San Diego Zoo veterinarians gave the 24-year-old giant panda Bai Yun an ultrasound test Friday in hopes that the mother of six is pregnant again.
The 240-pound panda was lying still while being fed honey-water from a squeeze bottle during the examination, which lasted about 20 minutes.
There was no indication yet of a cub on the way.
Animal care staff will continue to monitor Bai Yun with regular ultrasounds, thermal imaging, and hormone testing over the next few weeks. Zoo staff members are keeping the area around Bai Yun’s den quiet, and only essential staff is being allowed in the area.
Following natural breeding sessions between Bai Yun and Gao Gao in March, which didn’t appear to animal care staff to be successful, it was decided, in collaboration with Chinese conservation partners, to conduct artificial insemination with sperm stored in the Frozen Zoo genetic bank. The sperm used was from giant panda Shi Shi, who was the first breeding partner for Bai Yun.
A panda’s fertilized egg remains suspended until a trigger in the environment indicates it is time to implant. The trigger is still unknown to scientists. Giant pandas routinely delay the implantation of the fetus as long as four months.
If a cub is born, Bai Yun will be the oldest giant panda known to give birth to a cub.
