Fingers are crossed that the UK’s giant panda couple Tian Tian and Yang Guang will mate within days.
Edinburgh Zoo said female Tian Tian is about 10 days away from her short fertile window, perhaps less. The pair were introduced to each other before last year’s breeding season but did not mate.
The Royal Zoological Society of Scotland (RZSS) revealed that Tian Tian will shortly be in heat after tests showed the necessary hormonal crossover in progesterone and oestrogen had occurred.
Iain Valentine, director of giant pandas, said: “We are now able to predict that the important 36-hour breeding window when both pandas are likely to meet is imminent.
“Scientific results alone would suggest the day is just less than 10 days away; however, as Tian Tian’s behavioural changes are coming in so strongly, we cannot rule out that the key 36-hour window may be much sooner.
“Every individual giant panda is different and this is only the second time Tian Tian has come into season in Scotland, so it is difficult to make a precise prediction at this stage.
“The next steps are to continue behavioural observational and hormone testing to confirm when the annual window has arrived.”
Tian Tian and Yang Guang are the first giant pandas to live in the UK for 17 years.
Edinburgh Zoo, where the pair have lived since their arrival from China in December 2011, has employed a number of measures to synchronise the breeding cycles of the pandas, including controlled lighting, urine testing for hormone levels and enclosure swapping.
Mr Valentine said: “When the 36-hour window is here, Tian Tian and Yang Guang will meet several times to have the opportunity to mate and then, as Tian Tian finally ovulates and her hormones fall off, artificial insemination will also take place.”
If Tian Tian does fall pregnant, it will be July or the first half of August when Edinburgh Zoo experts will be able to confirm it by using ultrasound scans.
The majority of giant panda cubs are born at the very end of August or beginning of September.