Pogo the gorilla found dead in her cage

San Francisco - Pogo, one of the world's oldest captive gorillas, died at the San Francisco zoo with a tummy full of grapes and her cherished baby ape doll close by.

The orphaned West Africa native was 48.

She was found dead on Wednesday in the heated sleeping chamber she shared with four other Western lowland gorillas.

The younger apes were observing her when zookeeper Mary Kerr, who worked with Pogo for nearly three decades, discovered the body, zoo spokesperson Alexander Winslow said on Thursday.

"They knew she had passed away," he said.

The 95kg primate had arthritis, heart disease and lower-back disc disease. A necropsy was scheduled on Thursday.

Born in Cameroon and raised by American missionaries and a nurse after her parents were killed for meat, she was donated to the San Francisco zoo in 1961 when she was three years old.

She did not have offspring but became known as a nurturing "aunt" to younger gorillas.

Visitors left magazines, calendars and even a television.

Pogo's remains will be donated to the University of California, Santa Cruz for anthropology research.

Gorillas can live 35 years or longer in the wild and longer than 50 years in captivity.

Some of the oldest include Philadelphia zoo's Massa, who lived to 54, and Rudy at the Erie zoo in Pennsylvania, who lived to 49. - Sapa-AP