Washington's National Zoo announced on Friday the surviving giant panda cub born during the last weekend is a male cub.
The zoo also said in its latest update posted online on Friday that after DNA tests, it also found Tian Tian, a male giant panda from the zoo, is the father.
The zoo's female giant panda Mei Xiang was artificially inseminated twice on April 26 and 27 with semen collected from Tian Tian and from a male panda in Wolong, China.
According to the zoo, the cub was doing well and weighed 167 grams as of Friday morning, gaining 27.9 grams in the past 72 hours.
Mei Xiang delivered twin cubs on Saturday, but the smaller one died Wednesday afternoon after experiencing continuous loss of weight and difficulty in breathing.
After initial autopsy, zoo officials said the cub had inhaled some food product which led to pneumonia. The dead cub was also a boy, said the zoo.
It was not the first time for the zoo and the public to receive bad news about death of a panda cub. In 2012, Mei Xiang gave birth to a cub that died six days later, and in 2013, she gave birth to a stillborn cub.
If the cub makes it through, it would be Mei Xiang's third surviving panda cub. Mei Xiang gave birth to her first cub Tai Shan on July 9, 2005 and then her second cub Bao Bao on Aug. 23, 2013.
