Twin Panda Cubs Born at National Zoo Appear Healthy and Strong

The cubs were born within a few hours of each other.

The cubs were born a few hours apart Saturday, said Dr. Don Neiffer, a veterinarian at the National Zoo. He said zookeepers won't be certain of the twins' chances of survival until both cubs begin walking.

One cub, believed to be the second-born, weighed in at 132.4 grams, said Neiffer. The second cub is smaller, weighing 86.3 grams, but appeared strong, he said.

Veterinarians were "ecstatic that things are going great," added Neiffer.

For now, the cubs will alternate spending time with Mei Xiang. When away from its mother, the other cub will be monitored in an incubator.

Almost exactly two years before the birth of her twins, Mei Xiang gave birth to a cub named Bao Bao, which will celebrate her second birthday today with a frozen fruitsicle cake made of honey, apple juice, apple sauce, bamboo, carrots and beet juice.