Breeding of captive giant pandas in China has entered its peak this year.

　　Xinhua News Agency, Chengdu, April 6 (Reporter Yu Li, Feng Changyong) The reporter learned from the China Giant Panda Conservation and Research Center, which has the largest captive giant panda population in the world, that the center has completed nearly half of the breeding and breeding tasks of captive giant pandas this year, and the giant panda breeding has entered a peak period.

　　By the end of 2015, the number of captive giant pandas in the center had reached 218. Zhang Guiquan, director of Ya ‘an Base of China Giant Panda Conservation and Research Center, said that this year, 26 female pandas and 19 male pandas participated in the national captive giant panda breeding program. Since the first female panda was bred in late February, as of April 6, 10 female pandas have been bred. Among them, 6 were bred by natural mating, the other 2 were bred by natural mating with artificial insemination, and the remaining 2 were completely artificially inseminated.

　　"So far, this year’s breeding work has been completed well. The biggest feature is that the natural mating rate is relatively high, and the pregnancy rate of female pandas that have successfully mated naturally is over 90%, which is a good momentum for this year’s breeding work." Zhang Guiquan said.

　　"Under the current captive conditions, the number of male giant pandas with natural mating ability is very rare, accounting for less than 5% of the population. This year, the center belongs to the 7-year-old male giant panda ‘ An An ’ The first successful natural mating at Ya ‘an base on February 29th marks the addition of a male animal with natural mating ability to the captive giant panda population, which also shows that the quality of our captive giant panda population is constantly improving. " Zhang Guiquan said.

　　According to reports, at present, the artificial breeding of captive giant pandas in China is included in the unified planning, and the optimal pairing is carried out according to the principle of eugenics, so as to ensure the genetic diversity of the population to the greatest extent. There are 56 female pandas participating in the breeding program this year, and more than one third of them are from the China Research Center for the Protection of Giant Pandas.

　　There are three major problems in the development of captive giant panda population: difficulty in estrus, difficulty in mating and conception, and difficulty in survival of cubs. According to zhangxin, the breeder of the center, giant pandas are in estrus every spring. With the increase of temperature, their hormone level, estrus behavior and mating desire will decrease from May, which will affect the mating quality. Therefore, March and April are the prime time for giant pandas to breed. In order to ensure that female pandas are pregnant, some will also receive artificial insemination as appropriate after natural mating.

　　In recent years, the artificial breeding of giant pandas in the center has been carried out at Bifengxia base in Ya ‘an. The reporter saw at the base on the 6th that the staff was preparing to breed the 7-year-old female panda "Jojo". Because Jojo’s estrus behavior was not typical enough, she was not allowed to mate naturally. In this regard, Zhang Guiquan said that this is a normal situation.

　　It is reported that female giant pandas not only have a short estrus time, but also need to mate with each other to be successful. If there is no electricity between pandas, mating may fail even during estrus. In addition, even if natural mating is successful, it is very difficult for female giant pandas to finally give birth to panda babies — — Their eggs can only survive for 36 to 40 hours. Even with breeding, only 30% to 40% of female giant pandas can get pregnant successfully, while the survival rate of their cubs is less than 40%.