Scrubs, Stethoscopes, and Scalpels- The Life of a Vet Student: Behind the Scenes at the OKC Zoo

I think my favorite club right now is the ZEW club. Overall, I think they have a lot of very interesting meetings and they offer a lot of unique opportunities. A couple days ago, one of those opportunities was to go to the Oklahoma City Zoo for a background tour of the veterinary hospital. I had been looking forward to this trip since the idea was first brought up a couple of months ago, so of course I was one of the first to sign up and I had been counting down the days since then.

I wasn’t quite sure what to expect on this trip because we weren’t really given that much information about it, but it ended up being incredibly interesting and a lot of fun. One of the things that makes zoo medicine so challenging is that there just isn’t a lot of research out there about it, so a lot of things are still trial and error. And the other issue is that a lot of wild animals will never show clinical signs until the disease is very advanced, because in the wild those weaker diseased animals are the ones who are eaten. So a lot of the time the vets can’t catch something until it’s already too late. I was very interested to hear how zoo veterinarians deal with these issues, as well as the obvious you can’t just go into the tigers pen and give them a vaccination like you could a house cat.

The tour started with a demonstration of the darting methods used. Darting is using either a blow gun or a pressurized version to shoot a tranquilizer dart into an animal to sedate it long enough to work on it. The Oklahoma City zoo had a regular blow gun, for close range, a pistol version powered by pressurized CO2 for longer range and more force, and an assault rifle version also powered by CO2, that had a night scope and everything. The assault rifle is used pretty much exclusively long range on animals that you can’t get anywhere near to or for escaping animals. And the pistol is used for a more intermediate range or on animals like elephants and giraffes with especially thick skin, where a dart from a blow gun would just bounce off. The darts contain a sedative in a pressurized container, and the force of impact from hitting the animal released that pressure and pushes the sedative into the animal. It’s actually a pretty ingenious system. When it works, that is. And our tour guide, the director of the veterinarians at the zoo, was the first to tell us that it doesn’t always work. Sometime the animal has too much adrenaline pumping through its system, which cancels out the tranquilizer. Or sometimes the dart is faulty and the animal doesn’t get the whole injection. And then there is just the whole issue of not always knowing what type of medication would work best for a given species. The rule of thumb given to us was always use something reversible with a wide therapeutic range when you can. Reversible simply means that there is another drug available that will create the opposite effect of a given medicine, like if one drug drops blood pressure there is another that can be given to bring it back up. Not every drug is reversible though, and then you’re left with either trying to find some other way of creating the effects you need or you might lose the animal. And therapeutic range is the dose range of how much to give an animal based on their weight. Since most animals in a zoo are not exactly willing to step on a scale to let you get their weight, drugs with a higher therapeutic range means there is a lesser chance of overdosing that animal. Again, that is not always possible.

Since it is so much work to sedate these animals, zoo veterinarians typically only work on a specific animal about once a year, and while they have the animal under anesthesia they try to do everything that they need to do all at once time. This would include routine things like vaccinations and dentals as well as anything specific to that animal. But you still have to expect the unexpected. Apparently one monkey woke up while under anesthesia and bolted upright and ripped out its own intubation tube, and then went back to sleep. All because it didn’t like have that tube down its trachea. You just never know with zoo animals. I think that would have seriously scarred me for life though, and I’d probably be done working with monkeys.

We also got a look at the radiology department of the hospital, and we got to see some pretty cool radiographs from fish, frogs, birds, and a snake. I’m used to only seeing dogs, cats, and horses, so it was interesting to see the similarities and differences in some of the radiographs. And it was interesting to see how that knowledge from just dog and cat anatomy can be applied to other animals. And even if you don’t know exactly what you’re looking at- like I was completely lost with the fish- usually you can still see something that isn’t quite right, even if you don’t know exactly what it is. Like I could see a huge fuzzy blob that I was pretty sure shouldn’t be there, but I just didn’t know it meant all that fish’s internal organs and ruptured out of the body cavity. I think a lot of that knowledge has to come from experience.

I think that if I were to become a zoo vet, the part that I would find the most difficult is accepting that you will make a ton of mistakes. A lot of them are just unavoidable. The vet giving us the tour told us how she accidentally wiped out an entire colony of tree frogs because she gave them ivermectin, and apparently those tree frogs can’t have ivermectin even though other frogs can. Some things like that aren’t predictable, because there’s no available research to tell you you can or can’t give certain medications to certain animals. A lot of zoo vets won’t try any type of new medications, preferring to let other people try them first and see how they work. Or you have to try it on one animal- as opposed to the entire colony- and see how they react before treating the other animals. There is so much uncertainty in this field regarding certain issues, and no one is really willing to be the first to try something new. At the same point, some zoo vets have close to 2,000 animals under their care every day, so it’s not like they have to time to run studies on zoo animals and medications. You just do the best that you can with the knowledge that you have, and you get creative and hope that it works.

At Oklahoma City Zoo, the veterinarians also oversee the diet of all the animals, and supplements are becoming a big thing for certain animals. We were told one of the most common things the vets are needed to treat is actually arthritis, because the zoo animals are living to such old ages, much older than they would in the wild. Although some animals, especially the monkeys, will pick out every extra supplement and pill hidden away in their food that they don’t want, adding to the challenge. You just have to hope that they don’t get all of it out and get at least a little of the medications or supplements. The budget for food for the animals at OKC zoo is close to $500,000 a year, most of it in fresh produce. 2,000 animals is a lot of animals to feed. And I need to interject something very important- don’t feed the animals at the zoo, and don’t toss things into their cages. Those animals have their diets very carefully regulated, and they do tend to eat foreign objects, probably out of a combination of boredom, curiosity, and hunger. We heard about a sea lion who died from copper toxicity because people kept tossing pennies into the pool, and he ate them all. Or animals ingesting water bottles and getting blocked and ruptured intestines. Besides the python we saw being treated for pneumonia there was radiographs of a snake that had tried to eat several trash items, including a water bottle, and when it couldn’t digest them and pass them it died. So please, don’t put anything into the animals pens. The fences and ditches are there for a reason. /end rant.

Overall, I learned a lot from this trip. It’s such a challenge to work with the more unusual species and not have any idea if what you are going to try and do will actually work or not. I don’t know if I could personally deal with that type of stress, so I have to really admire those who do.

Some pictures from the zoo