The National Zoo in Washington is hoping to get its giant panda Mei Xiang pregnant this spring after taking delivery of frozen panda semen from China for the first time.

Caitlin Burrell of the Smithsonian Conservation Biology Institute returned to the US capital on Sunday with semen that had been stored at the Bifengxia Giant Panda Base in southwest China.  

The semen was drawn for a nine-year-old giant panda in China named Hui Hui that has yet to sire any cubs, the National Zoo said in a statement Tuesday.

It's famously difficult for pandas in captivity to get pregnant, but the zoo hopes to inseminate Mei Xiang when she goes into estrus for 24 to 72 hours in the coming weeks.

"Scientists are working to preserve 90 percent of the genetic diversity of the giant pandas living in human care for the next 200 years," the zoo said.

"There are currently 392 giant pandas living in human care; scientists hope to grow the population to 500 bears."

Mei Xiang has already given birth to two surviving cubs fathered by Tian Tian, the National Zoo's only male giant panda attraction.

This time around, however, the zoo said a cub sired by Hui Hui "would be more genetically valuable," based on a calculation of the best genetic matches for all the world's eligible breeding pandas.

Mei Xiang made international headlines in August 2013 when she gave birth to Bao Bao, who now lives separately from her mother at the zoo.

Bao Bao is set to go to China when she turns four years old, following in the footsteps of her older sibling Tai Shan, born in July 2005.

About 1,864 giant pandas live in the wild, according to the latest figures from China's State Forestry Administration, released in February.
Source: AFP