Cookie the Lionness was euthanized at the age of 23 after a "cancerous condition" resulted in her declining condition, the Los Angeles Zoo said.
The Los Angeles Zoo’s 23-year-old lioness, Cookie, was euthanized Friday after spending a month in veterinary care, the zoo announced.
"Her quality of life had diminished and zoo staff made the difficult decision to euthanize her," the zoo said in a statement released Friday. "Initial necropsy results indicate that Cookie had a cancerous condition resulting in her declining condition."
Cookie came to the LA Zoo in 1997 from the Wildlife Waystation located in the Angeles National Forest. She arrived with her companion Lionel, who died in April 2011. Lionel was also 23 years old.
In 2008, Cookie developed a heart condition called cardiac tamponade in which fluid builds up in a sac around her heart preventing it from effectively pumping blood to the rest of her body.
Veterinarians at the LA Zoo, in consultation with physicians from UCLA and other vets, elected to surgically remove a piece of the sac so the fluid around Cookie’s heart could drain out.
"To our knowledge, this was the first time this procedure has been performed in a lion although it is a relatively common procedure in dogs and cats," the zoo said. "She recovered beautifully after surgery and had no complications."
Zoo officials say Cookie’s age is a "testament to the excellent care she received at the Zoo," adding that lions typically live longer in zoos than in the wild because they do not need to compete with other species for resources.
"Cookie was an animal that zoo-goers enjoyed watching. She will be remembered by zoo visitors and staff alike," the zoo said.