Gorilla caregivers face familiar questions about aging

This month, while the patient lay on the operating table under anesthesia, a cardiologist made a half-inch incision in the skin of his chest. She removed a small implantable heart monitor with a failed battery and inserted a new one.

Like many older men, the patient had been diagnosed with heart disease. The monitor will provide continuous data on heart rate and rhythm, alerting doctors to abnormalities.

Neat four stitches are needed to close the incision. In a few hours, the patient, a gorilla named Winston, will be reunited with his family in his habitat at the San Diego Zoo Safari Park.

Dr. Matt Kinney, a senior veterinarian with the San Diego Zoo Wildlife Alliance who led the medical team through the surgery, said Winston, 51, is a very old male gorilla. With improved health care, new technology and better nutrition, we’re seeing animals live longer and they’re healthier, he said.

In captive care (the term captivity is no longer popular in zoos), gorillas can live up to 20 years longer than the 30 to 40 years typically seen in the wild, and longer than zoo gorillas have lived in past decades. long.

However, like its human relatives, aging brings with it chronic conditions that require detection, diagnosis, and treatment. Gorillas are prone to heart disease, which is a leading cause of death for them and us humans.

So now Winston’s caregivers face questions similar to those faced by doctors and elderly patients: How much treatment is too much? What is the trade-off between longevity and quality of life?

Dr. Paul Kahler, chief veterinarian for the Wildlife Conservation Society of the Bronx Zoo, said caring for older wild animals is becoming increasingly complex. People’s medical and surgical knowledge can be directly applied.

It looks more like human geriatric care. To keep gorillas healthy, zoo veterinarians turn not only to techniques and medications developed for humans, but also consult with medical experts such as cardiologists, radiologists, obstetricians and dentists.

For example, Winston takes four common heart medications that people also take, albeit at different doses. (He weighed 451 pounds.) The heart monitor he received, smaller than a flash drive, was also implanted. Winston received his annual flu shot this fall and is undergoing physical therapy for arthritis.

“We hope to provide comfort to these animals in their later years,” Dr. Kinney said.

It doesn’t come cheap: When Winston received his new monitor, there were nearly 20 doctors, technicians and other staff in the operating room. But the San Diego Zoo Wildlife Alliance, the parent organization of zoos and wildlife parks, pays for Winston’s care through its annual operating budget. Donors and partners offset some of the additional costs.

Dr. Kinney points out that none of our animals are insured and they never pay the bills.

Several of Winston’s long-term caregivers, known as wildlife care experts, have retired. But as he has grown older, Winston has achieved the status of a silverback gorilla, and he remains at his post, managing his troop of five gorillas, keeping the peace and intervening in squabbles when needed.

Jim Hagwood, curator of mammals at the San Diego Zoo Safari Park, said he was a very gentle silverback gorilla and a very tolerant father. His youngest daughter also allowed her to take food from his mouth.

The zoo twice introduced females with sons into the group, which in the wild could lead to infanticide. But Winston’s caregivers believed he would accept it, and he did.

Hagwood said he raised the males as if they were his own sons. (Once they turn into rambunctious teenagers, however, they are relocated to their own habitat, a choice that human parents occasionally envy.)

Winston is a western lowland gorilla native to Central Africa who came to the San Diego Zoo in 1984. Dr. Kinney, who arranged Winston’s first ultrasound heart exam, said he was in good health until 2017, when his caregivers noticed a general slowdown in his condition.

Dr. Kinney said the tests showed only subtle changes and nothing alarming. Everyone breathed a sigh of relief. Normal aging.

Then in 2021, the entire force became infected with the coronavirus, possibly spread by humans. As with human patients, age matters.

Dr. Kinney said Winston was the most affected. He had a cough, severe lethargy, and loss of appetite. He started holding on to objects while walking.

After an infusion of monoclonal antibodies, Winston recovered. Currently, the entire team has been vaccinated and strengthened against the virus.

But while Winston was being treated, other tests by veterinarians and human doctors revealed health problems. Winston’s heart began to beat less efficiently; this resulted in him taking daily blood pressure and heart disease medication hidden in food, and having a monitor implanted. He also takes ibuprofen and acetaminophen to treat arthritis in his spine, hips and shoulders.

Even more worryingly, a CT scan and biopsy revealed a cancerous tumor lesion on Winston’s right kidney. This triggers a risk-versus-benefit conversation that should inform decisions about invasive treatments in older patients, but which is often skipped in humans.

Are we going to have surgery? Dr. Kinney recalled being confused. Most worryingly, what will recovery look like? He said after taking into account Winston’s age and life expectancy and determining that the tumor was not growing, we felt comfortable continuing to monitor him.

“Right now, we’re in a good balance,” he said. Mr Hagwood said it was not entirely a medical issue but reflected Winston’s ability to lead his troop, which includes a female named Kami, with whom he has had a fiercely loyal relationship for 25 years. Partnerships.

Some aspects of healthy aging may be easier to achieve for zoo primates than for humans. Their breeders only offer healthy options. They don’t smoke, said Marietta Danforth, director of the Detroit Zoo’s great ape heart program. They don’t eat cheeseburgers.

Winston’s vegetarian diet consists mainly of twig and root vegetables. The half-acre gorilla forest where he lives has hills, ponds and climbing structures to promote exercise.

Nonetheless, elder care necessarily involves end-of-life decisions. Winston may one day die of natural causes like Ozzie, a gorilla who died at Zoo Atlanta two years ago at age 61, and Khloe who died at age 60 at the Columbus Zoo in Ohio in 2017 .

But if his quality of life declines, if he stops interacting with the troops and his caregivers or begins to suffer, then human care ends. Even in California, where medical assistance in dying is included in the law, euthanasia remains illegal for humans. This is a choice made by Winston.

Dr. Kinney said this is a privilege of veterinary medicine. It also comes with great responsibility.

Dr Kinney said if Winston’s doctors, experts and carers had concluded after extensive discussions that a painless death was preferable to a shortened life, it would have been a very uneventful process. He said cardiorespiratory arrest can occur within minutes of an overdose of narcotics.

Dr. Danforth said there are about 350 gorillas and 930 great apes, including bonobos, orangutans and chimpanzees, in U.S. zoos. No matter how well they are cared for, some animal rights activists and primatologists believe they do not belong in zoos.

But even PETA, whose stance is that wild animals belong in the wild, acknowledged in an email that zoos like San Diego’s, which are accredited by the Association of Zoos and Aquariums, meet high standards for animal care.

Dr. Kinney said Winston had lived quality years. Gorillas have also become beloved media figures. Santiago will mourn his loss wherever and whenever he goes.

“Right now, we want to make sure that Winston has a good life and that he’s content,” Dr. Kinney said. We know a lot about what makes Winston Winston.