WASHINGTON (AP, ABC7) - A preliminary necropsy of the National Zoo's baby panda cub turned up a series of preliminary abnormalities that may end up shedding light on why the tiny panda died suddenly on Sunday.
The panda cub, which was born to Mei Xiang late last weekend, passed away unexpectedly early Sunday morning.
Initial findings in the necropsy uncovered that portions of the small panda's liver were hardened and that there was an increased level of fluid in the bear's abdomen, something that is more typical of fully-grown adult pandas.
More complete results and findings will come after a more thorough examination of the panda. Those results are expected in about two weks, Zoo officials said.
The giant panda cub born a week ago at the National Zoo in Washington died Sunday morning, saddening zoo officials and visitors who had heralded its unexpected arrival.
The 4-ounce cub, about the size of a stick of butter, showed no obvious signs of distress and made its final recorded noise shortly before 9 a.m. Sunday, zoo officials said at a news conference. Zoo officials say that Mei appeared to be mothering her cub very well; there were no signs of internal or external trauma on the cub when she was found.
National Zoo chief veterinarian Suzan Murray said Monday morning that they believe, based on an initial examination, that the panda cub was a female and had been nursing to some extent. Her coat was "beautiful", Murray said, and she also warned that these initial test results are very preliminary.
"Judging too much on the original necropsy can be dangerous at times," she said. "Something that might appear abnormal might be indeed normal under the microscope."
The cub's mother, Mei Xiang, then made an unusual honking sound at 9:17 a.m. that her keepers interpreted as a distress call, and she moved away from where she had been nesting with the cub. About an hour later, one keeper distracted her with honey water while another used an instrument similar to a lacrosse stick to pick up the cub.
The cub, whose gender could not be determined initially, was not breathing and its heart had stopped. A veterinarian attempted CPR before it was pronounced dead at 10:28 a.m.
"This is devastating for all of us here," National Zoo director Dennis Kelly said at a news conference. "It's hard to describe how much passion and energy and thought and care has gone into this."
Four American zoos have pandas, but Washington's pandas are treated like royalty. The zoo was given its first set of pandas in 1972 as a gift from China to commemorate President Richard Nixon's historic visit to the country.
Murray said that Zoo officials and their colleagues in China have been in constant communication since the cub's death. She said that the Chinese veterinarians have been extremely supportive.
"Our Chinese colleagues have been just wonderful," she said. "It has been a very collaborative approach."
Mei Xiang's first cub, Tai Shan, born in 2005, enjoyed enormous popularity before he was returned to China in 2010. Officials say that Mei is moving around well and expected to "return to her normal, wonderful giant panda self" in due time. Until then, though, the Panda House will remain closed until she is out of her den and acting normally.
The new cub, born Sept. 16, had been a surprise at the zoo. Fourteen-year-old Mei Xiang had five failed pregnancies before giving birth.
Panda cubs are especially delicate and vulnerable to infection and other illness. The first weeks of life are critical for the cubs as mothers have to make sure they stay warm and get enough to eat.
Panda mothers are about 1,000 times heavier than their cubs, and sometimes they accidentally crush them. On any given day in the first two weeks of life, cubs have a mortality rate of 17 to 18 percent, zoo officials said.
The cub showed no external signs of trauma in the immediate aftermath of her death, Murray said Sunday.
"The cub was just beautiful. Beautiful little body, beautiful face, with markings just beginning to show around the eye," Murray said.
As they did after Tai Shan was born, keepers had been leaving Mei Xiang alone with her offspring, monitoring her on video feeds that were also streamed on the zoo's website. Mei Xiang was resting comfortably after the cub's death, officials said.
The zoo's first panda couple, Ling Ling and Hsing Hsing, had five cubs during the 1980s, but none lived more than a few days. One of the cubs was stillborn; two others died of pneumonia within a day; another died from lack of oxygen after birth; and the final cub died of an infection after four days.
Atlanta has had three cubs, and the San Diego zoo has had six, including a cub born this year. A panda couple in Memphis has yet to have a cub, despite several tries.
The cub had not yet been named in accordance with Chinese tradition - it was to receive a name after 100 days on Dec. 24. Had the cub survived until then, it would have been roughly the size of a loaf of bread and weighed around 10 pounds. It will not be named posthumously, Kelly said.
Kelly said it was too soon to know if the zoo would attempt to breed Mei Xiang again. She was artificially inseminated with sperm from the zoo's male panda, Tian Tian.
"These bears are so critically endangered that every panda cub is important," Kelly said.
The panda exhibit was closed indefinitely. Early Sunday afternoon, there was still a sign outside the panda house announcing the cub's birth, and many visitors were unaware of the death.
At the zoo's panda-themed gift shop, Diana Salguero, 24, of Manassas, Va., was trying on a headband with panda ears when she learned from a reporter about the cub's death.
"I want to cry right now," she said. "I'm heartbroken. I've been excited all week. That's why I came out today."