ST. LOUIS – Donna, an elderly Asian elephant at the Saint Louis Zoo, died Thursday morning after a recent tumor diagnosis.

Zoo officials say Donna was “humanely euthanized … due to a rapid and irreversible worsening of her health over the last several days.”

Last month, the zoo announced Donna was diagnosed with a condition known as primary hyperparathyroidism.

“That releases a hormone that increases the amount of calcium to the bloodstream, and changes in the body start to happen,” Michael Macek, director of the Saint Louis Zoo, said. “We were managing that with medication, but we knew as the tumor grew and was inoperable that the condition would get worse. We were watching closely, knowing the end was near.”

Donna’s condition declined significantly over the last few days, and, after consulting with experts, the zoo made the decision to put her down.

“All who knew and loved Donna will miss her greatly,” Regina Mossotti, the zoo’s vice president of animal care, said. “Our dedicated and expert Animal Care team did everything in their power to make sure Donna was comfortable as they managed her end-of-life care. While we grieve her loss, we’re grateful for the many memories she gave us and the public in her decades at the Zoo. We ask for the community’s thoughts and support during this difficult time.” 

Donna was 52. The median life expectancy for Asian elephant females under human care is 47.5 years old. She joined the Saint Louis Zoo at a very young age in 1971 and moved into the River’s Edge in 2001, becoming one of nine elephants at the zoo.

If it’s true that an elephant never forgets, then the last month will be significant for the herd.

Donna is the second Asian elephant the zoo has lost this year, following the loss of another longtime friend, Rani, on Oct. 13.

Macek said elephants are very social and, in an important part of the end of life, the elephants at the zoo were given time to grieve over Donna.

“We gave them several hours to come in and say goodbye,” Macek said. “They come in and will touch and smell and will often put their trunks to the other elephant’s trunks to see if there’s any breath there. Usually a couple hours. And then they’ll start to wander away. They’ve said their goodbyes.”