As Mexico's two resident giant pandas age, Mexico is looking to China to help breed a new generation of the famously difficult-to-reproduce creatures, at least in captivity.
In the past five years, specialists from both countries have been working on artificially inseminating the youngest of the two females, Xin Xin, with sperm brought over from China, since Shuan Shuan's more advanced age barred any attempts at insemination.
But even that is no longer an option, according to Juan Arturo Rivera Rebolledo, director of the Mexico City zoo where the pandas reside, who added that the final attempt at insemination, which was unsuccessful, was in 2014.
"For 2015, we have decided not to make any more attempts at artificial insemination, given Xin Xin's age and in order not to risk her state of health," Rivera said in an interview with Xinhua.
That is why, he said, Mexico is looking into the possibility of asking China to donate another giant panda to Mexico's Chapultepec Zoo, which in 1980 became the first institution outside China to successfully breed giant pandas in captivity.
"The Mexican government is very eager to establish fraternal ties of goodwill with the government of China, to once again have a pair of giant pandas and maintain the species' breeding program, which has been one of the most successful in the world over the past four decades," said Rivera.
There have been eight live births at the zoo, since China first donated the pair Pe Pe and Ying Ying to Mexico in 1975.
"Without any doubt, the Chapultepec Zoo is a model worldwide, due to the success it has had since 1975 in adapting the panda couple and later in breeding them, succeeding in preserving three generations of the species, which have captivated all Mexicans for years," added Rivera.
In 1980, Pe Pe and Ying Ying gave birth to the first panda born in captivity outside China. Unfortunately, Xen Li died after only eight days, crushed when her mother rolled over in her sleep.
Pandas are so small at birth that they weigh just over 100 grams, making them especially vulnerable to such incidents and lowering their chances of survival.
Mexico, however, proved to be fertile ground. The panda pair had a total of seven cubs, three male and four female, four of which reached adulthood and only one of which, Tohui, went on to reproduce via artificial insemination, giving birth to Xin Xin, now 25.
Shuan Shuan, 28, is considered one of the longest living pandas in both captivity and the wild and, according to Rivera, is "in very good physical condition and spirits."
"The fact that Shuan Shuan has lived to be 28 is a reflection of the maximum care" she has received at the zoo, Rivera said.
Still, while "both pandas maintain a very good quality of life, they are showing age-related symptoms," such as becoming less active and having more difficulty moving, said Rivera.
By working together, he indicated, China and Mexico could continue the success the Latin American country has had in breeding and preserving the endangered species.
