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5/29/18 ~ Bei Moving Up To His Hammock

Moderator: Panda TA's
~~~~~~~~~~~~~~ ^ click 2X biggestThe panda team has started seeing more pronounced behavioral changes in Mei Xiang, which is normal and expected for a pregnant or pseudopregnant giant panda. Overall, she is spending more time sleeping and is less responsive to the keepers.
Mei Xiang is usually anxiously waiting at the door to venture outside for her bamboo breakfast when the keepers arrive in the morning, but lately she has been sleeping in, only rousing after the keepers have filled her yard with bamboo. That bamboo breakfast is increasingly becoming the only part of the day she chooses to spend outside. She is also eating less bamboo, which is normal for a panda in the final stages of a pregnancy or pseudopregnancy. However, she is still eating some of her favorite things like apples, pears and biscuits. She is also steadily building a nest in her den and the soft cushion of shredded bamboo now mostly covers the floor.
At some point in the next several weeks, Mei Xiang will likely choose to stay inside all day and spend almost all of her time sleeping. She also may start spending extended periods of time in her den. In the past she has moved some of her toys and feeders in the den to cradle like she would a newborn cub. She also will become much more sensitive to noise.
The changes in her behavior correlate with the hormonal changes endocrinologists at the Smithsonian Conservation Biology Institute have been tracking. Her urinary levels of progesterone are rising, which indicates that she is in her secondary hormone rise. This secondary rise indicates that Mei Xiang will either give birth or experience the final stages of a pseudopregnancy within the next month. Scientists cannot determine if a giant panda is pregnant from behavior and hormonal analysis alone because her behavior and hormones will mimic a pregnancy even if she is not pregnant.
The only definitive way to determine if Mei Xiang is pregnant before she gives birth is to detect a fetus on an ultrasound. Veterinarians have are conducting ultrasounds twice a week to track changes in Mei Xiang’s reproductive tract, but they have not seen anything yet. It is important that Mei Xiang is comfortable with the procedure and is trained to participate in it because she is more reactive to change and unfamiliar things at the end of a pregnancy or pseudopregnancy. If she is trained to participate in and is comfortable with having an ultrasound, it increases the chances she will participate in the final stages of a pregnancy or pseudopregnancy. However, she always has the choice to participate. If she chooses not to participate, she can leave the training chute at any time and veterinarians will not perform an ultrasound.
Giant pandas experience delayed implantation, meaning that an embryo floats in the uterus after fertilization and does not implant in the uterine wall until a few weeks before birth. It grows exponentially after it implants, but scientists do not understand what causes an embryo to finally implant in the uterine wall.
In the next several weeks, as we near the time when Mei Xiang will either give birth or the end of a pseudopregnancy, the panda cams will focus on her instead of rotating between her, Tian Tian and Bei Bei. Specially trained behavior watchers with Friends of the National Zoo will monitor her behavior 24 hours-a-day and look for signs of an impending birth.
Beginning today, June 24, the panda house will be closed to keep a quiet area around female giant panda Mei Xiang’s den. Although keepers are not able to confirm if she is pregnant, Mei Xiang is exhibiting expected, normal behaviors after the secondary hormone rise that are in line with both a pregnancy and pseudo, or false, pregnancy. She is building a nest in her den, has a decreased appetite, is sleeping more and is reacting to loud noises. Paws-crossed!
Pandas, like several other species, can undergo pseudopregnancies, where they do everything they would if they were pregnant. At the end of a pseudopregnancy, however, hormone levels return to baseline and females’ energy levels and behavior return to normal. Check out our FAQ on giant panda breeding and estrus here. We’ll continue to share updates via social media but also encourage you to sign up for the Giant Panda Bulletin. And then, there’s always the Panda Cam!
The closure will not affect the outdoor habitats and viewing areas. Please note that although Bei Bei and Tian Tian will have access to be outside until 2 p.m., due to the weather, the best time to see them will be outside from 8 a.m. to 10 a.m. Indoor viewing will be closed.
~~~~~~~~~~~~~~~~~~~A team of reproductive scientists, veterinarians and animal keepers at the Smithsonian’s National Zoo and Conservation Biology Institute have determined that giant panda Mei Xiang (may-SHONG) will not give birth this year. She was experiencing a pseudopregnancy during the past several months.
Endocrinologists had been tracking Mei Xiang’s hormones since she was artificially inseminated March 1. Her levels of urinary progesterone began to rise in early May, indicating that she would give birth to a cub, or experience the final stages of a pregnancy in 40 to 50 days. Her hormones returned to normal or “baseline” levels July 1, but she did not give birth indicating that she likely has been experiencing a pseudopregnancy. A final ultrasound today, July 5 confirmed that there is no developing fetus.
The panda team had also been tracking Mei Xiang’s behavior closely during the past several weeks. Specially-trained volunteers with Friends of the National Zoo started monitoring her 24-hours-a-day via the panda cams July 1, watching for specific behaviors associated with pregnancy and pseudopregnancy. Giant pandas’ behavior and hormones mimic a pregnancy even if they are experiencing a pseudopregnancy. Veterinarians conducted ultrasounds to track changes in Mei Xiang’s uterus and to try to detect a developing fetus.
Giant panda pregnancies and pseudopregnancies can last between three and six months. Mei Xiang’s denning behaviors will decrease, and staff expect her to return to her normal routine within a couple of weeks. The panda house will reopen today, July 5 and return to normal operating hours of 9 a.m. to 6 p.m. Visitors are also able to see the pandas on the panda cams, which are live on the Zoo’s website 24-hours-a-day, 7-days-a-week.
Mei Xiang has given birth to three surviving panda cubs with Tian Tian, all of which were born at the National Zoo. Her first cub, Tai Shan (tie-SHON), was born July 9, 2005 and now lives in China. Her second cub, Bao Bao (BOW-BOW), was born Aug. 23, 2013. Bao Bao moved to the Dujiangyan Panda Base in February 2017. On Aug. 22, 2015, Mei Xiang gave birth to her third cub, Bei Bei (BAY-BAY), who will move to China by the time he turns 4 years old. All panda cubs born at the Zoo return to China by the time they turn 4.
The Zoo received approval for its breeding plans from the China Wildlife and Conservation Association and the U.S. Fish and Wildlife Service, which monitors giant panda research programs in the United States.
Giant pandas are listed as “vulnerable” in the wild by the International Union for Conservation of Nature. There are an estimated 1,800 in the wild. Scientists and animal care specialists at the Smithsonian’s National Zoo and Conservation Biology Institute work with scientists in China studying giant panda reproduction and cub health, habitat and disease.
The Zoo will continue to provide updates on the pandas on Facebook, Instagram and Twitter using #PandaStory, and the Giant Panda e-newsletter.