National Zoo: Week-old panda cub who died had fluid in abdomen

National Zoo officials said Monday that preliminary necropsy results from the zoo's recently deceased panda cub show that the cub had fluid in its abdomen and some discoloration in the liver.

Chief Veterinarian Suzan Murray said the free fluid in the abdomen was abnormal for a cub. The cub — which was unnamed — weighed 100 grams, had nursed and had a coat that was "just beautiful," Murray said.

The cub is believed to have been a female, Murray said, since it seemed to be developing ovary-like tissue.

There was no evidence of external trauma to the cub, meaning that her death wasn't caused by a crush injury. But the color of the cub's liver gave zookeepers pause. "Typically, livers have a very uniform color," Murray said, but she was hesitant to blame the discoloration for the death."Nothing suggests in hindsight that we would do anything differently," said Zoo Director Dennis Kelly.

Full necropsy results should be back in two weeks, at which time Murray said the zoo would know definitively why the cub died.

Mei Xiang, the cub's mother, appears to still have a maternal instinct. "Sadly, we have witnessed her cradling an object for most of the night," Kelly said.

But Mei Xiang has left her den, and keepers were able to draw blood from her. Murray said preliminary test results are normal. Once she starts leaving the den more frequently, the National Zoo expects to reopen the Panda House.

The cub was born unexpectedly last Sunday, Sept. 16. The odds of Mei conceiving a cub after five consecutive pseudopregnancies since 2007 had been less than 10 percent, the zoo said last week.