China's Calf-cloning Technology at Advanced Level

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Last updated at: (Beijing Time) Monday, December 24, 2001

China's Calf-cloning Technology at Advanced Level

An expert panel said Saturday that the technology developed in cloning China's first two skin cell-based calves equals that used by foreign countries or may even be more advanced.

According to the panel, three new technologies developed during cloning are thought to be unique and promising: a new cell nucleus-removing method causing less harm to the oocyte; a new system for breeding re-organized embryos of higher developmental rate for blastula; and successfully using cells frozen below minus 35 Celsius degrees as nucleus donors.

An expert panel said Saturday that the technology developed in cloning China's first two skin cell-based calves equals that used by foreign countries or may even be more advanced.

The panel was formed by eight animal experts, biologists and China's chief panda-cloning experts from the Zoological Society of China and the Institute of Zoology under the Chinese Academy of Sciences.

First two skin-cell cloned calves in good condition

DNA checks prove that the two calves are not genetically related to the cows that gave birth, but related to the cow providing the cells, the panel said.

The two calves were born about one and half months ago at the Laiyang Agricultural College in the eastern province of Shandong. They were both cloned by epidermal cells taken from the same beef cow fetus.

According to the panel, three new technologies developed during cloning are thought to be unique and promising:

a new cell nucleus-removing method causing less harm to the oocyte;

a new system for breeding re-organized embryos of higher developmental rate for blastula;

and successfully using cells frozen below minus 35 Celsius degrees as nucleus donors.

The two calves, Kangkang born on November 3 and Shuangshuang three days later, calves are female and black and have been doing well.

Kangkang weighs 71 kilograms and Shuangshuang 71.5 kilograms, according to sources.

First cloned calf died from accident

China's first cloned calf was born in mid-October in Shenzhen in south China's Guangdong Province, but died 80 minutes after birth.

China's First Two Skin-cell Cloned Calves in Good Condition

China's first two calves cloned from skin cells have been doing well since their birth just over a month ago at the Laiyang Agricultural College in Shandong province. Both are female and black. Kangkang, born on November 3, now weighs 53.5 kilograms, and Shuangshuang, born three days later, weighs 54.5 kilograms.

The calves' breathing and heart rate were normal, according to experts with the college.

China's First Cloned Cattle Died from Accident 80 Minutes After Birth

China's first cloned cattle was born smoothly in Shenzhen Lupeng Company Transgenic Animals Breeding Base on Saturday morning. It marks China's cloning propagation technology has taken its place in the front ranks of the world. However, the calf met unexpected disaster just after birth. Because of the carelessness of the breeder, it got milk choked in the trachea and ultimately died merely one hour and 20 minutes after birth. Full text

China Clones Scores of Plants, Pigs, Sheep, Rabbits, Cows

China has already developed 47 transgenic plant species, cloned goats and transplanted genes into pigs, rabbits, sheep and cows, according to an official report released on May 29, 2001. Full text

Chinese Government, Scientists Oppose Human Cloning

China opposes any experiments for the purpose of human cloning, but will allow "closely-monitored" embryo stem cell research for treatment and prevention of disease, the Ministry of Health announced on November 29, 2001. Full text

China's First Two Skin-cell Cloned Calves in Good Condition

Second Cloned Cow Was Born in Shandong

China's First Cloned Cattle Died from Accident 80 Minutes After Birth