WASHINGTON (AP) -- Jubilation over the recent birth of panda twins at the National Zoo turned to sadness Wednesday as one of the newborn cubs died after three and a half days.
The zoo's panda mom Mei Xiang gave birth to the first cub Saturday at 5:35 p.m. and a second cub about five hours later. Had both cubs survived, they would have been the 17-year-old panda's third and fourth surviving offspring.
Veterinarians did not immediately announce the cause of the smaller cub's death but said they would perform a necropsy, the equivalent of a human autopsy.
Nothing was obviously wrong with the cub that died, and the zoo doesn't know if it was born with problems, said Associate Director for Animal Care Sciences Brandie Smith. Despite its small size, the cub was still in the normal size range for cubs that have survived, she said.
Mei Xiang has two other surviving offspring. The first, Tai Shan, was born in 2005. Her second cub, Bao Bao, turned 2-years-old on Sunday. This isn't the first time that Mei Xiang has lost a cub. She gave birth to a stillborn cub in 2013, the same year she gave birth to Bao Bao. And in 2012, Mei Xiang gave birth to a cub that died after just six days. Its lungs hadn't fully developed.
The zoo said Tuesday afternoon, however, that Mei Xiang had gone almost 24 hours without allowing them to swap the cubs. As a result, animal keepers were taking a hands-on approach to caring for the smaller cub.
"We did know that would come with its own set of challenges," he said.
The zoo said the cub had "shown some signs" of regurgitating the liquids it was being fed, which could lead to the cub inhaling liquid into its lungs. Veterinarians gave the cub antibiotics to prevent a possible infection, the zoo said.
Neiffer, the veterinarian, said Mei Xiang never showed any signs she was concerned about the smaller cub.
The zoo said the mortality rate for pandas in their first year in human care is 26 percent for males and 20 percent for females. The zoo has not said whether the cub that died was male or female.
The National Zoo is one of only four zoos nationwide to have pandas, which are on loan from China.
The zoo's current pandas, Mei Xiang and Tian Tian, the parents of both Bao Bao and Tai Shan, arrived in 2000. The pandas belong to China as do any cubs they have. The pair's first cub, Tai Shan, returned to China in 2010. Their second cub, Bao Bao, still lives at the National Zoo.
Associated Press writer Jessica Gresko contributed to this report.
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