The National Zoo's week-old giant panda cub died of unknown causes this morning.
Zoo officials say the cub was found dead after panda keepers heard sounds of distress from its mother, Mei Xiang.
MORE: Panda cub seen at National Zoo
Veterinarians
retrieved the cub for an evaluation about an hour later and immediately
performed CPR and other lifesaving measures, the zoo said.
"Sadly
the cub was unresponsive," the zoo said. The cub weighed just less than
100 grams and showed no outward signs of trauma or infection.
MORE: Giant panda gives birth to cub at National Zoo
"We are brokenhearted to share that we have lost our little giant panda cub," the zoo said.
Panda
experts have said the first weeks of life are critical for the panda
cubs as mothers have to make sure they stay warm and get enough to eat.
"It's
kind of a nerve-racking period for the folks that are monitoring mom
and cub," Rebecca Snyder, the curator of mammals at Atlanta's zoo, said
last week. Atlanta is one of only two other American zoos to have had
cubs.
Panda cubs are born about the size of a
stick of butter and are delicate infants. Panda mothers are about 1,000
times heavier than their cubs, which are born with their eyes closed.
The delicate cubs have died in the past when accidentally crushed by
mom. That happened in two different zoos in China in 2009 and 2010 when
mothers killed their young while attempting to nurse.
The National Zoo's cub was the second born to giant pandas Mei Xiang and Tian Tian as the result of artificial insemination.
Mei
Xiang has had five consecutive false pregnancies since 2007 and had a
less than 10% chance of being pregnant after so many failed attempts.
The
cub was born at 10:46 p.m. Sept. 16. Vets at the National Zoo observed
Mei Xiang and her cub on a Web cam and had not touched the cub until
today, so the mother would raise her cub naturally.
Chief
veterinarian Suzan Murray said last week that Mei Xiang was behaving
exactly as she had when her first cub, Tai Shan, was born.
"She
is cradling her cub closely, and she looks so tired, but every time she
tries to lay down, the cub squawks and she sits right up and cradles
the cub more closely," Murray said. "She is the poster child for a
perfect panda mom."
Officials were following a
Chinese custom to wait 100 days before naming the cub. Had the cub
survived, it would have been named Dec. 24. At 100 days old, it would
have been roughly the size of a loaf of bread and weighed about 10
pounds.