This picture, taken on June 4, 2010 shows a 14-year-old male giant panda Kou Kou at the Oji Zoo in Kobe city, Hyogo prefecture, western Japan. Kou Kou has died after it was anesthetised for artificial insemination, a zoo official said.

A male giant panda in a Japanese zoo died after it was sedated so it could donate semen in an artificial insemination programme, a zoo official said Friday.

Kou Kou, or Xing Xing in Chinese, died Thursday of cardiac arrest after failing to recover from an at the Oji Zoo in the western port city of Kobe.

Veterinarians had sedated the 14-year-old animal as part of a programme to impregnate his partner Tan Tan, or Shuang Shuang in Chinese, also 14.

The zoo has set up a site for floral tributes and a message board.

Giant , a highly endangered species native to parts of China, are notoriously slow at reproducing in captivity.

The Kobe , after trying in vain to naturally mate the pair from 2003 to 2006, then began trying artificial insemination.

Tan Tan became pregnant in 2007 but the cub was stillborn. She had a live birth the following August, but the cub died three days later.