LONDON (AFP) - Britain's only female giant panda, Tian Tian, has been artificially inseminated after failing to mate with her male partner Yang Guang, Edinburgh Zoo said on Tuesday.
Experts had been hopeful the pair, donated by China in 2011, would mate this breeding season but Tian Tian's hormone levels plummeted before they had the chance.
"Time restrictions meant we needed to move quickly to artificial insemination," said Mr Iain Valentine, director of giant pandas for the Royal Zoological Society of Scotland.
The procedure took place on Sunday but it will not be clear whether Tian Tian is pregnant until she gives birth, which could be in August or September.
Both pandas recovered quickly from the insemination process, with Yang Guang enjoying honey and bamboo 15 minutes later, the zoo said.
Their enclosure will remain closed to the prying eyes of the public until Wednesday.
Tian Tian, whose name means Sweetie, was also artificially inseminated last year but the zoo suffered a huge disappointment when she had a late-term miscarriage.
Mr Valentine said that from the start, when the pandas started to show breeding behaviour early this spring, both were showing very positive signs.
"We were hopeful natural mating would occur this year, but in the end Tian Tian's hormones started to fall quickly, which meant her breeding window could be much shorter."
A Chinese expert was "confident" the pair would mate naturally but the zoo went ahead with artificial insemination using semen from Yang Guang, fearing that time would run out.
The zoo acquired Tian Tian and Yang Guang, whose name means Sunshine, from China in December 2011 but the pair have so far failed to mate.
Pandas, whose natural habitat lies in mountainous south-western China, have a notoriously low reproductive rate and are under pressure from factors such as habitat loss. China has about 1,600 pandas living in the wild. Their normal breeding season is mid-April to May.