It's a boy? It's a girl?



Well, it's a panda cub! We weren't sure if we'd ever see this day again, but the National Zoo's female giant panda, Mei Xiang, gave birth to a panda cub Sunday night -- her second, following five pseudopregnancies in a row. Not to mention a whole lot of dashed hopes.

Yep, happy days are here again. The new cub was born at 10:46 p.m. Sunday. The zoo announced the news about four hours later.



In a press conference today, keepers said that we won't see much of the cub or its mom for a week or so. "She's not eating now, she's not drinking now, she's 100 percent focused on her baby," a zoo official said. As Mei Xiang gets more comfortable, she'll venture out for food and water and zoo keepers will be able to examine and determine the sex of the cub.

OK, but we need baby pics, and we need them now!



“I’m cautiously optimistic as we haven’t seen the cub yet, but we know that Mei is a good mother," said Dennis Kelly, director at the Smithsonian’s National Zoo, in a press release announcing the birth around 2:30 a.m. Monday. "Like everyone else, I’m glued to the panda cam for my first glimpse of the cub!”

Fine, fine.



Mei was artificially inseminated twice in April -- including once while zoo staff live-tweeted. (Talk about over-sharing!) Vets used sperm collected and frozen from Tian Tian in 2005. That might have been a particularly good year for him, as 2005 was also the year that brought us Mei Xiang and Tian Tian's first cub, Tai Shan.



"One factor that may have helped Mei Xiang conceive a cub was her return to a more normal estrus cycle," the zoo said. Mei went into estrus this year in late April. From 2009 to 2011, she went into estrus in January. However, Tai Shan was born in a year when Mei began her cycle early.



The odds of Mei conceiving a cub after five consecutive pseudopregnancies since 2007 were less than 10 percent, the release said.

Zoo vets hadn't detected a pregnancy via ultrasound leading up to the cub's birth, but they hadn't for Mei Xiang and Tian Tian's first cub, either.

Tai Shan -- dubbed Butterstick by D.C. panda fans, since he was the size of a stick of butter at birth -- was born July 9, 2005. He moved to China in 2010 to join a breeding program.



According to the zoo, keepers began to prepare for a birth again after they saw Mei "spending extended periods of time" licking and cradling toys.



As happened with the birth of Tai Shan, all our enjoyment of the new cub will be via the grainy panda cam for the time being. Vets won't examine the cub for a few weeks, to give Mei and the new baby time to bond.



Panda pregnancies can last for as wide a range as 90 to 160 days. The average is 135 days, which had given us a very rough due date of Sept. 10-12.



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