|
CHINA> Photo
![]() |
|
This little piggy is a female
(China Daily/Asianewsphoto)
Updated: 2009-06-26 09:37 NANNING: Chinese scientists have claimed a commercial breakthrough after breeding 10 piglets whose sex was successfully selected before conception, heralding potential higher profits for farmers.
The healthy piglets were born last week on an experimental farm belonging to the Animal Science Institute in south China's Guangxi Zhuang autonomous region, the institute's top zoologist Lu Kehuan said yesterday. "They were the first pigs in China bred from sperm sorted into male and female chromosomes," he said.
Lu and his team separated sperm with the female X chromosome from sperm with the male Y chromosome, and used artificial insemination to inject the separated sperm into four sows. "Two of them gave birth after 115 days and the other two are due to give birth soon." Lu said the "custom-tailored" piglets were no different from other newborn pigs in terms of weight and appetite. But the technique is expected to help farmers manipulate birth rates and improve the quality of animal species, he said. Under normal circumstances, the average gender proportion of male and female piglets is 50:50. "On many pig farms in south China, a young boar is worth about 5,000 yuan ($715) more than a sow. An all-male brood of six therefore brings in an additional 15,000 yuan compared with an ordinary three male, three female brood," said Lu. Lu and his colleagues reported their first success in buffalo sex selection in 2006, when two female calves were born with X-bearing sperm. The technology is widely used today on milch cows in north China's Inner Mongolia autonomous region, whose vast pastures nurture quality cows and milk. Swine sperm, however, is more fragile and harder to maintain compared to buffalo's, Lu said. His team had carried out several sex selection tests on pigs before, all of which failed either to impregnate the sows or get the desired gender in piglets. "Theoretically, the same technique works on all mammals, including human beings," said Zeng Youquan, a member of Lu's project team. "But for legal and ethical reasons, we haven't considered applying it on humans. Nor will we in the near future." Choosing the sex of children is illegal in China, where people traditionally prefer boys over girls but most couples are allowed to have only one child. Hospitals are also banned from revealing the gender of a fetus to expectant mothers, fearing they might abort a female fetus. Fetus sex selection, however, is applied occasionally to prevent serious hereditary diseases, such as hemophilia and thalassemia, which are more likely in boys than girls, said Zeng. Xinhua |
||||||
主站蜘蛛池模板: 亚洲丰满熟女一区二区v| 西西人体www大胆高清| Se01短视频国产精品| 国产蜜臀视频一区二区三区| 国产精品理论片| 色偷偷人人澡人人爽人人模| 亚洲精品日韩久久精品| 一级二级三一片内射视频在线| 国产三级国产精品久久成人| 色噜噜狠狠色综合成人网| 蜜桃久久精品成人无码av| 国产在线不卡精品网站| 亚洲中文在线视频| 亚洲岛国成人免费av| 91嫩草尤物在线观看| 免费无码va一区二区三区| 97se亚洲综合在线天天| 免费播放岛国影片av| 影音先锋啪啪av资源网站| 中文字幕精品亚洲四区| 一区二区三区在线色视频| 成人午夜精品无码一区二区三区| 99国产精品国产精品久久| 东京热一精品无码av| 国产日韩一区二区天美麻豆| 一级欧美牲交大片免费观看| 日本韩国的免费观看视频| 尹人香蕉久久99天天拍| 国产精品熟女一区二区不卡| 欧美巨大极度另类| 91密桃精品国产91久久| 熟女无套高潮内谢吼叫免费| 体态丰腴的微胖熟女的特征| 麻豆果冻国产剧情av在线播放| 国产黄色大片一区精品| 国产精品最新免费视频| 国产亚洲精品成人aa片新蒲金| 人妻少妇久久久久久97人妻| 日韩人妻少妇一区二区三区| 亚洲国产精品无码一区二区三区| 亚洲AV日韩精品久久久久|