Artificial Insemination For National Zoo's Giant Panda
April 1, 2013

Female Giant Panda Artificially Inseminated In US As UK Pair Fail To Mate Over Weekend

redOrbit Staff & Wire Reports - Your Universe Online

Veterinarians at the National Zoo in Washington DC have artificially inseminated a female panda after detecting a rise in her urinary estrogen levels over the weekend, various media outlets have reported.

According to the Associated Press (AP), the procedure was performed on the zoo´s female giant panda, Mei Xiang, by a team of scientists on Saturday morning. The decision to artificially inseminate Mei Xiang was made after handlers concluded that no natural breeding between the female panda and her male partner, Tian Tian, had occurred overnight on Friday, the wire service added.

A combination of fresh and frozen semen belonging to Tian Tian was used in the procedure, Kate Jacobson of the Washington Examiner said. Mei Xiang has become pregnant twice after being artificially inseminated with Tian Tian´s sperm. One panda cub, Tai Shan, was born in 2005 and now lives in China. A second cub, a female, was born last September but died one week later due to lung and liver complications.

Dave Wildt, head of the Center for Species Survival at the Smithsonian Conservation Biology Institute, told Jacobson that experts are “hopeful” that their breeding efforts will be successful. He added that they are “encouraged by all the behaviors and hormonal data we've seen so far “¦ We have an extremely small window of opportunity to perform the procedures, which is why we monitor behavior and hormones so closely.”

Likewise, Richard Gray of The Telegraph reported on Sunday that the two pandas on loan to the Edinburgh Zoo also failed to mate over the Easter weekend. Experts had hoped that the hormone changes indicating that the female panda, Tian Tian, was ready and willing to breed would appear by Sunday morning.

Had Tian Tian and her male partner Yang Guang conceived, they would have produced the first panda cubs born in Scotland. However, due to the lack of the physical and behavioral changes that would have signified the beginning of her 36-hour breeding season, experts at the zoo now have to endure “a tense wait over the approaching weeks before the pair´s short annual breeding window draws to a close,” Gray said.

According to Iain Valentine, Director of Giant Pandas for the Royal Zoological Society of Scotland:

"It's an exciting time at Edinburgh Zoo and we hope to have some news to share soon. A combination of methods are used to predict when female pandas go into season, primarily hormone analysis and behavioural observation."

"Both pandas started to show breeding behaviours pretty early this year when compared to 2012, which is a sign that they're nice and settled in their home in Scotland. Tian Tian has shown hormone fluctuations a couple of times that suggested we were about to see a hormonal crossover that then tells us the 36 hour breeding window is 11 to 14 days away; this is all a pretty normal part of the journey."

"We're still to see this indicator and we wait in anticipation each day, however the giant panda breeding season peak is actually mid-April, sometimes lasting until early May - this is when the Washington giant panda went into season last year - so this is really only early days still. Tian Tian in particular over the last three years has varied anything up to a month from one year to the next in terms of when she´s come into season.”

The two pandas are on loan to the Edinburgh Zoo for one decade, and experts are hopeful that they will successfully mate and give birth to cubs while in the UK. This is the second attempt to get Yang Guang and Tian Tian to mate after failed efforts to get the pair to breed shortly after they arrived in Scotland last year.