The UK’s only female panda has been artificially inseminated in the latest attempt to produce a cub.
Tian Tian underwent the procedure at Edinburgh Zoo during her annual health check.
Keepers said it is too early to know if she is pregnant.
The zoo said in a statement on its website: “Tian Tian had her annual health check this morning and was artificially inseminated under expert veterinary care.
“We are pleased to say that all went well, though it is too early to know if she is pregnant at this very early stage.
“Tian Tian gave birth once before in 2007 and it really would be incredible for her to experience being a mother again. We will all be keeping our fingers crossed.”
Inseminating Tian Tian is said to be a “critical part of the giant panda international breeding programme”.
There are fewer than 2,000 giant pandas left in the wild and keepers hope her offspring could join them.
Tian Tian previously had cubs in China but not in the UK, where she and male companion Yang Guang arrived in 2011 as part of a 10-year contract with the Chinese government.
A natural breeding attempt was made in in 2012, with artificial insemination used instead each year between 2013 and 2017.
She was believed to be pregnant in August 2017, but her hormone levels and behaviour later returned to normal.
She was artificially inseminated again in 2019.
The statement from the zoo said attempts are not being made to breed with Yang Guang as he had both testicles removed in 2018 after tumours were found, although this was said not to be a factor in previous failed breeding attempts.
The male panda chosen this time is Hualong from the China Conservation and Research Centre for the Giant Panda, said to be a “good genetic match” for Tian Tian.
Breeding giant pandas is not an exact science and the zoo said keepers will only know for certain that Tian Tian is pregnant if she gives birth later this year.
The zoo’s statement added: “There is no definitive panda pregnancy test and giant pandas can delay implantation of fertilised eggs as well as having pseudopregnancies which mimic real pregnancies, all of which makes it very difficult to predict if and when they may give birth.”
Most giant pandas give birth in August or September but keepers cannot be “sure of an exact timeline”.
Earlier this year The Royal Zoological Society of Scotland, which runs Edinburgh Zoo, said the zoo’s giant pandas may have to return to China next year at the end of their contract due to financial pressures caused by coronavirus closures.
In the statement on Saturday, the zoo said any extension, if Tian Tian becomes pregnant, will have to be discussed with their Chinese colleagues, but she “at the very least would need to stay to raise any cubs until they were old enough to travel”.
Regarding the contract in general, the statement added: “It is too soon to say what may happen when the contract ends at the end of the year.
“We are in discussions with our colleagues in China and will update everyone as soon as possible.”