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BERLIN, Germany - The staff at Zoo Berlin are keeping their famous twin panda cubs topped up with extra milk.
Panda mothers usually only raise one cub. So staffers are bottle-feeding the extra milk to the cubs once a day to ensure their healthy development, according to the zoo.
The twins, Meng Xiang and Meng Yuan (nicknamed Pit and Paule, respectively), are now five months old and weigh about 24 pounds each, the zoo said.
More than 35,000 people have visited the panda cubs since they made their public debut at the end of January.
The giant panda (Ailuropoda melanoleuca) is native to the bamboo forests in the mountains of central China where an estimated 500 to 1,000 adult pandas remain. The International Union for Conservation of Nature's Red List considers the species "vulnerable."
Adults feed almost entirely on bamboo and have to eat as much as 80 pounds a day to survive, according to the World Wildlife Fund.
A staff member at Zoo Berlin bottle feeds a panda cub. (Zoo Berlin via Storyful)
A staff member at Zoo Berlin bottle feeds a panda cub. (Zoo Berlin via Storyful)
A staff member at Zoo Berlin bottle feeds a panda cub. (Zoo Berlin via Storyful)