As kids around the area geared up for the first day of school today, the three-week-old Sumatran tiger cubs at the Smithsonian's National Zoo received their first veterinary exam—and they passed with roaring colors. Veterinarians determined that the two cubs are a male and a female. The male cub weighs a little more than 8 lbs. and the female weighs 7.5 lbs. During the exam the cubs received transponder microchips, and veterinarians collected blood and fecal samples from them. Veterinarians and keepers report the cubs are healthy, plump and growing quickly.

The Zoo's tiger, Damai, gave birth to the cubs Aug. 5 and has been caring for them since. The cubs will not be on exhibit for several months until they have completed a series of four additional health exams, during which they will receive all necessary vaccinations.

This is the first litter of Sumatran tiger cubs born at the Zoo since 2006, and the first litter for Damai. The cubs were sired by the Zoo's male tiger, Kavi. Sumatran tigers are listed as critically endangered by the International Union for Conservation of Nature. It is estimated that between 400 and 500 exist in the wild.

The Zoo will provide updates on the cubs on Facebook and Twitter.

Download set