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The heaviest panda cub in the history of China's artificial reproduction program was born in southwest China Monday morning after its mother was in labor for some 34 hours, an official with the China Wolong Giant Panda Protection and Research Center confirmed.

The male cub was born at 10:39 AM at the center and weighed 218 grams, said the center's head Zhang Hemin. "It's the second cub born this year at the center," he said.

It was the first birth for the cub's mother, Zhang Ka, who was born in the wild six years ago. The delivery set a record for being the longest, said Zhang.

According to the center, Zhang Ka went into heat in early March and she mated. Experts also performed artificial insemination to ensure conception.

At 2:30 PM on Friday, Zhang Ka appeared to go into labor. Experts at Wolong began a 24-hour watch. Just before 1 AM Sunday, the expectant mum's waters broke, but exhausted she failed to deliver her cub.

By early Monday morning experts decided to prepare to perform a Caesarean section but just a minute before the anesthetic was to be administered a tiny noise was heard and the little pink creature was born. The delivery room was filled with the cheers and applause of staff.

According to statistics from the China Giant Panda Breeding Technology Committee since the first panda cub was born in Beijing Zoo in 1963, most of those born in captivity weighed between 83 and 190 grams. A cub of over 200-gram cub was very rare.

China started to artificially inseminate giant pandas in the 1960's but very few successful cases were reported. However, major breakthroughs began in the 1990s. Artificial insemination produced nine baby pandas in 2000, 12 in 2001, 10 in 2002 and 15 in 2003. Giant pandas show little instinctive behavior in captivity especially in regard to sexual desires.

Forestry authority statistics show fewer than 10 percent of male giant pandas mate naturally and fewer than 30 percent of females conceive normally. Female pandas become sexually mature at age four or five and have only one chance of pregnancy each year. After a gestation period of 160 days they deliver one or two cubs.

Figures from the State Forestry Administration show there are over 180 giant pandas living in captivity on the Chinese mainland.

Experts had previously estimated there were 1,590 giant pandas living in the wild in China but Chinese and British scientists announced in June there could be as many as 3,000 after a survey using a new method to profile DNA from giant panda feces.

(Xinhua News Agency August 8, 2006)