Calgary Zoo gorilla, Zuri, in critical condition

One of the Calgary Zoo's gorillas is in critical condition after undergoing emergency surgery, officials say.

The animal care team recently noticed changes in the appetite and activity level of the 19-year-old female western lowland gorilla, said Dr. Doug Whiteside, a senior staffveterinarian.

"She is still in critical condition," he said.

"She has made a little bit of a positive improvement in terms of overall responsiveness but she still has us quite worried."

Tests indicated the gorilla had a severe abdominal infection, prompting an emergency operation on Wednesday.

"She is on around-the-clock monitoring and she is getting multiple medications several times a day," Whiteside said.

He said it's difficult for all zoo staff, when an animal falls ill.

"It is very hard on us to see any of our animals ill and particularly with Zuri, she is a pretty special gorilla to us," he said.

The average life expectancy for a female gorilla in zoos is about 40 years of age.

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