Gao Gao, a 33-year-old male giant panda, died on Monday, the China Conservation and Research Center for the Giant Panda in Sichuan province, announced on Thursday.

Gao Gao was rescued from the wild in Baoxing county, Sichuan, on April 6, 1993. It is estimated that he was born in September 1992.

In 2003, Gao Gao, as a member of the China-US "12-Year Giant Panda Breeding Program", arrived at the San Diego Zoo in the United States. During his stay, he bred five cubs.

On Nov 1, 2018, he returned to the center in Sichuan. Suffering from age-related conditions such as hypertension, heart disease and arthritis, he received close attention and meticulous care at the center, according to a post on the center's official WeChat account.

On Saturday morning, staff members observed that Gao Gao had a poor appetite and was lethargic, with noticeable abdominal bloating. His condition improved slightly after medication, the center said.

On Sunday, examinations revealed varying degrees of lesions in his right lung and other organs, for which he received immediate treatment. After treatment, he returned to his enclosure in stable condition and consumed liquid food.

On Monday morning, Gao Gao suddenly experienced symptoms including hind limb weakness, difficulty standing, and breathing. Despite all efforts to save him, he died that afternoon.