The Washington, D.C., zoo welcomed the "precious" newborn on Aug. 21
Baby Panda
Credit: Smithsonian National Zoo

This little baby panda is promptly plumping up!

On Friday, the Smithsonian's National Zoo offered an update on the 1-month-old panda cub who came into the world on Friday, Aug. 21. Able to conduct a brief exam after the tiny animal's mom Mei Xiang left the den for an early-morning "bite to eat," zookeepers measured the newborn's belly for the first time.

The cub weighed in at just under 3 lbs. and measured 13.9 inches from nose to tail tip, with its tail accounting for two of those inches.

"For the first time, we had a chance to measure the cub’s abdominal girth as well. It’s back and belly measured 32 centimeters, or 12.5 inches in circumference. Our plump panda cub is almost as round as it is long!" wrote Laurie Thompson, assistant curator of giant pandas, in a press release.

Thompson noted that the baby animal "relies on Mei Xiang’s milk for all of its nutritional needs," and that when it turns 1, it'll graduate to a diet of mostly bamboo and other solid foods. "However, it may nurse for comfort up to 18 months of age," the animal expert added.

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The zoo further explained that they will know the sex of the panda cub soon, once the Center for Conservation Genomics analyzes results from a cheek-swabbed DNA test taken Sept. 19.

When the zookeepers were able to examine the panda cub on Sept. 13, it weighed just under 1.5 lbs., meaning the cub almost doubled in size in slightly under two weeks.

"We are encouraged to see that our young panda appears to be healthy and vibrant," the zoo wrote of the cub at the time, calling it an "active and responsive newborn."

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As Mei Xiang, 22, gets more comfortable taking breaks away from her baby, the zoo's keepers will be able to perform longer check-ups. To keep up to date on all the recent panda cub happenings, you can check in on Mei Xiang and her cub on the National Zoo's Panda Cam.

In addition to her new cub, Mei Xiang is also mom to Tai Shan, 15, Bao Bao, 7, and Bei Bei, 5.

"Giant pandas are an international symbol of endangered wildlife and hope, and with the birth of this precious cub we are thrilled to offer the world a much needed moment of pure joy," Steve Monfort, the John and Adrienne Mars director of the Smithsonian’s National Zoo and Conservation Biology Institute, said in a statement around the time of the unnamed cub's birth.

In addition to her new cub, Mei Xiang is also mom to Tai Shan, 15, Bao Bao, 7, and Bei Bei, 5.