WASHINGTON (AP) -- The surviving panda cub at the National Zoo has more than doubled in size in the nearly two weeks since he was born.

Zoo officials say veterinarians were able to do a quick examination of the male cub on Wednesday when his mother, Mei Xiang (may SHONG), left her den. The cub weighed 10 ounces as of then. He was about 4 ounces at birth.

Mei Xiang gave birth to twin cubs on Aug. 22. The smaller of the two cubs died four days later. Mei Xiang stopped caring for the smaller cub, and zookeepers were bottle-feeding it.

The surviving cub appears to be healthy and developing normally. He's still pink in color, but his black markings are becoming visible. He has not yet opened his eyes, which is normal.