Giant panda Kai Kai keeps caretakers in Singapore on toes over possible pregnancy

Giant panda celebrities Kai Kai and Jia Jia celebrated their birthdays at Singapore's River Safari on Thursday, with all spotlight focusing on whether Jia Jia is pregnant or not.

Female panda Jia Jia turns seven on Thursday while its mate, Kai Kai will soon turn eight on Sept. 14. The two have crossed their first mating season in April this year, but the natural mating has been unsuccessful. Therefore, caretakers and specialists in River Safari have decided to conduct artificial insemination on Jia Jia.

In the past two months, Jia Jia has been eating less bamboo, sleeping more, spending more time in her den and her hormone levels are increasing -- all signs consistent with pregnancy or pseudopregnancy. However, it is still uncertain whether Jia Jia is pregnant, as giant pandas commonly display pseudopregnancies and experts worldwide are often not able to determine pandas' pregnancy status until a late stage.

Weekly ultrasound scans also failed to detect a foetus, but the results are still inconclusive.

Serena Oh, assistant director of Veterinary Services of Wildlife Reserves Singapore, said that even ultrasound can tell a lie.

"For giant pandas, it's actually quite difficult. It's not like other animals which you can actually clearly see the foetus. One thing I would say is that the foetus is quite small, and the other thing is that because you have all the other organs, it kind of cover the foetus, so sometimes it's hiding, that's why it's very hard to actually try the ultrasound to see the foetus."

The gestation period for a giant panda is typically five months, and the foetus only starts to develop a few weeks before birth.

But as the due date for Jia Jia to deliver a baby was the end of last month, Cheng Wen-Haur, chief life sciences officer of Wildlife Reserves Singapore, said that it is likely that Jia Jia is displaying pseudopregnancy. Cheng said that they will conduct another ultrasound scan at the end of next week, and by then, it would still be a "guessing game."

The pandas' birthdays will be marked with a Panda Party Week from Sept. 5 to 13, where both bears will receive daily treats as a form of enrichment. In addition, visitors can look forward to interactive booths to learn more about giant pandas, while children born in 2007 and 2008 can get free entrance to River Safari in September.

Kai Kai and Jia Jia, known as Wu Jie and Hu Bao respectively in China, arrived in the city state on Sept. 6, 2012. They will be staying in Singapore for 10 years. Endi