A panda at Washington's National Zoo that has been tending to her squealing newborn cub also gave birth to a stillborn cub Saturday that wasn't fully formed and was never alive outside the womb, a zoo official said.
Mei Xiang gave birth to the motionless cub Saturday night after giving birth to its live twin the night before, zoo spokeswoman Pamela Baker-Masson said. The mother groomed her stillborn cub for 17 minutes before letting it fall to the floor, she said.
Mom still hasn't let zoo staffers get close enough to get a good look at her live cub, but it was squealing throughout and appears to be doing well, Baker-Masson said.
The zoo began performing a necropsy on the stillborn cub late Saturday that they hope will tell them why the cub stopped developing and died in-utero, she said.
When caretakers do get to check out the live cub, which is the size of a stick of butter, they will try to listen to its heart and lungs, record its weight and collect a DNA sample.
Brandie Smith, the zoo's curator of mammals, said she and others are "cautiously optimistic" about that cub's health. She compared the planned exam to a race car pit stop, a fast and highly choreographed checkup before reuniting mom and cub.
The live cub was the 15-year-old panda's third. Mei Xiang gave birth to a cub last year that died after just six days. Its lungs hadn't fully developed and likely weren't sending enough oxygen to its liver. Mei Xiang's first cub, a male named Tai Shan, was born in 2005.
An early exam at the zoo is a change from last year, and staff members made several other changes in preparation for another cub. Mei Xiang's den was altered to allow keepers to get closer to her, and the zoo invited a panda expert from China who specializes in newborns to help out. Two of the zoo's panda keepers also recently spent time in China learning more about examining newborns.
Zookeepers made two attempts at examining the cub Saturday, but Mei Xiang was cradling the cub and officials were unable to take it for a closer examination, zoo spokeswoman Baker-Masson said. They planned to try again Sunday.
Information collected during the exam will serve as a baseline for future exams. And the DNA sample, either from a swab of the cub's mouth or feces, will be used to determine the cub's father. Mei Xiang was artificially inseminated both with sperm from the zoo's male panda, Tian Tian, and sperm from a panda at the San Diego Zoo, Gao Gao.
Associated Press writer Tim Jacobs in Chicago contributed to this report.
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