Giant Panda Mei Xiang (may-SHONG) gave birth to twins at the Smithsonian’s National Zoo on August 22. The panda team witnessed the first cub’s birth at 5:35 pm. A second cub was born at 10:07pm.
A panda team of three keepers retrieved one of the cubs per the Zoo’s Giant Panda Twin Hand-Rearing protocol. The cub was placed in an incubator and was cared for by veterinarians and panda keepers. At this time, it has not been confirmed if the retrieved cub was the first born or second born. The retrieved cub was vocalizing very well and appeared healthy. It weighed 138 grams.
Giant Pandas give birth to twins approximately 50 percent of the time. This is only the third time a Giant Panda living in the United States has given birth to twins.
The panda team will alternately swap the cubs, allowing one to nurse and spend time with Mei Xiang, while the other is being bottle fed and kept warm in an incubator. The sex of the cubs won’t be determined until a later date.
As of this morning (August 24), the zoo reports that the panda cubs are doing well, but the panda team had a challenging night. When they tried to swap the cubs at 11p.m., Mei Xiang would not set down the cub she had in her possession. Consequently, the panda team cared for the smaller cub throughout the night until 7:05 am, when they successfully swapped the cubs. The panda team supplemented the smaller cub with formula by bottle-feeding. They were concerned that the smaller cub was not getting enough volume, so they moved to tube feeding which went well and quickly. Their goal is for each cub to spend an equal amount of time with their mother. Keepers stated, the newborn cubs are vulnerable and this first week is incredibly important and the risk remains high. The panda team is doing great work, around the clock, and will continue to keep the public posted.
Veterinarians first detected evidence of a fetus, on an ultrasound, August 19. It was the first time they had ever seen a fetus on an ultrasound, as Mei Xiang usually chooses not to participate in ultrasounds in the final weeks of her pregnancies and pseudo-pregnancies. At the time, the fetus detected was about 4 centimeters in length.
Reproductive scientists from the Smithsonian’s National Zoo and Conservation Biology Institute (SCBI) artificially inseminated Mei Xiang April 26 and 27. For the first time, scientists used semen collected from a Giant Panda named Hui Hui (h-WEI h-WEI). He lives at the China Conservation and Research Center for the Giant Panda in Wolong and was determined to be one of the best genetic matches for Mei Xiang. A cub by Mei Xiang and Hui Hui would be very genetically valuable, helping to preserve the genetic diversity of the panda population in human care.
The sample from Hui Hui was frozen and flown from China to the cryopreservation bank at the National Zoo. Scientists also used high-quality fresh semen collected from the Zoo’s male Giant Panda, Tian Tian (t-YEN t-YEN), for the artificial inseminations. DNA analysis will determine the sire of the cub.
SCBI scientists confirmed that a secondary rise in Giant Panda Mei Xiang's urinary progesterone levels began July 20. This signaled that Mei Xiang would either have a cub or experience the end of a pseudo-pregnancy, within 30 to 50 days.
At that time, Mei Xiang also began exhibiting behaviors consistent with pregnancy or pseudo-pregnancy. She started nest building, spending more time in her den, sleeping more and eating less. In recent weeks, she also spent time body licking and cradling toys. The area of the David M. Rubenstein Family Giant Panda Habitat, closest to her, den was closed to provide her with quiet, since Mei Xiang shows extra sensitivity to noise during the final weeks of a pseudo-pregnancy or pregnancy. Keepers moved to round-the-clock behavior watch via panda cam to monitor Mei Xiang Aug. 20.
The panda team expects Mei Xiang to spend almost all of her time in her den for the next two weeks with her offspring. The David M. Rubenstein Family Giant Panda Habitat has been closed to the public since August 20, and will remain closed until further notice to provide quiet for Mei and her cubs. They will continue to be visible on the panda cams. Visitors can also see Tian Tian and two-year-old Bao Bao (BOW-BOW), in their outdoor habitat and on the panda cam.
Mei Xiang has given birth to two surviving cubs: Tai Shan (tie-SHON) and Bao Bao. Tai Shan was born July 9, 2005, and he now lives in China. Bao Bao was born August 23, 2013. She will live at the Zoo until she turns 4; at that time, Bao Bao will also go to live in China and, eventually enter the Giant Panda breeding program. Both Tai Shan and Bao Bao were born as the result of artificial inseminations.
The Zoo will continue to provide daily updates on Mei Xiang and the cubs through social media. Follow #PandaStory on Instagram (@SmithsonianZoo) and Twitter (@NationalZoo) for the latest. If the panda cam is maxed out due to high-demand, download the Zoo's app (App Store or Google Play) to get access to all animal cams.