By CBSLA Staff

LOS ANGELES (CBSLA) — A 12-year-old Masai giraffe has died hours after delivering a full-term stillborn calf, the Los Angeles Zoo announced Tuesday.

Hasina, 12, was pregnant with her sixth calf, but due to the abnormal breech position, a natural delivery was not possible, zoo officials said. A team of more than 30 of the zoo’s Animal Care and Animal Health staff worked for five hours starting on Monday morning to remove the unborn calf and save Hasina’s life.

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The procedure was successful and Hasina recovered from the anesthesia, was standing on her own, and appeared to be doing well – but zoo officials say she died Monday night.

(credit: Los Angeles Zoo)

“Hasina was a healthy giraffe in her prime, so we were hopeful that she would survive,” Dr. Dominique Keller, the zoo’s chief veterinarian and director of animal health and wellness, said in a statement. “There were many complicating factors at work in this procedure such as the difficult position of the breech calf and the length of time under anesthesia.”

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Hasina came to Los Angeles from the San Diego Zoo in March 2010 and sired three calves with 9-year-old Phillip.

“We were all focused on the welfare of Hasina who has been with us for years,” Beth Schaefer, director of the zoo’s animal programs, said in a statement. “Hasina has always been a favorite among staff and guests, and she will be greatly missed.”

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Giraffes are the tallest land mammal, and Masai giraffes can grow to a height of 17 feet and a weight of 2,700 pounds. They are found in Kenya and northern Tanzania, and are considered an endangered species.