WASHINGTON - The Giant panda at the National Zoo has given birth to a panda cub, the zoo announced Friday.
The zoo tweeted that Mei Xiang's cub was born at 5:32 p.m.
Zoo officials say they heard the cub and saw it for a very brief time immediately following the birth.
"Mei Xiang picked the cub up immediately and began cradling and caring for it," officials say in a news release.
Staff on the panda team said during an evening press conference that Me Xiang is demonstrating classic mothering behavior and that the cub is making its presence known.
"The cub was born alive, we heard it squealing, it appears to be doing well," said Brandie Smith, giant pandas curator.
During the next five to six hours, the team will continue to keep a close eye on Mei Xiang, who could still deliver a second cub. There is a 50 percent chance that she is carrying a twin, said Dennis Kelly, director of the National Zoo.
The panda's team began preparing for the impending birth when her water broke around 3:36 p.m. Friday.
Veterinarians will examine the newborn cub within the next 48 hours and then every few days during the next week. They will check the cub's ears, heart, lungs and weight. A healthy cub should be between 90 and 110 grams.
During the health checks, the panda cam will be turned off, officials say.
If a second cub is born, zoo staff will care for one while Mei Xiang will care for the other, and then switch cubs the following day to ensure each cub gets the right amount of food, care and warmth.
Mei Xiang was artificially inseminated twice in March -- after failing to breed naturally.
Because she was artificially inseminated using semen from male panda, Tian Tian, and frozen semen from the San Diego Zoo's male giant panda, Gao Gao, officials will perform a paternity test to determine who sired the cub.
This is Mei Xiang's third cub born through artificial insemination.
Mei Xiang's second cub was born Sept. 16, 2012 but died six days later.
Her first cub, Tai Shan, was born July 9, 2005. He now lives at the Panda Base in BiFengzia in Ya'an, China.
The Giant Panda Habitat will remain closed until further notice to provide Mei Xiang and her cub some quiet.
The zoo will not name the new cub for at least 100 days because survival rates are so low for panda cubs, Kelly said.
"We're going to be tense for the next two to three months until we see that cub really thriving. So far it looks like a good-sized cub, it's vocalizing well. We have high hopes but we're not going to relax," he said.
Giant pandas are endangered and a new cub helps increase the species' chances for survival, zoo officials said.
Follow the updates with the Panda Cam. Kelly said viewers will be able to watch the pandas in 15-minute increments due to high traffic.
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