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. It’s caused by a a tumor that secretes a hormone that controls the level of calcium in her body. In such cases, surgery is not an option.

As the tumor grew, medication and treatment efforts from the zoo became less effective. Her condition declined significantly over the last few days, and after consulting with experts, the zoo decided to put her down.

“All who knew and loved Donna will miss her greatly,” said Regina Mossotti, Vice President of Animal Care, Saint Louis Zoo. “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 years. 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.

Donna is the second Asian elephant the zoo has lost this year, following the loss of another longtime friend in Rani last month.