Pathologists at the Smithsonian's National Zoo performed a necropsy (animal autopsy) Sept. 23 on the six-day-old giant panda cub that died earlier that morning. A final pathology report will provide more information in the next few weeks, but the preliminary report suggests two potential abnormalities: moderate levels of fluid in the cub's abdomen and an area of hardness in the liver. The significance of these findings is not yet clear. The veterinary and pathology team will continue to work closely during the ongoing histological evaluation.
The giant panda cub born Sept. 16 appeared to be female. At the time of death, she weighed a little less than 100 grams, about four ounces. There were no signs of trauma, external or internal, her heart and lungs appeared healthy and normal, and a small amount of milk was found in the cub's gastrointestinal tract, which suggests that she nursed. The mortality rate for pandas in their first year of age in human care is 26 percent for males and 20 percent for females. Note that some early mortality rates may be underestimated.
The panda team continues to monitor the cub's mother Mei Xiang via the Panda Cam. She appeared to sleep well last night. Watchers noticed her cradling an object, as she did before to the birth of the cub. Scientists and keepers believe this is an expression of her natural mothering instinct.
Mei Xiang is moving around this morning, and the panda team was able to weigh her. She weighs 217 pounds, which is less than her regular weight but normal for a mother who has not eaten (Mei Xiang had not left her den in more than a week). She ate most of her normal diet (some bamboo, fruit and biscuits) and drank some water this morning, and Zoo veterinarians took a blood sample and a vaginal culture to confirm the state of her health. Zoo staff fully anticipate that she will return to her normal behaviors soon. Once this happens, visitors will be able to enter the David M. Rubenstein Giant Panda Habitat.
The Zoo will continue to work closely with Chinese colleagues and share the information it has learned about giant panda reproduction and cub health. No decisions will be made about Mei Xiang and Tian Tian's future at the National Zoo until Mei Xiang's behavior returns to normal.
The Panda Cam, sponsored by Ford Motor Company Fund, will remain on so panda enthusiasts around the world can continue to watch Mei Xiang and Tian Tian.