SACRAMENTO, Calif. (AP) -- A Sumatran tiger successfully underwent surgery at the Sacramento Zoo on Tuesday to remove obstructions caused by stones in its urinary tract.
The big cat, which was also diagnosed with cancer earlier this year, was out of surgery and awakening in its den at about 2:30 p.m., zoo officials and doctors said.
Surgeons from the University of California, Davis, School of Veterinary Medicine and the zoo began preparing the animal for the minimally invasive procedure in the early morning. The cat was anesthetized in its den at the zoo before being transported to the surgical suite. Doctors then implanted a thin, flexible tube to allow urine to drain normally from its right kidney to its bladder. The surgery itself lasted two hours, but a series of medical tests took another 3 ½ to 4 hours.
Harrison Edell, general curator of the Sacramento Zoo, said in a telephone interview that zoo officials were upbeat about the tiger's chances for recovery.
"Tonight he'll likely stay indoors," Edell said, but "in theory, he should be back to a semi-normal routine tomorrow afternoon."
He added: "We're on the road to recovery."
The 15-year-old male tiger named Castro is from Sumatra, an island in western Indonesia. It has been at the Sacramento Zoo since 1999. In the wild, Sumatran tigers typically live between 10 and 15 years.
It is one of about 200 Sumatran tigers in zoos around the world. Fewer than 500 are believed to live in the wild.
Edell said that doctors faced several challenges because of the cat's old age and other medical problems. Castro is also undergoing chemotherapy for lymphoma, a type of cancer.
"A lot of these medical issues are sort of related to one another," he said.
Doctors and other zoo officials said tests indicated Castro seemed to be responding well to cancer treatment.
The cat's spleen is back to a much smaller size, its white blood cell count is up, and its anemia is resolved, zoo officials and doctors said.
No further surgeries should be needed, said Bill Culp, a surgeon and interventional radiologist who helped perform the operation.
"He should be all set now," Culp said.
Castro has fathered five offspring, including CJ, born in March at the Sacramento Zoo. Its first granddaughter, Jillian, was born in February at the San Francisco Zoo.
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