TULSA, Oklahoma - The necropsy performed on the elephant that was euthanized on Sunday revealed she had a 10-pound bladder stone, according to the Tulsa Zoo.

The zoo said Tova the 43-year-old Asian elephant was euthanized because she had stopped eating and drinking and was in pain. Experts from the Center for Elephant Conservation tried to find what caused the symptoms. Despite that, Tova was euthanized to end her suffering.

During the necropsy, a nearly 10-pound bladder stone was found to be completely obstructing the flow of urine from the elephant’s bladder, according to a news release from the zoo.

Bladder stones are hard masses of minerals found in the bladder that can affect humans or any animal. In Tova’s case, the stone was irritating the bladder wall, which would explain her abdominal discomfort. When the stone completely blocked the bladder from emptying, Tova's symptoms worsened and caused her to stop eating and drinking, as well as stopped her ability to urinate.

There are ways to remove or break up bladder stones in people and some animals. In elephants the identification of stones is very difficult due to the animal’s size and anatomy, the zoo said. Removal is also typically not possible for the same reasons, as was the case with Tova, the zoo said.

“No animal health or care professional takes lightly the decision to humanely euthanize any animal. While saddened by Tova’s loss, all parties are comforted knowing we made the right decision for Tova,” says Joe Barkowski, Vice President of Animal Conservation and Science at the Tulsa Zoo. “The results indicate the condition was long-term, had advanced to a stage that had begun to cause her great pain and discomfort, and could not be resolved, so humane euthanasia was the only viable option to end her suffering.”

Zoo staff observed initial signs of discomfort in Tova on November 9 and teams worked around the clock to understand and identify the source of her symptoms. Colleagues from the Center for Elephant Conservation also came to consult with zoo experts to ensure all avenues for treatment were explored.

Tova’s health rapidly declined early Sunday and veterinarians and other experts determined it was best to end her suffering through humane euthanasia.

The zoo conducted a necropsy to assess Tova’s health, body condition and any visible abnormalities or concerns at time of death. 

Tova, and fellow Asian elephant, Asha, arrived at the Tulsa Zoo on September 28 from the Ringling Bros. and Barnum & Bailey Center for Elephant Conservation in Florida.

In addition to Asha, the Tulsa Zoo is home to Asian elephants, Gunda, Sooky and Sneezy.