Published On January 15, 2013
Whatever makes us human, it’s not our diseases, says Barbara Natterson-Horowitz, a cardiologist at the University of California, Los Angeles. Our shared evolutionary history means the rest of the animal kingdom is also subject to virtually all of our afflictions. That’s the insight behind Natterson-Horowitz’s book (with co-author Kathryn Bowers) Zoobiquity: What Animals Can Teach Us About Health and the Science of Healing. A comparative approach has long been a cornerstone of veterinary education, but physicians aren’t taught to examine illness in other species. If they were, new medical insights might result.
Q: Does veterinary science really know anything medical science doesn’t?
A: Yes. I was consulting on a case of heart failure in an emperor tamarin at the Los Angeles Zoo. The veterinarian warned that if I looked directly into the monkey’s eyes, I’d give her capture myopathy—a form of heart failure triggered by intense fear. Human medical researchers “discovered” a similar syndrome in the early 2000s, but vets have been aware of it for nearly 40 years. Veterinarians are taught that restraining a fearful animal carries a physical risk to the animal”something most human physicians just don’t think about.
Q: What about mental illnesses?
A: Like human “cutters,” some stallions deliberately injure themselves by biting their own flanks. Parrots can develop a feather-plucking disorder that closely resembles trichotillomania (hair-pulling) in humans. A human psychiatrist is likely to see self-injury as a sign of a personality disorder or a history of emotional trauma. But animal experts know that self-injury can be triggered by isolation and boredom. So they place self-injuring animals in closer proximity to one another, encouraging socialization. They also create activities that make the animal forage and work harder to get at its food or work at grooming activities. The veterinary approach to self-injury focuses on how the environment can be changed, as opposed to human medicine, which may focus on changing the individual.
Q: In 2012 hundreds attended your second Zoobiquity conference.
A: The Zoobiquity conferences bring together academic veterinarians and physicians who treat the same diseases. One discussion at our first conference illustrated the potential of this interprofessional approach. A veterinarian mentioned that New World monkeys with diabetes develop larger and more numerous islets (insulin-generating organs), in contrast to humans and Old World monkeys with diabetes, whose islets get damaged by amyloid deposition. Watching the physician do a double-take as he heard this confirmed my belief that important information is hiding in plain sight and accessible through interdisciplinary exchanges. A significant number of New World monkeys at the Los Angeles Zoo appear to go into remission from diabetes. Figuring out the mechanism of remission and understanding why it may be limited to certain monkey groups could be relevant to treating the disease in humans.
Q: What’s the difference between comparative medicine and traditional laboratory animal research?
A: Traditional laboratory medicine typically creates models of human disease in animals. But another important source of knowledge comes from the hundreds of billions of animals in the wild, on farms and in our homes who sometimes get sick, just as we do. For example, some animals (lions and jaguars) are more susceptible to breast cancer, while others (dairy cows and goats) seem to be relatively protected.
Q: How has talking to veterinarians changed you as a physician?
A: I recall a chimpanzee I consulted on with a severe form of heart failure. Had she been my human patient, I would have referred her for a heart transplant evaluation. Watching the veterinarians approach this problem was fascinating for me. The basic medical approach was very similar to human medicine’s, but deeply informed by the patient’s ability to enjoy life and by consideration of patient suffering. I have come to believe that some of the most humanistic medicine today is actually being practiced by doctors whose patients are not human.
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