterinary fact of the day: is it the brain or the heart?

2010-11-01T20:50:00.001-04:00

This morning as I was walking out the door on the way to Lottery Day, I looked over at my golden retriever Jack and observed that he was having a small seizure. Jack does this from time to time and these days I don’t consider it a big deal (though of course when it first happened it was a very big deal, and I visited several vets about it). I sat with him until it was over, and then he was fine. Dogs are great; I would have been distressed for hours afterwards. (As I headed off to Lottery Day, now slightly late, I thought to myself: “This is the best excuse for being late ever! I should have thought of it years ago.”)

So, you are an emergency veterinarian, and a young woman brings in her newly-adopted golden retriever who, she reports, had a seizure this morning. Do you accept this at face value and explore only things that could be wrong with this dog’s brain? Or might another system be at fault?

In fact, it could be the heart. Some heart problems can cause collapse (“syncope”) which can look very much like a seizure. In both cases, the dog can collapse on its side, lose consciousness, and urinate or defecate. So how do you tell the difference?

Seizures can last several minutes. They usually don’t seem to be triggered by any particular activity, but the dog sometimes seems to be able to predict them (the “pre-ictal period”) and may act differently. During the seizure, the dog is likely to move its limbs in classic “tonic-clonic” motions, drool a lot, and possibly chew on its face (you know how with humans, they warn you to secure the tongue if you have a chance?). Afterwards, recovery can take a few more minutes in which the dog is not quite right (the “post-ictal” period).

In contrast, syncope is shorter, usually more like 30 seconds. It may be associated with exercise or a coughing fit. You are not going to see “tonic-clonic” limb motions during syncope; you are more likely to see the dog go limp. The dog is unlikely to drool or chew on its face. Recovery is a lot faster.

Jack’s seizures are extremely mild; he does not even lose consciousness. (A vet once told me that it can be hard to tell if dogs lose consciousness during a seizure and that I was probably mistaken. I replied that I had once attempted to take Jack’s favorite toy away during one of these episodes, and that he had managed to take it back, even with all his muscles contracted so that he had real trouble moving.) But they are clearly seizures.

So if your dog has a collapsing episode, now you know what to pay attention to so that you can help your vet figure out what’s going on.

What I did today: Lottery day! I got most of what I wanted, but not everything. Now my schedule is set for my core rotations from March 21, 2011 to March 5, 2012. After that I have two months of elective time until graduation (there is also some elective time built in to the preceding year). I have such fun electives planned, you guys! I am really enthusiastic about them. I don’t want to jinx them by reporting them here too early, but I’ll let you know how they go when they happen.

[ETA: A friend comments:

Be careful! You say, “you know how with humans, they warn you to secure the tongue if you have a chance?” This is an old wives’ tale.

“Do not try to stop the seizure. Do not hold or restrain the person, nor put anything in the person’s mouth. Care for a person who has had a seizure the same way you would for an unconscious person. … Do not try to place anything between the person’s teeth. People having seizures rarely bite their tongues or cheeks with enough force to cause significant bleeding. However, some blood may be present.”

— American National Red Cross, First Aid/CPR/AED for Schools and the Community, 3rd ed., 2006; p. 156.

P.S. Everyone should get basic first aid and CPR training…]

Veterinary fact of the day: playing detective with bladder infections

2010-10-31T11:26:00.000-04:00

I’m learning about urinary tract problems at the moment. I love this section, because the guessing game of finding out where the problem is can be so much fun. As a small example: an owner brings in a female dog who has been asking to go outside more often. Recently the dog had an accident in the home and there was blood in the urine. You suspect a urinary tract infection, and are curious about where the actual infection is: kidneys? ureters? bladder? urethra?

We like to know if the infection is in the kidneys, because that can be a much more serious and hard to manage infection, so it is better to be prepared at the outset. Do you have to do an ultrasound to see what shape the kidneys are in?

One thing you can do instead is watch the dog pee. Does the blood appear in the urine stream at a particular time? If it’s in the entire stream, that’s not much help. However, if it is at the very beginning, you can suspect that the infection is fairly far down in the urinary tract, so that it gets washed out early in urination. (You’d be less likely to suspect kidney involvement in this case.) If you see blood only at the very end of the stream, you can suspect that the bleeding is in the bladder, pooling at the bottom of the bladder and therefore not getting out until very late in urination. (Here again, the kidneys may be safe.)

Of course, there are lots of other tests that get done, but I like the simplicity of this part of the equation. As always, please do not use information you find here to diagnose your dog! If your dog is peeing blood, or even just peeing more often than normal, your dog needs to see a veterinarian.

This week’s test: Small animal medicine/surgery. Why do they always schedule tests in the two most demanding classes right next to each other? This exam is mostly renal stuff (kidney disease, urinary tract infections, uroliths) and endocrine stuff (Addison’s, Cushing’s, hyperthyroidism, hypothyroidism, diabetes).

Veterinary fact of the day: castrating lambs

2010-10-27T09:11:00.000-04:00

I am plowing through flash cards for my upcoming large animal medicine/surgery exam. Current favorite card:

Q: Best time to castrate a lamb?

A: First 12 hours of life, after that too hard to catch

So descriptive in its brevity.

Canine obstetrics

2010-10-26T07:49:00.000-04:00

We had our canine obstetrics lecture recently. After learning about equine obstetrics and bovine obstetrics, I was really glad to get a chance to hear about dogs. Our lecturer was Dr. George, who is an emergency and critical care (ECC) specialist who has particular knowledge of this subject area because he is also a dog breeder.

So you’re an ER vet, and an owner brings her bitch in. The bitch was in stage II (active) labor for an hour, produced one puppy, had contractions for three more hours, and now has stopped having contractions. What do you do?

Your two choices are to perform an immediate C-section, or to give oxytocin to get the contractions restarted. There is no downside to the C-section; it is very safe for mom, and definitely the safest course for the puppies. However, it is very expensive. The oxytocin route is much less expensive, but it may result in some dead puppies, and if it doesn’t work you’ll end up having to do a C-section anyways. Dr. George noted that the most frustrating case is the one in which you give oxytocin and manage to get all but one puppy out, and after five hours of letting her push puppies you finally have to give up and do the C-section after all. So what issues do you take into account when you’re working through these options with the owner?

First, how many more puppies do you expect? Sometimes owners have had radiographs (x-rays) taken and know the minimum number that are in there. (Of course, sometimes puppies hide on radiographs — Dr. George doesn’t know where — and you are likely to get more than you expect.) If you expect a lot more, do the C-section, because you’re fairly likely to end up having to go that route anyways. If you only expect one or two, oxytocin might be a better option.

Second, what are the owner’s constraints and expectations? Dr. George says he gets two kinds of obstetrics emergencies: the chihuahua from the streets of Worcester (i.e., a dog from a low-income area), and the golden retriever from Westborough (i.e., a dog from a high-income area). In the case of the golden from Westborough, the owners are likely to be willing to pay quite a bit to ensure the safety of the puppies, so the C-section is the best option. In the case of the chihuahua from Worcester, the owners may just not have the money, and may not have planned the pregnancy anyways. In that case, go with the oxytocin; the puppies may not survive, but if the alternative is euthanasia because the owners can’t afford the C-section, you’re still doing some good. Dr. George says he will be very frank with owners, asking them to tell him their goals up front. Are we just trying to save mom, or are we doing everything we can for everybody?

I have been really enjoying the canine theriogenology (breeding and obstetrics) section. I’m considering doing some elective time during my clinical months at a practice that specializes in this stuff. What better way to learn more about dog breeds and their genetic problems?

This week’s exam: Our test this Friday is our second Large Animal Medicine and Surgery exam. Cows, cows, cows! After this we are done with cows; the rest of that course will focus on horses. That will be very different, as horse owners’ goals tend to be very different from cow owners’ goals. However, this test looks like a rough one, so I am head-down studying this week.

The joys of scheduling 82 students over 12 months

2010-10-24T17:39:00.000-04:00

As my class nears the beginning of our clinical time (in only 147 days!), my school has to schedule us. For the first three years of vet school, cohorts do almost everything together. A few hours a week are set aside for individual activities, but mostly you show up, sit in a big lecture hall with 81 of your closest friends, and listen while one faculty member after another shows up and talks at you.

Obviously, 82 of us would not fit in the tiny cardiology room or the ER all at once. So for our 12 months of on-campus core rotations, we are split up into little groups. (The final two and a half months of clinical time is all elective time and expected to be mostly off campus.) I do not envy the administrator who has to manage these schedules! We all have requirements (I need a specific week off for my brother’s wedding on the other side of the country; a friend of mine needs a specific six weeks for an elective at a nearby aquarium). And we all have preferences (mostly we want our Ambulatory rotation, which is outdoors in Connecticut, to be in September and not in February).

The scheduling is done in two stages. For the first stage, we are each assigned the order of our major blocks. What’s a major block? Basically, the 12 months is split into four seasons. You do a group of rotations together over the course of three months (one season); that is a major block. So I might do one set of courses in the spring, and someone else might do that same set in the fall.

We were all in lecture when email came from administration that our scheduled block information was now ready and in our mailboxes. Because we all have laptops in lecture we all knew immediately. There was 30 minutes of lecture left. The tension was palpable. One student actually got up and brazenly left lecture, to return with her envelope (and the envelopes belonging to her friends sitting near her). I jiggled all through the next 30 minutes until we had our break and could get our schedules. I am afraid the subsequent lecture was shot as well, as we were all obsessed with our little pieces of paper throughout it.

I mostly but not entirely got the order that I wanted. I will not be doing Ambulatory in the winter. LPK will. I am concerned that she may not survive. I was at that clinic for one day in January for a second-year rotation day, and it almost did me in. “Now we will vaccinate these three dozen calves. You are all going to have to take your gloves off to handle the syringes.”

In a week we will go through a second lottery process to establish the order of the individual rotations within each major block. (Small animal medicine first? Or pathology first?) This is a full day process; we have no lecture scheduled that day and are expected to spend the entire day in the administration building, waiting for each pass through the lottery. (Four blocks, plus two weeks of required on campus electives, means six passes through the lottery.)

And then my schedule for 12 months of my life will be set. If any friends of mine choose to get married and ask me to attend, I may have no way to get time off. (I told my brother that he had to decide on a day for his wedding before the lottery process began, so I could adjust my schedule around it, more than a year ahead of time.) It’s going to be a very different life from the one I am living now.

Links post

2010-10-23T18:24:00.000-04:00

Animals

Do Dogs Inherently Understand Pointing Gestures? (The Other End of the Leash): Patricia McConnell weighs in on the ongoing research and debate about the canine ability to follow human pointing gestures, and whether it is genetically mediated/innate.
Chicken Slaughtering: a day at a mobile poultry processing unit
Domesticating the Fennec: Dog Domestication 2.0? (Retrieverman)
Evolution: The Curious Case of Dogs (Observations of a Nerd)

Meta

“The current phenomenon of ‘bloggers’ should be of serious concern to scientists” (Terra Sigilata)
Science Cafes: Nice idea for getting people interested in science. How well does it work?
The Trouble with Scientists (Speakeasy Science): “Ask yourself... whether young scientists are reward[ed] for spending time on public communication?” It would be awfully nice if, instead of being afraid that my school will notice that I am blogging, I could expect my school to reward me for trying to improve my communication skills. Just saying.

Number Needed to Ban: a new tool for calculating the benefits of banning particular dog breeds

2010-10-20T07:48:00.000-04:00

A study published this month in the Journal of the American Veterinary Association (JAVMA) takes on the issue of whether breed-specific legislation (BSL) is effective. BSL is a tool used by some communities to attempt to reduce injuries from dog bites. The idea is that particular breeds of dogs are responsible for more than their share of injuries, so banning or otherwise controlling those breeds will result in a reduction in injuries. The group of breeds collectively known as “pit bulls” receive the most attention today, though other breeds (Rottweilers, Dobermans, German Shepherds) have received attention in the past.

But does BSL actually work? Experts say no; how the dog is trained and managed is a better predictor of aggression than its breed. Nevertheless, new BSL continues to be enacted. So why do legislators reach for this tool?

The authors of “Use of a number-needed-to-ban calculation to illustrate limitations of breed-specific legislation in increasing the risk of dog bite-related injury” believe that BSL’s appeal comes from:

Misperception of risk. Poor reporting of the number of dog bites that occur and of their severity makes it very difficult for the public to get a handle on how often they occur.
Stereotyping and misinformation. The media may portray particular breeds as especially aggressive, in the face of scientific studies which suggest that they are not.
Erroneous beliefs about efficacy of BSL. There is currently no evidence for the effectiveness of BSL, but there is evidence to suggest that it is ineffective.

The authors hope to provide a tool for use in understanding the effectiveness of BSL, and they hijack some terminology from the medical community to do so. “Number needed to treat” (NNT) is a concept used to understand the effectiveness of a particular medication or therapy. For example, you have a patient showing signs of a stroke. Should you give him tPA (tissue plasminogen activator)? One measure you might use in making this decision is NNT. How many similar patients would you treat with tPA, on average, before you saw one patient improve? A smaller NNT implies a more effective therapy. In human medicine, we expect the NNT of an effective therapy to be in the tens or at most hundreds.

The authors suggested evaluating BSL’s effectiveness using a “number needed to ban” (NNB) concept. If BSL is implemented in a particular community, how many dogs will need to be banned (removed from the community) before one dog bite (or dog bite related injury, or dog bite related fatality) is prevented?

The authors point out that because our knowledge of the true prevalence of dog bites is so poor (many are never reported), this calculation is hard to do. I think the important thing to understand is that what they are offering is a tool that can be applied to different statistics. After all, dog bite prevalence will vary among different communities. This tool can be used to understand the possible benefit of BSL in different communities. It’s an algorithm to apply to a variety of data inputs!

However, the paper would have been really unsatisfying without some numbers, so they applied their algorithm to some statistics (much appreciated, because I hate arithmetic).

Based on the reported number of dog bite related emergency department visits, 5,128 dogs would have to be banned to prevent a single emergency department visit in one year.
In Kansas City, 4,255 dogs would have to be banned to prevent a single emergency department visit in one year.
30,663 dogs would need to be banned to prevent a single reconstructive surgery in one year.
109,495 dogs would need to be banned to prevent a single hospitalization in one year.
59,523 dogs would need to be banned to prevent a single insurance claim in one year.

The authors note that these calculations were based on legislation banning a particular breed or breeds entirely. For legislation which simply requires that dogs of a particular breed(s) be muzzled while in public, these numbers would be even higher, because such legislation would not prevent bites on private property (which is where many of them occur).

It is the authors’ hope that “easily understood communication tools, such as NNB, can help put the lack of efficacy of BSL into perspective and narrow the perception gap.” This is a great tool and I hope we see it used more. I am concerned that proponents of BSL will argue that any tool is only as good as the data put in to it, and that the lack of reliable reporting of dog bites will mean that this tool isn’t itself reliable. However, as long as we are focusing on enacting BSL instead of focusing on understanding the true problem, our data will continue to be flawed. This article represents a step forward in understanding data about the causes of dog bites. Our next step is improving the accuracy of that data.

Patronek GJ, Slater M, & Marder A (2010). Use of a number-needed-to-ban calculation to illustrate limitations of breed-specific legislation in decreasing the risk of dog bite-related injury. Journal of the American Veterinary Medical Association, 237 (7), 788-92 PMID: 20919843

On becoming a vet student: career changes

2010-10-19T09:51:00.000-04:00

A few weeks ago, I was in line for free food before a lunchtime talk, and I overheard the woman in line behind me saying “Yeah, I wish I could go to school here, but it’s kind of late now.” Because I am no good at keeping my mouth shut, I turned around and told her, “I did that. I was a medievalist in college and an online publishing programmer for twelve years after that, and then I went to vet school. I had to go back and take all my basic science prerequisites, so it took me two and a half years of night classes before I could apply. But here I am.” She was intrigued and asked for my email address, but today I realized I never heard from her. So I figured this would make a good blog post for anyone out there who is thinking it’s too late to become a vet.

How did it work? Vet schools tend to require more pre-requisites than medical schools. The basic sciences that everyone has to take to apply to one of these programs are: two semesters of inorganic chemistry; two semesters of organic chemistry; two semesters of biology; two semesters of physics; two semesters of mathematics. The schools I were interested in also required a semester of biochemistry and a semester of genetics, although my biology class had enough genetics in it that I got that requirement waived. It is my understanding that medical schools don’t require the biochemistry and genetics, although they do require that you pass the GMAT, which is a much harder test than the one I had to take, the GRE.

There are plenty of extension schools out there which let post-baccelaureate (post-college) students take classes of all sorts. There are lots of people who go back to do pre-med programs, or finish up the last of their pre-med requirements after college graduation. At age 31, I was on the older side, but there were a few other students in my age bracket. It is definitely tough to afford your mortgage when you are working part-time in order to take two classes at once and get your volunteer experience in, but I was in a hurry to get through the pre-reqs. I could certainly have done fewer at a time and had more time to work; my friend LPK worked full time and took only one class a semester. It is, of course, easier if you have a partner who will support you while you go to school, but I am proof that you can do it while single.

I'd like to put in a particular plug for Harvard Extension School, here, for anyone in the area. That was a very well organized program for post-bac students. Classes were held in the evenings, just once or twice a week (longer at a time, of course). This structure was convenient for people like me who were trying to work during the day. I also took some classes at a school which just dumped me in with the undergraduates. This was socially awkward, of course, but additionally, their schedules meshed poorly with mine. Classes met three times a week, during the day, so that I had to take time off work, and commute much more often. They have intensive classes over the summer; I completed a year’s worth of physics in just seven weeks (I am a “pull the Band-Aid off fast” type of girl). Of course, I did not work during those seven weeks!

I started with inorganic chemistry, and it was overwhelming for someone who had basically never been really introduced to hard science before. (As an undergrad I took a history of astronomy class and an evolutionary biology class to satisfy my requirements. The biology class was responsible for the lowest grade on my college transcript.) I have since heard of The Cartoon Guide to Chemistry, which I really wish I had read before taking that class. It would have been a gentler introduction. I remember being bewildered at this substance, NaCl, which apparently liked to split into Na+ and Cl- — no one ever explained to me why it did that. I was coming from the land of complete ignorance of chemistry and it was a rough transition.

One of my semesters of math was biostatistics. I took it at the graduate level, and was as a result actually able to place out of biostats in my second year of vet school. I am so glad that I did that.

One thing that I figured out for myself, and wish to suggest to other people, is: you can take electives during your pre-vet time, even if you are taking night classes. Electives fit in well in your final semester, after you have completed most of your pre-reqs and your application is pending. I took some classes which I thought would be helpful for my planned career in animal behavior (neurobiology and psychology). I also took one class because I didn’t know if I would ever have the chance to take a class like that again. (The Cognitive Dog. This class is still on offer and can be taken remotely, so you don’t have to live in the Boston area to take it. I highly recommend it for anyone interested in dog cognition. It was just fascinating. It requires no science background at all, though it should not annoy people who do have a science background.)

In addition to academic pre-requisites, veterinary schools require that you have some hands-on experience with animals, particularly of a medical nature. It is nice for this experience to be varied. I found that shelters are eager for volunteers; find a shelter of a large enough size to have a vet on staff, and make it clear that you are interested in shadowing the vet, not just cleaning cages. Some shelters have large animals, as well; getting large animal experience can be difficult. I also simply approached some veterinarians and asked if I could regularly shadow them. The worst they can say is no.

One of the best volunteer experiences I had was at the wildlife clinic at the vet school that was my first choice (and where I am now enrolled). I was not specially interested in wildlife, but I got to interact with students and see what life was like on campus. That was invaluable. If you have a vet school near you, I recommend you call them up and ask to speak to their volunteer coordinator, who can help you find something.

It is never too late to make this career change. My school recently graduated someone who is in her fifties. If you want it enough, the resources are there to help you do it. I am always happy to answer questions from people who are considering becoming veterinarians but not sure how to start. It is doable!

So how can we make things better for dairy cows?

2010-10-18T17:59:00.000-04:00

Recently we had a lecture from Dr. Gray on production medicine. Before I explain what production medicine is, let me give you a feel for what Dr. Gray is like. He is probably the member of our food animal faculty with whom I agree the most about food animal welfare, although we certainly don’t see completely eye to eye. He is a hugely amusing lecturer due to his propensity to tell involved stories about something that happened on the job recently, and to write random bits of them on the whiteboard.

This particular whiteboard was such a work of art that I convinced my classmate LPS to photograph half of it, at risk of looking like a nerd in front of the class. You will note that, at one point, Dr. Gray was telling how he had made a plan with a client to meet on a particular date, and he wrote the date on the board. (I was tempted to raise my hand to ask if that would be on the test, but since I had sassed him twice in lecture on the previous day, I decided everyone would be happiest if I kept my mouth shut.) Another friend, LPK, at one point noted that Dr. Gray had erased three milk production curves from the previous day in order to draw a fourth. These were generic milk production curves, i.e., “She makes less, then she makes more, then she makes less.” He could have simply pointed to one of the previous ones. Here, in all its glory, is half of the whiteboard:

(Thanks, LPS! Also: the “countdown to clinics” is maintained by my class, not Dr. Gray. That’s a real count; I will be playing doctor in less than 171 days.)

Dr. Gray explained what production medicine is by telling a story. He was in the truck, driving to lecture a bunch of third year students, when he got a call from the manager of a farm. The owner of the farm had set some financial goals for the farm; he wanted to see them sell 75,000 lbs of milk a day. Since they were currently selling 61,000 lbs, the manager had a problem, and he was calling Dr. Gray to talk about it.

Now, if you are a dairy farmer and you want to sell more milk, you have two ways of doing it. You can milk more cows, or you can get more milk from the cows you already have. Buying or raising more cows involves some overhead costs: if you get too many more, you need to build a new barn. If you try to cram too many into the barns that you already have, they will not do well, and the result will be decreased milk production. This farm manager wanted to convince the cows he had to give him some more milk, and maybe figure out if it was safe to keep a few more cows as well.

There are a lot of factors to take into account in this game. How many cows can you fit? If you have too many, they will all be waiting in line for a long time at the milking parlor. This will eat into their daily quota of lying around chewing their cuds, which will mean poorer quality digestion and less milk. How much milk will each cow produce? This has a lot to do with what she eats. Is she eating as much as you want her to, or is something preventing her from doing so (too many cows at the feed bunk)? Is there a way you can change her diet to provide more energy for her to turn in to milk? If you provide too much energy, her rumen will acidify. At low levels (“sub-clinical rumenal acidosis”) she won’t look sick, but her life expectancy will be shortened, and, you guessed it, she will make less milk. At higher levels, she can have ulcers which eat their way through the wall of her rumen and seed her bloodstream with bacteria. The bacteria make it to her lungs, where they generate clots. And that can kill her in a fairly unpleasant manner.

Production medicine is all about balance. More of a particular factor will give me more milk until it starts giving me less milk. To some extent, the welfare of the cow is in sync with the welfare of the farmer’s bank account. A sick cow doesn’t give as much milk as a healthy one. But to a very large extent, this relationship does not hold true. It often makes more financial sense to sacrifice optimal cow health (accepting sub-clinical rumenal acidosis in many cows in your herd) in the name of income (increased milk production in the remaining cows due to high energy feed). At other times, farmers simply can’t afford veterinary care for every cow that needs it when she might need it.

So do I think dairy farmers are jerks who don’t care about their cows? I absolutely do not. I have a lot of sympathy for their situation, and the ones I have met have been really nice guys who clearly do like their cows. But, to give an example of a population of humans that we all know care about animals — people who love their dogs make bad management choices when they are in bad situations. And dairy farmers are, many of them, in bad situations.

I believe that if they could afford to, more farmers would have smaller farms, with more personal care of their cows, with more cows out on grass. And I believe that almost none of them would skimp on veterinary care if they could afford to give their cows the care they want. But dairy farmers are suffering from very low milk prices right now. They do not have enough income to have the luxury of doing the right thing. They are just trying to get by. They are driven to making bad choices, like packing too many cows into a barn, or sacrificing veterinary care.

Mostly, the small farmers are driven out of business, and the large farmers are taking over, because that makes more financial sense. Dr. Gray reports that a 5,000 cow dairy is the most efficient one. Are large farms worse? Well, if they are more profitable, the cows are likely to get better nutrition and better veterinary care. Other things will be better for them too — the concrete that almost all dairy cows live on will be covered in better bedding, for example.

But in my opinion, the very best farm is the small farm with enough money. On that farm, there are few enough cows that they can be put out on grass sometimes. (Imagine getting 5,000 cows out onto grass, and then onto the next pasture segment a few days later, and then onto the next pasture segment a few days after that, not to mention getting them all to the milking machine at least twice a day.) It is a farm where the farmer can know each of his cows, and notice right away when one of them is not quite right, so that she can receive medical attention promptly. It is a farm where the number of cows is small enough that infectious disease is not a big problem. Are there any farms like this left? Vanishingly few, if any. Dr. Gray opined that the big farm is the farm of the future. The small farm is on its death bed.

I raised my hand and asked Dr. Gray if he thought there was anything veterinarians could to affect this situation, to try to fight against the death of the small farm, or otherwise take steps to change the situation of dairy cows. He replied, “No.” In his opinion, no one really cares all that much about cows. There are some people who do, like a lot of the students in the class, but he suggested that we were the exception, when you look at society as a whole.

The lecture moved on, but I wasn’t done. During the break, I talked to Dr. Gray more, along with Daria, a classmate of mine who has worked on farms and is interested in food animal medicine and herd health. I pointed out that people do care about food animals; they voted “yes” on Prop 2 in California, knowing that it would almost certainly raise food prices. Daria added that consumers do have power to affect farm animal practices; there is almost no milk sold in the Northeast from cows that were given rBST (a synthetic growth hormone), and that is because there was no demand for that milk from consumers.

Dr. Gray protested that neither of those things were useful things to do. Proposition 2 enacted rules with no science behind them and may not actually make things better for animals. And science shows that rBST isn’t bad for cows or people. (I’m not going to get into whether I agree with either of those statements; they are his viewpoint.)

I replied that the point is that consumers have power. What they are lacking is information. I noted that I have always purchased organic milk in grocery stores. Until I started vet school, I was under the misapprehension that this would lead to at least somewhat improved welfare for the cows in question. I now realize that that is not true. But I have always been willing to spend more money to purchase a better life for the cow whose milk I drink. I believe that other people agree with me.

The problem is that people don’t know how to vote with their pocketbooks for a good life for cows. They don’t necessarily know whether or not dairy cows have a good life. (My opinion: it is not by any means torture. But it is unpleasant enough that since taking this class I have stopped buying milk in the grocery store.) So my answer to the question “what can veterinarians do?” is this: veterinarians can educate.

What can you do? Unfortunately, there isn’t a good answer to this question.

Buy organic milk at the grocery store? This will probably not make any contribution to dairy cow welfare. Farmers who produce organic milk have an incentive to not treat sick cows, because once a cow has had any antibiotics at all, her milk is no longer considered organic, and will bring a lower price. Regulations about what is organic make no specifications about humane handling of cows.
Buy less milk? I certainly think that Americans consume too much milk (mostly in the form of cheese). But buying less milk right now is probably going to have the immediate effect of driving more small farmers out of business, which is not the best thing from a dairy cow’s welfare standpoint.
Buy milk from farms with grass-fed cows. This is what I am trying to do, but it is awfully hard to find farms like this! I have failed to find milk from grass-fed cows in my area, but my farmer’s market does provide me with cheese and yogurt made from milk from grass-fed cows. Check out your local farmer’s market. Does your town lack a farmer’s market? Maybe you can start one. The market in my town was started by one guy with a lot of enthusiasm a few years ago. Does your town’s farmer’s market not have milk, cheese, or yogurt from grass-fed cows? Let the organizers know that you’d like it to. Or maybe you can set up a buying co-op. Think out of the box.

This is a hard question and I don’t see a good solution in sight. How can consumers support particular farms when grocery stores provide them with food that has passed through so many middle-men that there is no way of knowing exactly who they are supporting? Hopefully farmer’s markets will continue to flourish and will start providing a usable mechanism for consumers to connect directly with the source of their food, so that they can more easily evaluate the welfare of the animals whose owners they are supporting. For now, I leave you with a photograph of the farm where the cows live who produce the milk in the yogurt and cheese I have been buying lately:

Why veterinary anesthesia is a thrill a minute

2010-10-17T09:44:00.000-04:00

Last week I had my anesthesia and analgesia final exam. Some people seem to think that anesthesia is boring. (The Amateur Transplants refute that fallacy pretty well.) Anesthesia is in fact pretty complicated. I sort of wished that the choices you have to make for each anesthesia case could be written out in a huge decision tree, but I didn’t have the energy to do it myself. Roughly, here’s how it goes.

Premedication

First, you might want to make the animal sleepy so it doesn’t try to bite you, kick you, or run away from you. The choice of sedative or tranquilizer here is dependent on a lot of factors. How old or young is the animal? (Foals may not need any premedication at all.) How sick is it? (Healthy animals benefit from different premedications than critically ill ones.) Does it have heart disease? (Many sedative/anesthetic drugs depress the function of heart muscle and could kill an animal with heart disease.) And, of course, what species is it? For this exam, we learned details about the kinds of drugs that were best for dogs, cats, horses, goats, sheep, cows, llamas, and alpcas. We did a whirlwind tour of issues in rabbits, ferrets, rats and mice, birds, lizards, and snakes.

Induction

Once the animal is premedicated and drowsy (or if it is naturally unlikely to protest), the next step is to induce anesthesia. Many of the same questions of drugs come up, and many of the same drugs are used for this stage of the process, just in different amounts or given by different methods. It is nice to have the animal mellow for this stage, because commonly the next set of drugs is given intravenously. It is best to put in an IV catheter to do this. A catheter allows easy access later. This is useful to give more induction agent, as they are sometimes given in bursts; to give a reversal agent if necessary, which you may have to do in a hurry if there are problems; or to give other drugs while the animal is anesthetized, such as antibiotics or pain medication, without having to find a vein again.

Maintenance

Once anesthesia has been induced, it has to be maintained. You don’t just knock an animal out and hope it stays out for as long as you need — well, actually, sometimes you do. The question is how long you need to keep the animal under, how painful the procedure is going to be, and sometimes whether you have the equipment for your preferred maintenance method. If you are in the field with a horse that can’t be brought in to a hospital, you will probably not choose to intubate the horse and maintain it with an inhalant anesthetic. For a short procedure, one dose of injected anesthetic might be sufficient, or anesthesia could be maintained by an IV drip. On the other hand, for most surgeries on dogs in a veterinary hospital you will choose to employ an inhalant anesthetic.

How are you going to get the inhalant gas into the animal? Most commonly you will intubate (put a tube down the animal’s throat). In some cases, you will not be able to do that, and will put a mask on the animal’s face instead. We don’t like masks because they are liable to leak and you don’t want anyone but the animal to be getting that gas — the veterinarian would be breathing small amounts of anesthetic gas during every surgery, which is not a good thing. But sometimes intubation isn’t possible, particularly for very small animals. Interestingly, we were taught that you do intubate snakes, and that in fact you do so before inducing anesthesia — you sedate them and then put the tube in while they are still awake.

Recovery and post-operative analgesia

When the animal wakes up, there are another host of questions. Some animals are more liable to regurgitate than others. Regurgitation is a Bad Thing (it can lead to inhaled stomach contents and aspiration pneumonia, which may be fatal), and so extubation may be done using different techniques to avoid it, depending on the species.

Post-operative pain control is also extremely varied among species. As a general rule of thumb, you go for NSAIDs in horses and cows, but opioids in dogs and cats. Opioids can reduce gut motility, which is bad in animals with big complicated stomachs like horses and cows. (However, we do still use them in those animals.) On the other hand, NSAIDs can cause kidney issues in dogs and cats, while horses and cows handle those drugs really well.

NSAIDs are particularly interesting in veterinary medicine. In human medicine, there was an attempt to find COX2-selective NSAIDs, which would inhibit only the COX2 form of the enzyme (which is involved in pain) and not the COX1 form (which is essential to normal stomach wall function, among other things), in the hopes of finding NSAIDs which handled pain without causing stomach ulcers. Unfortunately, COX2-selective NSAIDs have turned out to be problematic in human medicine, causing an increased risk for heart attack, among other things. These side effects have not manifested in veterinary patients on COX2-selective NSAIDs, however, and most of the NSAIDs that we give dogs are COX2-selective. Interestingly, the COX2 selectivity of any particular NSAID is different in different species. In other words, a drug that selectively inhibits COX2 in a dog may inhibit COX1 and COX2 equally in a human.

Which leads me to my public service announcement of the day: acetaminophen (Tylenol) can kill a cat, and ibuprofen (Advil) can destroy a dog’s kidneys. Always ask your veterinarian before giving your pet any form of pain relief. There’s lots out there for them, but the exact drugs that are appropriate differ hugely between species.

Goodbye rinderpest

2010-10-16T09:27:00.001-04:00

The UN announced this week that the rinderpest virus has been eradicated. Rinderpest kills — oh wait, killed — cattle in Asia and Africa. I learned about it in microbiology during second year.

This is a really good example of One Health in action. Eradicating rinderpest was a huge undertaking. Complete eradication of a virus has only happened once before, with smallpox. So did we take this on just out of sympathy for sick cattle? No, this effort was prioritized because of the humans whose livelihoods (and dinners) depended on their livestock. To have healthy humans, you need healthy animals. That’s the essence of One Health — veterinarians and human doctors working together.

I would like to point out how heavily veterinarians were involved in this process. They helped identify the disease, develop a vaccine, test the vaccine, and they certainly were out there getting their hands dirty making sure the vaccine was in use (getting it to the people who needed it and educating those people about why they needed it).

[ETA: See a really interesting history of the development of the rinderpest vaccine at Speaking of Research (as noted in the comments on this post).]

Veterinarians accused of predatory lending

2010-10-13T07:36:00.000-04:00

Really interesting article in VIN News: Health credit programs: safety net or predatory lending? Apparently the New York State Attorney General’s Office is investigating CareCredit, alleging that it “preys on seniors and vulnerable patients.” CareCredit is used at my school’s veterinary hospital, and many others, to provide on-the-spot credit for people who can’t pay their veterinary bills but do want to find a way to afford a procedure. (The alternative in many, I’m guessing most, cases is euthanasia of the pet.)

I think CareCredit is really important; without it, people who aren’t prepared for how high veterinary medical expenses can be these days would have to euthanize their pets instead of getting treatment. The New York State Attorney General's Office reports the following consumer complaints (it is not clear how many of the providers involved were veterinarians):

Health care providers misled them that CareCredit comes interest-free when in fact interest is charged when balances aren’t paid off following a promotional period of six to 18 months.

I wonder how many of these people were told of the card’s terms but failed to absorb them due to the emotional overload that can happen when your animal is in the ER and extremely sick. It does sound like veterinarians need to be a lot more careful in explaining those terms.

Services proposed but never performed were charged to CareCredit accounts, and account holders were unable to obtain refunds.

That is upsetting. I don’t think it’s a problem with CareCredit, though. I think it’s a problem with individual practitioners.

Medical offices pressed clients to use CareCredit even when clients had the cash to pay.

Both upsetting and a potential problem with CareCredit; I’ll be curious to see where this part of the investigation goes. More specifics would be nice, too. Since CareCredit is interest-free for some period of time, it may actually be in a customer’s best interest to use it, if they are sure they can pay it down promptly.

In general, I would hope to see legal consequences for practitioners who behaved illegally or unethically. I would hope not to see consequences for CareCredit if the only problem is with individual practitioners.

The article goes on to quote Jeff Stillinger, a practice management consultant and Certified Veterinary Assistant:

“We in the industry have failed miserably with reminding the client they need to budget and save... I have never once been handed, or handed out, a puppy/kitten package that contains such information. We don’t have to go overboard and do it for them, or teach them how. That’s not our responsibility. We simply need to remind them it needs to be done.”

I agree. I think veterinary culture emphasizes stepping back, letting the client make their own decisions, which is good — but when that is at the expense of failing to educate, it is bad. People have no way of knowing when they buy a puppy that a visit to the ER after a bad car accident could cost thousands of dollars. It’s our job to prepare them for that.

How to learn how to spay a dog, addendum: uterus removal

2010-10-12T19:08:00.001-04:00

Today I took a uterus out of a dog! As you may remember, when I did my spay lab, my dog unexpectedly arrived pre-spayed. I expected to have to repeat the entire lab, but it turned out that a member of my class, Minerva, couldn’t remove her spay dog’s uterus for religious reasons. We asked the course head if I could take out the uterus for Minerva, while she would do the rest of the surgery (basically opening and closing the dog). The course head agreed, so it was a go.

I showed up at a decadent 8 am. The spay lab students already had been in the clinic for two hours; the dogs had received their premedication, anesthesia had been induced, and they were on the tables, already clipped, scrubbed, and draped. It was a little disconcerting to meet this dog, whose uterus I was going to remove, as just a bare belly under a window in the drapes. I can’t even tell you for sure what color her fur was.

Minerva made the incision and found the uterus. I confess to a moment of nervousness: maybe I was cursed. Maybe this dog would also be uterus-free. (Minerva noted that the dog had apparently had puppies recently, so this seemed unlikely.) And then came time for the uterus removal.

Dog uteruses are a little different from the human variety; they are Y-shaped, with a small body and two long uterine horns, where the puppies would grow. (I don’t know why it is adaptive for them to have such a different uterine shape. I don’t think it has to do with number of offspring in a litter, because horses have twins no more often than humans do, but their uteruses also have long horns, just like cows, cats, sheep, and goats.)

So what Minerva found was the left uterine horn, with the ovary at the end. At that end, the whole structure attaches to the body wall in two places. The suspensory ligament is a small ligament running from near the ovary to the body wall; it can just be broken manually, no big deal. Then the pedicle connects the uterine horn to the body wall more extensively.

The pedicle is the bit that is harder to separate. First it must be clamped twice, using carmault forceps, which are long curved forceps which I am told are special for spays. Then you double ligate the pedicle — tie it off twice so that when you cut, it does not bleed. I placed a loop of suture material around one clamp, removed the clamp, tightened the suture very very tight, and made a very secure knot. (Knot tying was a skill we had to learn before being allowed in the door.)

I did the same for the second suture, but for that one, I just moved the clamp up a little, so that I had a clamp to cut against. I made sure to have hold of the pedicle with a smaller forceps, below the ligatures, so that when it was cut it wouldn’t jump back into the abdomen before I had a chance to look at it. Then I cut above my ligatures. I looked carefully at the stump: any extra bleeding? No, it looked good. So I let go of it and watched as it fell back into the abdomen. Now one horn of the uterus was free.

I did the same thing on the other side. The right side is a little harder. All the organs on the left side are pushed down a little towards the dog’s tail to make room for the heart, which means that the uterine horn is a little easier to get hold of on that side. On the right side, the horn was closer to the dog’s head (“more cranial”). I cut it away, and now the entire uterus could be pulled out of the abdomen (“exteriorized”). Minerva and I looked carefully to make sure nothing had come out with it that needed to stay in.

Finally, the uterus is (obviously) attached at the tail (“caudal”) end of the dog — where the babies come out! I double clamped the uterine body above the cervix, and tied it off twice. I cut and inspected and released. And then the dog was spayed.

At that point I stepped back and let Minerva take over. I wrote up a detailed surgery report, using somewhat different words than I have used here, and then I was done, even with some free time before my lunch meeting to do things like write this up. It feels so good to have actually taken out a uterus! (If you'd asked me a few years ago if I'd ever write that sentence, I would have thought you were insane.)

[How to learn how to spay a dog, part 1: Basic skills]
[How to learn how to spay a dog, part 2: Anesthesia]
[How to learn how to spay a dog, part 3: Surgery]

Links post

2010-10-10T13:13:00.000-04:00

Animals/veterinary

“Hoarding” and “warehousing” arise from traditional, not no-kill, shelter models (Pet Connection): Nice overview of the ideal version of the No Kill shelter movement. I definitely think this version of No Kill is a good idea. The version described to me in school differs from what Christie describes here. My conclusion is that there are good shelters and bad shelters, and some of each like to call themselves No Kill. The name you use isn’t important; the policies you implement are, and the approach described here is one I support.
Can veterinarians and pet owners trust compounding pharmacies? (Pet Connection)
The 24th Grade: How to make a veterinarian (Pet Connection)
Raw Diets and Assistance Dogs (The Other End of the Leash)
The Evolvability Of Dogs: A Journey From Mongrels To Poodles (Ursula Goodenough)
Friday Sprog Blogging: rabbit behavior (Ethics and Science): I am totally enjoying the interactions between a Science Mom and her offspring as she demonstrates a scientific perspective on life using a Socratic approach.
Med Student Q&A (A Cartoon Guide to Becoming a Doctor): In which we learn about “dirty Netters.” That’s nice — vet students have “dirty Millers.” THEY GET REALLY DIRTY.

Meta science blogging

Should science journalists take sides? (Not Exactly Rocket Science)
What Variant of Science Communicator are you? (Science and the Media) I think I am “Communicatus Scientificus Var. Obsesionatii.”

Veterinary terminology: signs and symptoms

2010-10-09T15:29:00.000-04:00

Way back in my first year of vet school, faculty were very concerned with teaching us the basics of how to talk like vets. One of the first pieces of terminology that was explained to us was that animals don’t often have “symptoms”; they have “signs.” A symptom is something that you report. “I’m feeling nauseated.” A sign is something that someone else observes: “My dog vomited three times yesterday.” I guess Kanzi could have symptoms, but I expect all my patients to have signs.

What I did yesterday: Theriogenology midterm (cow sex, sheep/goat sex, horse sex. That class had lots of amusing photos in the powerpoints, but I didn’t feel right stealing any of them to show you guys. I considered googling for interesting replacements, but just in time realized my mistake before making a web search that I would have really regretted). Got out early enough to go to the gym. Two hours of dermatology lecture. Spent lunch running home to pick up my laptop’s power cord (oops). Two hours of anesthesia case studies (our anesthesia final is next week). One hour of large animal medicine/surgery: how milking machines work.

Shades of grey in the ethics of animal research

2010-10-05T19:57:00.000-04:00

This afternoon I read Animal Research: Animal Welfare vs. Animal Rights, by Walter Jessen of Highlight Health. The article addressed some myths about animal research, explaining why it is necessary and what we do to maintain the health of research animals. In many ways, it was a typical volley in the debate between scientists and animal rightists about animal research.

I have issues with the arguments used by both sides of this debate, which miss a lot of shades of gray in the question about whether it is wrong to perform research on animals. The article ably addressed some of the myths and mis-framings presented by the animal rights side of the debate. That is important communication to provide. However, it introduced some mis-framings of its own, and I’d like to address those here, while recognizing that the article is completely factually correct.

Animal rights vs. animal welfare

Jessen starts by defining his terms (“animal rights” and “animal welfare”). He chooses the most extreme position for animal rightists, describing them as people who “reject eating any animal as food, abstain from taking any over-the-counter drug and/or prescription medication, and refuse all vaccinations and/or medical treatment.”

In my experience, that description characterizes a truly extreme group. It leaves out those who take a more graded approach, such as a belief that animals shouldn’t be eaten, but may be used in some forms of research. This may be an attempt to frame the argument in terms of scientists versus fringe crazies. What about the people who fit in neither camp? Isn’t that where most of us lie, accepting medical treatments but feeling somewhat uncomfortable about animal research? Can’t scientists address that discomfort without resorting to the suggestion that anyone who feels that animal research may be wrong must reject all medical treatment?

Immoral and necessary

Jessen argues that animal research is necessary because “animal systems provide invaluable and irreplaceable insights into human systems.” That is completely true (and I would add that animal research provides invaluable and irreplaceable insights into animal systems as well. It isn’t only useful in human medicine). Jessen doesn’t go so far as to say that because animal research is necessary, choosing to perform it is also moral. But that seems to me to be the point of his article: we don’t need to feel bad about this; this is necessary. But just because something is necessary doesn’t mean we should be completely comfortable with it. Can’t animal research be both necessary and immoral? Can’t we choose as a society to do it without absolving ourselves from feeling disturbed by it? When we read about an interesting experiment that involved animal research, can’t we think how cool the results are and how we feel sorry for the animals?

A mountain climber is stranded in a snowstorm. Help won’t come for days. His companion dies. Our hero eats his friend so that he won’t starve to death himself. Immoral, but necessary. He does it, and he knows it is the right choice. But he feels terrible about doing it. Perhaps he will take care to provide for his companion’s children.

A single mother in a country that does not have welfare loses her job through no fault of her own. Her savings are gone. She loses her home. Living on the street, she steals food to give her children. She knows it is wrong, and she feels bad about it. But she also knows it’s the right choice.

Recently I had elective surgery. After the surgery, I chose to use painkillers that surely had been tested on animals. I know that animal research is wrong, and I feel bad about it. But I also know that it is the right choice to continue to learn about how to keep humans and animals healthy.

The debate about animal research is often presented as two choices: it’s wrong, and we should never do it; or it is necessary, so we shouldn’t feel bad about it. We should feel bad about it. And we should continue to do it. (But we should do it somewhat differently than we do now. Read on.)

Are research animals comfortable?

Jessen writes that “the vast majority of biomedical research does not result in significant discomfort or distress to research animals.” I think he is addressing the misconception that research animals spend the majority of their lives in a great deal of pain, and wants to make the point that they are kept mostly pain-free. However, he writes that “57 percent of all research procedures with animals involved no more than slight or momentary pain or distress.” I note that that leaves 43 percent of procedures that do involve more than momentary pain or distress. That’s a significant fraction.

He also writes that “thirty-eight percent of the research procedures employed anesthesia and post- operative painkillers.” I should hope that painkillers were employed where indicated! But I also would like to point out that painkillers don’t remove all the pain. Would you choose to undergo an unnecessary surgery if you were offered the best possible pain relief afterwards? What if you were offered the surgery but had to recover in a hospital where no one spoke your language, and you had no way of requesting more painkillers if the standard dose was not enough for you?

I’d also like to move the discussion away from pain, which both sides of the debate are (in my opinion) overly focused on. Pain is sometimes necessary in research. What isn’t always necessary is keeping animals in cramped quarters lacking environmental enrichment. I have seen facilities where the mice and rats lack even an exercise wheel, and where there are multiple animals in a cage so small I wouldn’t feel comfortable keeping even a single pet rat in it. That’s not necessary; that’s a choice, due to the fact that more space and more enrichment is expensive.

Again, I don’t think the argument has to be so black and white. We don’t have to argue that research animals are in constant, excruciating pain (because that is untrue). But we can also admit that research animals do often (possibly 43 percent of the time) experience pain as part of the research process. We can feel bad about that, but still do it, because the alternative is so unthinkable. And we can accept that if we’re asking these animals to give up their lives, we don’t also need to ask them to live in such unenriched environments. They require mental stimulation just like we do. If they were so different from us, we wouldn’t be using them to model us.

The indifference of researchers

Jessen argues that “researchers are deeply concerned about the condition of the animals they study.” I agree. Researchers aren’t unfeeling monsters, and I wish that the people arguing on the other side of this divide would stop trying to make them out to be.

However, I think researchers often (not always, but often) subscribe to the black and white version of this particular moral dilemma: it is necessary, so I don’t need to feel bad about it. I have every respect for and sympathy with someone who is living day in, day out with animals that they know will die at the end of the experiment. It would be easier if the cages were big enough, if the animals didn’t lack enrichment, if the painkillers were always sufficient and took away all the pain, if the animals had some place to go after non-terminal experiments. But despite my sympathy for the research community, I would like to see a little more effort on their part to address some welfare issues, and to recognize the moral difficulties inherent in animal research. I do think that it is possible to do animal research, and still sympathize with the viewpoint of people out there who find the idea of animal research disturbing. It should be disturbing. Even though it is necessary.

Moving forward

Am I saying that everyone who benefits from animal research should be guilt-stricken all the time? Of course not. That wouldn’t be very productive. I am saying we should recognize the shades of grey. And that, as a society, we should feel bad enough about animal research to make improving lab animal welfare more of a priority. More of the money that goes to research could go to making the lives of research animals more comfortable. (If a pet rat lives in a bigger cage, so should a research rat!) If they are giving their lives for us, and we recognize that that is wrong, we should also recognize that it is our responsibility to make their lives not just as pain free as possible, but as good as possible. We’re doing a decent job on the former. I don’t think we are working anywhere near hard enough on the latter.

Women in veterinary medicine

2010-09-28T19:38:00.000-04:00

Men make up around 12% of the students in my veterinary school. Yesterday, a guest lecturer commented on that, and noted that in another school, a recent year had no male students at all. I posted a while back about the contributions of improved large animal sedation to the introduction of women into veterinary medicine, which was once a male-dominated profession. Commenters have noted that other factors were almost certainly in play as well. But improved sedation methods in large animals aren’t going to explain why women are starting to dominate this profession rather than being content with half of it.

Interestingly, women do not dominate human medical schools in the same way. Johns Hopkins reports that their classes are made up of 50/50 male and female students. There has also been some commentary in the blogosphere recently about how many fewer female science bloggers are out there, with notes that women are as likely as men to get PhDs, but less likely to stay in academia.

So why are there more women becoming veterinarians these days than men? I don’t think anyone knows. I have two personal theories:

Vet med is often seen as a caretaking profession, something that may appeal strongly to more women than men.
Why vet med and not human med? One difference is that vet med pays a lot less. Are women more tolerant of low pay than men?

Any other ideas?

Veterinary fact of the day: Itchy dogs

2010-09-27T21:44:00.000-04:00

A few weeks ago we started our Clinical Dermatology class, and next week is the first test. It’s been a particularly useful class for me on account of my itchy golden retriever. Jack has always itched from September through November, on his belly, armpits, feet, and face. My dermatology notes taught me: he probably has atopic dermatitis, or non-contagious, itchy inflammation of the skin. Atopic dogs very often show this exact distribution of itchiness (or pruritis, to use the technical term). Many atopic dogs are allergic to dust mites, and many benefit from shampooing to remove allergens. (I literally put down my notes, got up, vacuumed my bedroom floor, and put Jack’s bedding in the wash. It is amazing that I know for sure that I am allergic to dust mites — I’ve been tested — and yet it takes learning that my dog may just possibly be allergic to them to get me to vacuum.)

There are lots of other approaches to managing an atopic dog; cleaning up dust mites is just the easiest, and a good approach in a dog that is not all that itchy. Anti-histamines may or may not help, but are very safe to try in case they do help. Their main side effect is to make your dog sleepy — which in Jack’s case is probably the main mechanism whereby they take care of the itching. Atopic dogs can scratch their fur off (alopecia) and have thickened skin (lichenification), along with other problems.

I hesitated at first to write this post for fear that people would try to fix their atopic dogs on their own. You guys wouldn’t do that, would you? You will of course call your vet for advice before trying to give any medication to a dog, even something safe like an anti-histamine. And if you think your dog is uncomfortably itchy, don’t just vacuum — take him to a vet, starting with a general practitioner and moving on to a dermatologist if you need to.

What I did today: Today was one of the dreaded “eight hours of lecture” days. Two hours of anesthesia, two hours of dermatology; lunch (during which I went to a talk about research on whales in the Arctic, very cool, but that made it nine hours of lecture); two hours of large animal medicine/surgery; two hours of ethics. Phew!

Veterinary fact of the day: measuring the scrotal circumference of a bull

2010-09-26T10:00:00.000-04:00

Two weeks ago we started a new class, Theriogenology, about the medicine of reproduction. (What do you do if she has trouble getting pregnant? What do you do if she has trouble during her pregnancy? Etc.) So far it has all been about cattle, though we will get into other species soon. Much of the veterinary work for the dairy industry specifically is about timing pregnancies, making sure cows get pregnant promptly, and managing herd health reproductive problems.

We had six hours of lecture on cows, and finished up with two hours on bulls. The Society for Theriogenology has guidelines on how to perform a breeding soundness exam on the bull. Is he physically healthy enough to mount a cow? Is the circumference of his scrotum large enough to suggest that he has plenty of sperm (more important for his ability to service multiple cows sequentially than for his ability to get lots of sperm into a single cow)? Are his sperm well-formed and mobile, and mobile in the right direction (forward, not backward)?

Bull scrotums contain vertically oriented testicles, so it is actually useful to wrap a measuring tape around them. (The circumference should be a minimum of 30 cm in a bull of breeding age.) This sort of measurement is not useful in horses, dogs, pigs, or humans, whose testicles are oriented in a different direction.

Most amusingly, the product used to measure the scrotal circumference, with a feature that lets you see if you’ve wrapped the tape too tight, is called ReliaBull. That made me giggle.

Links post

2010-09-22T09:21:00.000-04:00

Policy

Nonprofit helps pet owners cope with emergency vet bills (Seattle Times)
It’s time to try funding spay/neuter instead of mandating it (Pet Connection)
The Worcester pit bull ordinance passed. The Worcester Animal Rescue League has links to relevant articles. These links are on their “current news” page, so if you visit the page a while down the road, it may have changed. (I think breed specific legislation is a very bad idea.)
In the UK: Young children are being taught to interpret dog body language in a bid to cut the number of attacks. (BBC News) Awesome.

Meta science blogging

Of writers and activists – are science bloggers being ambitious enough? (Not Exactly Rocket Science)
In which I set up a collaboration between a biologist, a farmer and a chimeric chicken (Not Exactly Rocket Science): This is a lovely story about the power of science bloggers to make connections between people and help advance science.

Miscellaneous

Life is One Continuous Mistake (The Other End of the Leash): Life philosophy from Patricia McConnell. McConnell is a very well-known behaviorist who recently rehomed one of her dogs (for very good reasons) and has been writing about it.
Stress Doesn't Cause Ulcers! Or, How To Win a Nobel Prize in One Easy Lesson: Barry Marshall on Being ... Right (The Wrong Stuff): An interview with the guy who drank a bottle of Helicobacter to prove that it causes gastric ulcers (it does). This is one of my favorite stories about a crazy scientist and the power of his convictions.

How to learn how to (not) spay a dog, Part 3: Surgery

2010-09-19T09:37:00.001-04:00

Surgery day. This was one of the most emotionally (and physically) challenging days I’ve had in vet school, which has made it hard to write about. However, the dog did not die, and I did not faint, so let us say that overall it was a success.

The previous day, I had performed anesthesia while Lily spayed “her” dog. Today, she would perform anesthesia for me while I did surgery on mine. My dog was a very nice adult, much calmer than the puppy assigned to Lily, and giving her the premedication was a lot easier. We left her alone to let the sedative take effect while we got our operating table ready and made sure we had all our equipment set out.

I should have known that my luck was going to be bad this day when I looked outside and realized it was bucketing down rain, and that I had left my car doors open. I was already in full operating room gear, with booties and mask and head covering, but Lily (bless her) ran out in the pouring rain to close my car’s windows.

We walked my dog in to the operating room, lifted her on to the table, and Lily put in an intravenous catheter and induced general anesthesia, then intubated her. While Lily was setting up all the monitoring equipment, I shaved the dog’s belly and scrubbed it clean with disinfectant. I checked one more time for a spay scar; we had no history on this dog, who was a stray, but she did not appear to have been already spayed.

During this time, the dog was failing to breathe on her own, and Lily was using the anesthesia machine to give her breaths with the breathing bag. The intern who was helping out explained that it would not at all be unusual for a dog to never breathe on her own for the entire surgery. Thankfully for Lily’s sanity, this dog did start breathing on her own eventually, so Lily could concentrate on learning how to monitor her properly.

I left the room, scrubbed in (hand washing! putting on gown and gloves without touching anything! getting yelled at for getting too close to various unsterile items!), returned, and it was time. I put the scalpel on the dog’s abdomen and pressed down.

Opening the dog was disturbing in a very different way from dissecting a cadaver, which I did a great deal of during my first year of school. Cadavers are cold and sort of sad. Live dogs are warm and not sad, but scarier: I kept worrying that I would hurt her, even though I knew she didn’t feel what I was doing.

The initial incision went smoothly (skin; clean the subcutaneous tissue with scissors; then cut into the body wall, along the fibrous white linea alba, careful not to cut too deep so that you hit organs). I got my spay hook ready to go fish for her uterus, but the intern hollered “Put that away!” and had me stick my bare hand down into the dog’s abdomen.

I pulled out a ureter (cutting the ureter is contraindicated, though it does happen, and I can now verify that it does look like a uterine horn), some jejunum, even some colon. The intern hunted as well. Eventually I asked “Is it supposed to be this hard?” Other classmates had reported failing to find the uterine horn on their own, but I figured the intern should be able to do it. The intern called over the surgery resident and explained that this dog had already probably been spayed, and we needed to be sure. And then the surgery resident had a go.

Eventually the resident doubled the size of the dog’s incision and put in a Balfour retractor to hold the sides of the abdomen open so that she could better look around. I got a nice tour of the inside of a living abdomen. And finally she found it: the little uterine stump. The dog had been spayed previously, and I had just performed my first abdominal explore. But I would not be spaying a dog that day.

So I had to close the dog up. The incision looked huge to me. Closing this sort of incision is done in three steps: first you close the body wall, then the subcutaneous tissue (“the subcu”), then the skin. I sewed the body wall. And sewed and sewed. Sometimes I would realize I had gotten off the fibrous linea alba onto muscle (painful for the dog after she wakes up), and would pull out some stitches and back up. Sometimes the intern would point out I had gotten some subcu, and I would pull out the stitches and back up. Finally the body wall was closed, and I called the resident over. She took a look, declared my stitches too loose, and pulled them all out, every one.

I started over (and she helped). It felt as though I had been sewing linea alba for an hour. I was becoming frustrated, and my initial adrenaline rush was fading. As a result, I was starting to become aware of my body again: I was hypoglycemic, dehydrated, exhausted, and my back was spasming from the hours on my feet leaning over a table. When I am that hungry and tired, I am usually careful not to make important decisions or to do anything requiring manual dexterity until I have eaten and rested, yet here I was placing stitches in the body wall of a dog of whom I had become somewhat fond.

I wondered if this experience was showing me that I was not physically up to the demands of a veterinary internship. Maybe I was only good for research and never meant to practice. I was so hungry. I was so tired. I was so depressed at the idea that this was all for nothing: the dog didn’t need the surgery, and I wasn’t going to get class credit for it, because I wasn’t doing an actual spay. We sewed and sewed, and then I did the next two layers, and finally the surgery was done. All that was left was a pile of paperwork, four hours of lecture, and continued care of my dog until she was discharged 25 hours later.

A few days after the experience, I feel a lot better about it, but it was an emotionally rough day. I felt very bad for the dog. She had a much larger incision than she would have if she had been spayed, because we had to be sure that there was no uterus before we closed her up. And she had incompetently performed sutures, which I am sure are more painful than they would have been if someone who knew what they were doing had put them in. And she didn’t need the surgery in the first place.

So do I now think that it is a bad idea for veterinary students to do their first spays on shelter dogs? Absolutely not. These things happen. This dog would have received an unnecessary surgery no matter what, since the standard of care does not dictate waiting for a dog to go into heat before spaying her. It was inconvenient for me, but the inconvenience is worth it. The program is a good one, and no one did anything wrong.

I did not actually spay a dog, but I did learn a great deal about anesthesia and about surgical procedures. I did open and close a dog, which was very important experience. All students at my school are required to complete two spays during their third year, so I will go through this lab two more times. That won’t leave me an expert on spaying a dog, but there will be lots of other opportunities to practice during my clinical year. I can’t quite say that this particular lab was a good experience for me, but I can say that the program is well designed, finding a good balance between students’ needs for experience and ethical issues.

[How to learn how to spay a dog, Part 1: Basic skills]
[How to learn how to spay a dog, Part 2: Anesthesia]
[How to learn how to spay a dog, addendum: uterus removal]

How to learn how to spay a dog, Part 2: Anesthesia

2010-09-18T09:07:00.004-04:00

Monday evening, at 5 pm, eight of us arrived at the spay clinic. The anesthesia tech who is in charge of the clinc hadn’t arrived yet, but we found that each of the eight dogs in the clinic had one of our names on the front of her cage. We took our dogs outside to let them stretch their legs and pee. Mine was a sweet mid-size dog of a few years of age. My partner, Lily, was assigned a six month old who had the normal energy level of a six month old puppy — she was a handful. Lily was scheduled to spay her puppy (we quickly started referring to them as “our” dogs) on the first day of the lab, and I was scheduled to spay my dog on the second. I would perform anesthesia for Lily on the first day, and she would perform anesthesia for me on the second.

The anesthesia tech and veterinary intern arrived, and helped us draw blood on our dogs. (This was my third time drawing blood. I am still terrible at it.) We tested the blood to make sure that all the dogs were good surgical candidates. Any dog with any medical problem at all would be ineligible for the spay lab program; that dog would need to be spayed by someone with more experience.

Then we gave our dogs physical exams and wrote up our SOAPs (Subjective/Objective Assessment and Plan). We presented our dogs to the veterinary intern. A typical presentation would sound something like: “This is a two year old intact female dog, presenting to the spay clinic for ovariohysterectomy. Her heart rate was...” And so on. The intern was helpful, explaining things to me like “don’t say you found a lesion on her tail, say you found an area of alopecia on the dorsal caudal aspect of her tail.”

Around 7:30 pm we were done. We fed our dogs. Lily and I agreed that I would handle the 9 pm walk that night. I went home, fed my own animals, fed myself, and came back in for the 9 pm walk. I put a note on Lily’s dog’s cage to make sure that no one else gave her more food, since she was scheduled for surgery the next day. Home again, I calculated the drug dosages for Lily’s dog for the next day (since I would be handling her anesthesia), and went to bed.

My alarm went off at 4:45 am the next morning. I was at school by 6 am. We walked our dogs, did another physical exam, and wrote up another SOAP, which was very similar to the previous SOAP from twelve hours before. I fed my dog. Then Lily and I premedicated her puppy. This was difficult, as the puppy didn’t want to hold still, and I had to put a very large needle into her back and inject the premedication cocktail into her muscle. But I managed. The puppy started getting drowsy in a few minutes, while we took care of necessaries before surgery, like food, water, and toilet breaks. By 8 am she was ready and so were we, so we carried the sleepy puppy in to the operating room and put her on the table.

To induce anesthesia, we used an injectable solution. First I put in an IV catheter. This is the second time in my life that I have had to thread a catheter into an animal’s vein; the first time, I almost passed out. I did not even get woozy this time. (Thank you, adrenaline.) Then I injected the anesthesia solution, and the puppy got very sleepy. Good puppy.

Next I put an endotracheal tube down the puppy’s throat. I had been nervous about this, but it was easier than it looks. You can actually see the vocal cords and thread the tube right between them. It helps if the puppy is “deep enough” under anesthesia; we gave her a little more juice after my first try.

Next I hooked her up to the anesthesia machine and started the oxygen and anesthesia gas flowing. We had induced anesthesia with an injectable solution, but maintained it with gas. Gas is a lot easier to control; if you want to change anesthetic depth, you can easily turn it up or down. An injectable solution is out of your hands once it’s in the animal.

Next I added several more monitors and started recording information. Every five minutes, I recorded her heart rate (a machine provided that number), her systolic blood pressure (I took it with a cuff, just as the doctor does it to you), her respiration rate (I counted breaths by watching the breathing bag), and her anesthetic depth (I looked at her eye to see the position of her eyeball, and tested her jaw tone; an eyeball rolled down is a good depth, and a loose but not too loose jaw is also a good depth). If I had time left over, I sometimes listened to her esophageal stethoscope (a stethoscope threaded down her esophagus to lie close to her heart), which let me make sure that her heart was actually echoing the sound I heard on one of the monitors.

Every fifteen minutes, I assessed how much fluid had gone in via her IV catheter, recorded her oxygen pressure, and recorded her temperature. How hard could it be to record a temperature? I had to crawl under the surgical drape and try to see the rectal thermometer. This required a flashlight and lots of craning.

Periodically, the anesthesia tech handed me more meds (pain killers or antibiotics) with instructions on how to administer them. At one point I had three medications stacked up, to be administered “four hours after induction” (in an hour), “when your partner closes the linea alba” (watch partner), and “an hour after the first antibiotics dose.” I had to write down the various times so I didn’t forget them, since I was balancing a few other things in my head at the same time.

The surgery went smoothly. When my partner was done, I turned down the gas and let the puppy breathe pure oxygen for five minutes. Then we unhooked her from the machine, unhooked all the monitors, and carried her back to her cage. When she had swallowed twice (after about ten minutes), I pulled out her breathing tube. We covered her with warm blankets and checked on her frequently while doing paperwork. She did exactly what she was supposed to: went back to sleep after the tube was out, and got steadily warmer.

I had a few minutes to have lunch, then went to four hours of lecture. After lecture, at 5 pm, I walked my dog and helped with clinic cleanup. We planned for Lily to cover the 9 pm walk. The next day I would spay my dog. I was tired, but it felt good to be halfway done, and to have not done a bad job so far.

[How to learn how to spay a dog, Part 1: Basic skills]
[How to learn how to spay a dog, Part 3: Surgery]
[How to learn how to spay a dog, addendum: uterus removal]

How to learn how to spay a dog, part 1: Basic skills

2010-09-15T08:10:00.004-04:00

As my advisor once asked: “How many times do you want a veterinarian performing surgery on your dog to have done that procedure before?” My answer is “a thousand.” But there is a first time for everyone. How do vet students learn how to spay female dogs (a procedure that many vets will do commonly during their careers)? This is real surgery, in which you go into the animal’s body cavity. It is serious stuff and animals could potentially die. So who do we learn on? (Take a moment to think about how you would design the perfect spay learning experience. I would be curious to hear how it compares with my school’s approach.)

At my school, spay lab is scheduled at the beginning of our third year. We are given videos to watch (how to scrub in to surgery, how to suture and knot, how to induce general anesthesia, and how to perform the actual ovariohysterectomy, or spay). And our anesthesia course is front-loaded for the first few weeks. During the second week of classes, before most college students have returned to school, we have a practical exam of several of these skills.

The practical exam (which was one of the more relaxed of the exams given at my school, perhaps to balance the extreme stressfulness of the actual spay) is in four parts. This is how it goes.

Prove that you can gown up: pretend to scrub your hands and arms, showing that you know how to hold your arms so that the dirty water doesn’t run onto the clean parts of your hands; show that you know how to crawl inside surgical gloves and gowns without contaminating yourself.

Next, pick out your tools from a massive pile of them. Be able to tell apart different hemostats (clamps) and scissors; there are lots of different kinds. Put together your “spay pack” of appropriate tools.

Next, prove that you can suture and knot. Do not panic when the surgeons ask for suture patterns that the syllabus said you didn’t have to know.

Finally, show that you know how to write a SOAP (Subjective Objective Assessment and Plan). A surgeon rattles off information about a case. You write down the physical exam findings, your assessment of the dog (what is probably going on with her? What are your rule-outs?), and your plan (what diagnostics would you do if this were your patient?).

Students who pass this exam (and so far as I know, all of us did) are theoretically ready to perform their spay. Where do the spay dogs come from? One option is to purchase dogs, usually purpose-bred animals, perform a spay and possibly some other surgeries, and terminate them at the end of that use. My school has gone a different route. We have a relationship with local area shelters; students perform their spays on shelter dogs or dogs from low income families, under the watchful eyes of surgeons to make sure that we don’t screw up. It’s not ideal; the dogs will be under general anesthesia for longer than if someone with more experience performed the surgery, and they will be more painful when they wake up, again because of our inexperience. But I think it’s the best solution there is, given the situation.

Each student is assigned a partner, and each student is assigned a dog. On the first day, one student spays one dog, while their partner performs anesthesia. On the second day, their roles switch for the other dog. Both jobs are stressful; anesthesia entails monitoring a lot of parameters, and all the little tasks are hard to do at once. Moreover, it is easier to kill a dog with anesthesia gone awry than with a surgical mistake, at least in this surgery. Small groups of students are assigned dates for spay lab throughout the semester; the entire class can’t do the lab all at once, obviously. My spay day happened recently. I’ll report on it in detail in the next posts in this series.

[How to learn how to spay a dog, part 2: Anesthesia]
[How to learn how to spay a dog, part 3: Surgery]
[How to learn how to spay a dog, addendum: uterus removal]

Veterinary fact of the day: changing the face of large animal medicine

2010-09-03T15:45:00.000-04:00

A few days ago in anesthesia lecture, Dr. Drile announced, “Now we are going to learn about xylazine. All of you in the audience who are women, or men under 200 pounds, can be thankful for this drug.” She then plunged into her lecture on xylazine, and it took several minutes for her to get around to explaining why I should be thankful for it, during which time I was mostly distracted by what a weird introduction that had been.

Eventually we got to a slide depicting a small woman leading an enormous draft horse, and Dr. Drile explained. Xylazine is a really excellent sedative/tranquilizer, used primarily in large animals (although also sometimes in small animals). Before we had xylazine for chemical restraint, we had to physically restrain these enormous animals in order to do simple procedures on them. This was difficult and dangerous, and if you were a small person, you couldn’t easily do it. Xylazine hit veterinary medicine around the 1970s, which coincides with an increasing influx of women into the field. The estimates vary for women in veterinary medicine now, but we decidedly dominate numerically. In my first year class, there were 70 women and 12 men. My school recently spent a hefty chunk of change to remodel the anatomy building’s changing rooms, to increase the space in the women’s room at the expense of the men’s. There are, of course, lots of reasons why there are so many more women in veterinary medicine now than there used to be, but this was one I hadn’t considered before.

Thanks to xylazine, veterinary medicine is no longer a wrestling match. I am, accordingly, grateful.

What I did today: Quiz in zoological medicine (not supposed to be hard, and wasn’t). Gym! Two hours of dermatology lecture (new class, very engaging guest speaker). Lunch! (Went to meeting about how the lottery for scheduling our clinical rotations will work.) One hour of small animal medicine lecture (vaccines). Out super early.

Links post

2010-08-31T08:48:00.000-04:00

Dog stuff

Mandatory spay/neuter laws: Follow the (lack of) money (Pet Connection): Why mandatory spay/neuter laws for pets are a bad idea, even though spaying and neutering is a good goal to have.
Canine Dominance: Is the Concept of the Alpha Dog Valid? (Psychology Today) Article by Stanley Coren, PhD. He has written some great books about dog behavior and cognition; look him up if you want more on this.

Local food/food safety stuff

Faeces and flies “found” at US egg farms tied to illness (BBC News): “Officials say chickens’ contact with animal faeces and wildlife are among the main causes of concern as they investigate the source of the salmonella outbreak.” I really hope this story is not spun into “chickens are healthier in cages where they can't come in contact with wildlife.” Infectious disease is a problem when animals live in too-close quarters. Well-managed farms can balance allowing chickens room to move around with disease management. I assert that I am safer eating eggs from backyard chickens (plenty of room to move around, plenty of grass to clean their feet off on, where one sick hen is not going to make all her neighbors sick, because they are not crammed together), even if those chickens interact with wild birds, than eating eggs from factory farms. I don’t have scientific evidence to support this because the studies have not been done (and are hard to do — there are a host of different factors between those two environments to control for).
ButcherShop (Sugar Mountain Farm): Creative solutions to the lack of slaughter facilities in the Northeast: “We are building our own USDA/State inspected on-farm slaughterhouse and butcher shop... Since banks have not been lending we are bootstrapping the construction from our own cash and selling CSA Pre-Buys where customers get free processing in exchange for buying early.” Lack of local slaughter facilities for small farms is the major impediment to an increase in the number of farmers producing humanely-raised meat in the Northeast. Read more about shortage of slaughterhouses, particularly in the Northeast.

Meta-science stuff

How to make a difference – Responsible vaccine advocacy (Science-Based Medicine): Nice article about how to approach the problem of spreading your viewpoint, recognizing that repeating facts over and over is probably not very effective.
Good example of a tag cloud for blogs. This is the interface I really want to see on a larger scale.
Online science blogregator
Peer Review and the Internet (Science-Based Medicine): “Imagine an alternate process by which an article is published online, either on an open site or a secure site that only experts have access to. Then dozens or hundreds of experts can comment on the paper, providing feedback directly to the authors in addition to the editors, who can also respond to the commenters. The result would be more of a dynamic conversation than you get with the current review process. But most importantly, in my opinion, is that you would get a broader range of opinions, and a far greater chance to detect error or bias. An editor or editors can oversee the process, and once it has played itself out the final version of the paper can be published to the public, and become part of the official literature.” Sounds great. One question I have: how do you know when “it has played itself out”?
Asking “Who’s a journalist?” is so 2007 (Global Vue): Proposes a list of questions we should be working on now. (It’s nice when posts don’t just explain why a question is a bad one, but constructively offer alternative questions that we should be asking.)
Supplementary Information: should I stay or should I go? (Martin Fenner): Nice collection of the blog posts about supplemental information and the implications of the Journal of Neuroscience's recent decision to stop accepting it. Fenner comments “This is a perfect example for why we need better systems to track blog posts relating to an article.“ I concur.

Miscellany

(Proposed) World Veterinary Year 2011!

Comparative medicine: what is a wallaby?

2010-08-30T20:45:00.001-04:00

[ETA: this post was included in Grand Rounds Vol. 6 No. 49 — a conference in a tropical island resort. There are lots of great posts of a medical nature there.]

Last night my ex-roommate, now an intern, called me to say that she had a wallaby as a patient. I was enthused. “Wallaby! It is like a baby kangaroo! Is it really cute? You are so lucky. So what’s wrong with it?” It came in to the hospital with diarrhea, apparently, and feels pretty crappy.

This morning I have a lecture on cow diarrhea, and I thought, I wonder what’s wrong with that wallaby? I wonder if this morning’s lecture will give me any idea? Then I thought: What’s a wallaby?

There’s a popular t-shirt among vet students that says “Real doctors treat more than one species.” We learn about the common ones in vet school: dogs, cats, cows, horses. But we are (at least theoretically) responsible for any animal species except for one. What if something you’ve never seen before comes in the door? How do you start to approach that problem?

In our first year nutrition class, we learned how to deal with a related problem: feeding zoo animals. What do you feed a rhinoceros? Well, the lecturer said, what’s a rhinoceros? They are hind gut fermenters, like horses. So if you don’t have any idea what to feed it, feed it like you’d feed a horse. What’s a giraffe? It’s a cow (a foregut fermenter). What’s a tiger? (You can probably manage that one on your own.) You’re not going to do a perfect job of constructing a diet if this is all the information you have, but in a pinch, it can be a good start.

But that’s nutrition. Can you take the same approach in medicine? The medical problems that we see in different kinds of animals seem to mostly be affected by two things: the animal’s basic anatomy, and how we use the animal. Pets (dogs, horses) have congenital problems (hip dysplasia); they have problems associated with old age (heart disease, kidney disease, cancer); they have trauma (hit by car, athletic injuries). Animals with complicated guts (horses, cows) have gut diseases (colic in horses, all sorts of things in cows). Horses have problems with their legs and feet. Food animals have more herd health issues, associated with management problems (poor husbandry) or infections (lots of animals living in close quarters).

So when a general practitioner encounters an animal like a wallaby, one place to start is to ask: What is a wallaby? This one was a pet, so I might put it into the same framework as a dog, expecting diseases of old age rather than diseases of poor herd management.

Of course, this is only a rough place to start. Even the species we know well have very different medical issues. For example, cats have notoriously ineffective livers when it comes to processing medications; acetominophen can kill a cat. That’s an important species difference to know. A general practitioner really should not be seeing something like a wallaby; an animal like that should go to an exotics practitioner. (This one was presumably a patient of the exotics department, but the ER department was keeping an eye on it over the weekend.) But even the exotics practitioner is going to be lacking a lot of information, and may need to engage in some informed guesswork.

The species differences that we have to learn in school make veterinary education a somewhat overwhelming process. But on the flip side, veterinarians have the opportunity to see medicine from a very different perspective from human doctors. Treat multiple species? Veterinarians treat multiple phyla.

Veterinary fact of the day: placing an esophagostomy tube

2010-08-28T18:07:00.000-04:00

Yesterday we learned the theory of how to place an esophagostomy tube. We saw a video of a tube placement on a cadaver dog, but haven’t actually gotten hands-on experience in this area yet. (We may all get to do so before we graduate, though.)

What’s an esophagostomy tube? It’s a feeding tube that goes in through an incision in the animal’s neck, into the esophagus. It is used for animals that will not or cannot eat normally, but can keep food down. So you might use it in an animal with bad facial fractures which cannot move its jaw; you would not use it in an animal which had uncontrolled vomiting (all the food would come right back up).

How do you place it? Put the animal under general anesthesia. Put some forceps into the animal's mouth, into the esophagus. Make an incision in the animal’s neck, right over the esophagus. Poke the foreceps through the esophagus and out the hole in the neck. (Dr. Libbe said at this point: “This part seems kind of scary at first, but it does work!”) The forceps are strong enough to poke through the esophagus and make a hole, but not strong enough to poke through the skin and muscle, which is why you make the incision.

Take the feeding tube and thread it in through the hole in the neck, grab it with the forceps, and pull in out the animal’s mouth. Now you have a tube from outside of the mouth to outside of the neck — not so useful! So turn the mouth-end of the tube around and thread it back down the esophagus in a little loop. When it passes the incision you’ve made, it will lie a little further down the esophagus, and now it is in place: you have a tube passing from outside the neck to inside the esophagus. Suture the tube in place, and you are all done.

What I did yesterday: Two hours of zoo medicine lecture (reptiles). Lunch! (I exercised outside; it was a lovely day. I also did my ethics reading.) Two hours of small animal medicine and surgery lecture (nutritional support). Two hours of ethics lecture/discussion (euthanasia). Home!

A day in the life: ethics from large and small animal vets

2010-08-26T16:46:00.001-04:00

I had trouble choosing just one anecdote to relay from today’s lectures, so I’m going with two, and calling this “a day in the life” (of a third year vet student) rather than “veterinary fact of the day.”

Our large animal medicine and surgery lectures this morning were on oral and GI diseases in cows. Dr. Big (not his real name) started the GI lecture with an overview of the situation in which today’s dairy cow finds herself. He pointed out that ruminants made an interesting gamble a long time ago, relying on bacteria in their huge stomachs to convert their food into energy. Then man started selectively breeding them, and today’s dairy cow looks very different than she did even fifty years ago. A cow today might produce 150 lbs of milk a day during her peak lactation. “I bet half of you don’t even weigh that much,” he said. He went on to opine that almost every disease which we will be learning about during our five hours of GI lecture (not all of that was today!) is man made. “Put the cow on a pasture and she’ll live for 20 years with no problems. Put her in a dairy herd and ask for 150 lbs/day, and her mean life expectancy is 5 years.” (I found it interesting that he equated being on pasture with not producing milk. Every week at my local farmer’s market, I purchase yogurt made from milk from grass-fed dairy cows, out on pasture right here in Massachusetts.) He went on to suggest that we should all read The Omnivore’s Dilemma, which he felt was a very interesting book, “though I don’t think Pollan got it entirely right.”

I just get little hearts in my eyes when food animal vets talk like this. Cows should be on pasture! They get sick because of things we do! It is lovely to see people walking in the grey area between ignoring all welfare implications (“cows do just fine in open barns, they don’t need to be out on grass”) and ignoring the realities of the situation (“no one should ever drink milk because cows shouldn’t be raised the way they are”). Dr. Big thinks we can do better than we do, and he tries to make it happen, by teaching vet students and (I presume) by encouraging farmers to make changes where they can. Compare that to the lecture from the swine practitioner earlier this week, who felt that intensive farming of pigs was best for the pigs’ welfare.

From the other side of the fence, in anesthesia lecture we got a moment to think about the welfare of dogs. Dr. Bonne talked about managing brachycephalic (flat-faced) dogs when they recover from anesthesia. When a dog is under general anesthesia, it has an endotracheal tube (“trach tube”) put down its throat to help it breathe. Most dogs need to have the trach tube removed before they are fully awake. Not brachycephalics. Dr. Bonne showed us a photo of a bulldog: “Look, there he is, wide awake with the tube in, breathing wonderfully. They will do that for an hour or so.” Brachycephalics often have tracheas the width of a tomcat’s, just 5.5 mm in diameter. It is not really enough for them to breathe. When they wake up with a trach tube in, it may be the first time in their lives in which they can breathe easily. Dr. Bonne expounded: “Can you imagine, they must spend so much energy every day, just to breathe. They are perfectly happy with the trach tube in. You should leave it in until the last minute, until they are almost ready to walk out the door. Nobody else tolerates the tube the way that these dogs do.” To my mind, she didn’t go quite far enough — she didn’t ever suggest that perhaps brachycephalics should be bred with a little more care to whether or not they can breathe. But I still appreciated the rant, as far as it went.

What I did today: Two hours of small animal medicine and surgery lecture. Two hours of large animal medicine and surgery lecture. Lunch! (A meeting.) Two hours of anesthesia lecture. Home!

A day in the life

2010-08-23T19:41:00.000-04:00

My “fact of the day” today is just a series of reflections on what was quite a varied day. We started out with two hours of ethics lecture. Mmm, ethics, one of my favorite things. This was the first lecture in this class, and it was enjoyable (despite the fact that I had missed out on the notice that we were supposed to do the reading ahead of time — oops).

We talked about different kinds of ethics: contractarian, utilitarian, relational, rights-based, and respect for nature. The contractarian discussion was the most interesting to me. Do we have relationships with animals based on a contract? The obvious answer is no, because animals can’t understand the concept of a contract and can’t knowingly enter into one. But I argued in class that species can have what is almost like a contract. For example, when we domesticated dogs, we traded food and medical care for work. Is this really a contract? Well, I think it is interesting that we only domesticated some species. Some have proved to not be domesticatable. Does that mean that some species (not the individuals, of course) chose to enter into a contract with our species, and other species chose not to? Only in a very abstract sense, of course, but I like the idea. Some theories of how canid domestication happened suggest that dogs made the first move in the relationship, choosing to start living near us for the benefits of our waste food. Did we domesticate them, or did they wriggle their way in first?

Next we had an hour of large animal medicine and surgery lecture about diseases of pigs. The lecture was given by a swine vet who works closely with intensively-raised pigs — pigs in confinement housing, what has been called a factory farm. She was not interested in discussing the ethics of confinement housing; when she put up a slide with an image of a sow gestation crate (in which the sow does not have room to turn around), she stated preemptively that any discussion about gestation crates could take place after lecture. In other words, she did not feel lecture was an appropriate place for that discussion. Phew. I completely understand her fear that lecture could get derailed in a debate on pig confinement, but I would have at least appreciated a few sentences about why she thinks it’s okay — some moral context. As it was, the contrast to the previous lecture was pretty stark.

Then lunch (I practiced the names of surgical instruments) and then one more hour of ethics lecture, and two more hours of pig diseases lecture. What an oddly-scheduled day.

The post-prandial ethics lecture/discussion was really interesting. It was about the question of whether the AVMA (American Veterinary Medical Association) should extend accreditation to a Mexican veterinary school, the National Autonomous University of Mexico (UNAM). The AVMA already accredits multiple foreign schools, so this is not at all without precedent. UNAM is by many reports an excellent school. So what’s the problem? Apparently, some veterinarians are afraid that accrediting UNAM will result in an influx of Mexican veterinarians to compete with American veterinarians, willing to work for lower salaries. The argument against that viewpoint is that we already have protections in place, requiring that foreigners be paid the same as American workers.

Should the AVMA just get out of accrediting non-American schools all together? The arguments against that are that global standards are good things; and that high standards abroad help keep us safe at home, because it is foreign veterinarians who stand between American animals and the introduction of animal diseases not yet seen on this continent, like the dreaded foot and mouth disease.

I have a sneaking suspicion that I am missing some arguments on this particular issue, because some of the people arguing against accreditation for UNAM are people I otherwise really respect, so I’ll keep my ears pricked and report back here if I learn more.