Ramar the gorilla is on Celebrex. Hiss Majesty the caiman lizard has been fitted with a prosthesis. And Heidi the reindeer eats hay soaked in water.
They’re geriatric animals at Brookfield Zoo and Shedd Aquarium in Illinois, and their population is increasing, a result of generally improving care for animals in mainstream zoos and aquariums across the country.
Those improvements have brought a new challenge: higher numbers of age-related health problems in animals. To address those maladies, zoos and aquariums are leaning on human health care technology and tweaking traditional approaches. But the further animal care advances, the deeper zoos confront the ethical question of determining when to end an animal’s life.
“We’re not doing it to create longevity records,” Bill Zeigler, senior vice president of animal programs at Brookfield, said of improving care for animals. “We’re doing it because we’re trying to create the best care and welfare. It’s subtle, but it’s a big difference in how we approach things.”
Like medical care for humans, care for zoo and aquarium animals has improved steadily through decades of more useful technology, better medicine and growing bodies of research. And the relatively new maladies that zoo and aquarium veterinarians see resemble those seen by physicians treating people in their golden years.
Multiple maladies
In Ramar’s case, it was arthritis in his knees. Hiss Majesty was stricken late in life with a cancerous growth in a foot. Heidi is 14 years old and her teeth are deteriorating. Cardiovascular problems, osteoporosis, failing eyesight and kidney malfunction are other conditions elderly animals share with humans.
“If we have a lot of animals that are living longer, we need ways to care for them and also make sure we have enough space for newer animals,” said Lisa Faust, vice president of conservation and science at Lincoln Park Zoo, which is participating in a collection and analysis of species data to determine median life expectancy for all animals in zoos and aquariums. “It’s a balancing act.”
To reach the point of giving human medications to Ramar, Brookfield performed CT scans on the silverback gorilla to pinpoint specific joints that were giving him the most trouble, said Mike Adkesson, vice president of clinical medicine at Brookfield. Adkesson then compared Ramar’s scans with those of humans and spoke with the patients’ doctors to get a clearer sense of how much pain Ramar was experiencing.
“A lot of our animals end up on medications that are very similar to what you’d probably find in the drug cabinet of an older person in a nursing home,” Adkesson said.
In addition to giving Ramar Celebrex, zoo staff changed the position of hand holds in his exhibit to allow him to pull, relieving pressure on his knees. They also gave him a rolling stool to sit on, instead of squatting, and separated him from the rest of the group to eliminate other apes’ increased aggression toward Ramar, a typical response to older gorillas.
Heidi, the reindeer, is arthritic and is on a low dose of anti-inflammatory medication. Her more pressing issue is that she has lost a few teeth, prompting use of the water-softened hay. Keepers at Brookfield’s Hamill Family Wild Encounters, where Heidi is on display, also use fans and misters to keep her cool in hot weather, lead zookeeper Andy Schertz said.
Hiss Majesty, the lizard that Shedd said is at least 15 years old, developed a tumor in his right rear foot. Tumor and foot were removed in the middle of last year. He was fitted with a prosthesis made with a 3-D printer. Sometimes he wears his prosthetic and sometimes he doesn’t.
At Lincoln Park Zoo, one of its more prominent, geriatric residents has avoided surgery so far. Maku, a 30-year-old eastern black rhinoceros, receives joint-enhancing nutrients in a powder sprinkled on his fruit and vegetables, said Kathryn Gamble, the director of veterinary medicine at the zoo.
Planning for the future
On a broader scale, Lincoln Park’s Population Management Center is running the Survival Statistics Program, data collection and analysis aimed at finding species’ median life expectancy, with the aim of planning better care for animals as they approach later stages of life.
Finding the balance between caring for older animals and opening space for newer ones raises the issue of euthanizing animals, a topic that institutions are refining as animals’ health care advances.
A few weeks ago, Brookfield’s Adkesson and his team gave a presentation to zoo staff on euthanasia. The goal is to start having open, candid conversations about age-related conditions earlier in an animal’s life, and to make sure that discussion includes veterinarians, keepers, nutritionists and welfare assessment teams, Adkesson said.
Those delicate conversations on animals’ quality of life often involve whether they are interacting normally with other animals in their group and care staff, eating normally, maintaining proper weight or experiencing muscle wasting.
“Euthanasia is a difficult thing to process, and it’s a difficult thing to do,” Dr. Adkesson said. “But in many ways, it is a final act of kindness, and it is an ability to alleviate suffering and to let an animal end its life with dignity and some grace.”
He said staff at the zoo prefers never to euthanize an animal too late, not even by a day.