San Diego Zoo's male giant panda, Gao Gao, goes to town on his birthday cake on Jan 21, 2009 in San Diego, California, US. [Photo/IC]

CHENGDU -- A Chinese panda expert on Tuesday expressed concern for a giant panda at California's San Diego Zoo which was reported to be suffering from heart disease after a physical examination.

Gao Gao is 26, old for a Panda, said Wang Chengdong, director of the veterinary hospital at the China Conservation and Research Center for the Giant Panda in southwest China's Sichuan Province.

Wang said he saw Gao Gao at the zoo last September when he was in good physical condition with a good appetite at that time, Wang said.

When giant pandas become older, they are prone to age-related disease," Wang said. As Gao Gao is old, it is hard to cure his heart disease. Medicine and rest are indispensable, according to Wang.

Pandas in China rarely suffer heart disease, Wang said.

"Gao Gao is too old to have an operation so we suggest he receive conservative treatment instead," Wang said.

Gao Gao was found in a nature reserve in Sichuan in April 1993 when he was a cub. He was separated from his mother and had suffered serious injuries.

Panda researchers saved him and took him to the center. He was sent to the United States in January 2003 as part of a 12-year research cooperation program between the two nations.

Wild giant pandas' life span is usually 15 to 20 years while the life span of captive pandas can reach 30 years.