By Erin Guntrum, Cornell DVM ‘25

I entered veterinary school with a strong interest in pursuing a career in zoological medicine. Over the past few years, I’ve been committed to exploring various aspects of the field and making the most of the many opportunities Cornell has to offer. This has included building a strong foundation in domestic species, working at the Janet L. Swanson Wildlife Hospital, traveling to the Belize Zoo for a week of intense clinical work, participating in the Expanding Horizons program, and others. Now, with careful planning and financial support from the Cornell K. Lisa Yang Center for Wildlife Health’s Student Support Fund, I have been able to put all of it into practice during my fourth-year externship at the Oregon Zoo.

In early November 2024, I traded coasts and boarded a plane to spend six weeks in Portland at the Oregon Zoo, where the veterinary team cares for over 200 species of animals, including many native to North America. The hospital also has an on-site CT scanner and affiliated endocrinology lab that broadens its diagnostic and welfare-based care capabilities.

Research Meets Veterinary Medicine

Part of what had originally inspired my interest in the Oregon Zoo was their Wildlife Endocrine Lab. This lab routinely monitors the fecal hormone levels of many of the zoo's residents, enabling them to assess reproductive status, monitor stress levels, and evaluate welfare in captivity. As someone with a research interest in behavioral endocrinology, I was very excited to work with the lab in addition to my clinical responsibilities.

While at the Oregon Zoo, I teamed up with the endocrinologists and welfare specialists on a project involving the zoo’s polar bears. In zoos worldwide, polar bears are known for their stereotypic pacing behavior, and there are many theories as to the underlying cause, although stress is often an assumed component. As such, many zoo-housed polar bears are kept on anxiolytics and other behavior-modifying medications in an attempt to manage pacing and promote better welfare. However, as often is the case in zoo medicine, regimens for these medications are often extrapolated from experiences with other species, and the true efficacy in polar bears is unknown. So, in a collaborative and ongoing effort, I helped to analyze the bears’ behavioral and hormonal responses as some of their anti-anxiety medications were tapered. It was such an incredible opportunity to be able to bridge my research interests with my passion for zoo medicine on a project that has the potential to better the welfare of zoo-housed animals. It was also a reminder of how much remains to be learned in this field - something that excites me as I navigate my way into zoological medicine.

Conservation in Action

I also participated in ongoing Oregon Zoo conservation initiatives. This included spending several days at the Jonsson Center for Wildlife Conservation, the zoo’s California condor breeding facility. The center is designed to limit human contact as much as possible to maximize the condors’ ability to survive and thrive in the wild upon their release (California condors are listed as critically endangered on the IUCN Red List). During my time at the facility, I assisted veterinarians Gail Huckins and Carlos Sanchez with vaccinating the eight-month-old chicks. After receiving their vaccines and wing tags, the chicks were moved to a fledgling pen with mentor condors to prepare them for their eventual release into the wild. The Oregon Zoo is one of only three U.S. zoos participating in the California condor recovery breeding program. It was a privilege to have played even a very small role in these longstanding efforts to save this species from extinction.

A Day in the Life—from Cougars to Newts

One of my most memorable experiences at the Oregon Zoo was working with the orphaned cougar cubs. With the veterinary team’s support, I was able to take the lead on a case, organizing and performing their intake exams, including physical exams, baseline radiographs, bloodwork, infectious disease testing, and age-appropriate vaccinations. Being “in charge” truly opened my eyes to the amount of work and planning that goes into every procedure in zoo medicine, even the simple ones. I had to consider a wide range of factors, including human safety, a balanced anesthetic protocol, potential anesthetic complications and their management, various infectious disease considerations and associated testing, quarantine protocols, and more. Having such responsibility made me feel more like a (soon-to-be) doctor than any case I’d been involved with previously; I was challenged to think critically and truly reason through a case from start to finish.

Some other memorable cases include a root canal procedure on a North American river otter (my favorite animal), a lameness workup and dental procedure on a North American beaver, and a hoof conformation correction on a bontebok. I was constantly tasked with drawing on knowledge from all the disciplines taught in veterinary school—and then modifying them to fit the needs of the unique species and individuals I was working with.

As has been my experience with my previous explorations of zoological medicine, there is no typical day. One day, I was working up lethargy in a rough-skinned newt, and the next, strategizing medical management of intervertebral disc disease (IVDD) in a lion. At another moment, I was looking into ways to (safely and feasibly) monitor for an intermittent microvascular condition in a chimpanzee, and 20 minutes later, I was doing a quarantine exam on walking stick insects. In zoo medicine, you truly never know where your day might start (or end up), and this challenge has always been what has drawn me to the field.

Reflecting on my Time at the Zoo

I had the absolute privilege of working with approximately 43 different species in some capacity during my time with the Oregon Zoo. It was incredible to be exposed to species I’ve never worked with before and learn new things about those I had. It was inspiring to see just how applicable the foundational knowledge I’ve gained throughout my didactic years and my clinical year has been. Knowing the basics, such as how to interpret bloodwork and radiographs or how to create balanced anesthetic protocols, went a long way in helping me thoroughly work up cases on animals not covered in school, including dwarf mongeese, black rhinos, and lemurs.

I am incredibly grateful to the veterinarians (Drs. Carlos Sanchez, Gail Huckins, Josie Rose, and Tina Batek), veterinary technicians, and animal keeper staff who welcomed me into the Oregon Zoo family for six weeks. They were all amazing mentors who challenged and inspired me to think critically and always strive to expand my abilities as a veterinarian. As I navigate my way into a career in zoological medicine, I look forward to the opportunity to one day call them colleagues.

Erin Guntrum, Class of 2025, is a fourth-year DVM student at the Cornell University College of Veterinary Medicine. She is from Rochester, NY, and received her BS in both Animal Behavior, Ecology, & Conservation (ABEC) and Biological Science from Canisius College (now Canisius University) in 2021. She will be completing a small animal rotating internship at the Animal Medical Center in New York City after graduation and aspires to ultimately work in zoological medicine and conduct research related to behavioral endocrinology and theriogenology.

Photos provided by Erin Guntrum, unless otherwise noted.