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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.
Caesarian birth given after nine-month pregnancy
As sources say, the success of cloned calf results from a long time of hard efforts.
In June last year, a research group headed by Chen Yongfu, professor of China Agriculture University (CAU), went to New Zealand and started the selection work of embryo there. They took the somatic cell from cattle and made external culture. Then they selected proper ovum from female cattle in shambles. Under the microscope, which can magnify the objects two hundred times their actual size, scientists took out the DNA of the ovum so as to create a growing environment to the somatic cell. Then they put the somatic cell besides the ovum with only a vacant shell left. Stimulated with electricity, the two integrated as one. The somatic cell began to grow in the ovum. After culture in the lab, scientists got cloned embryo. Later, the research group froze the embryos with liquid nitrogen and delivered them back to China. On January 30 this year, the group came to Lupeng Base and transplanted 64 embryos. Four female cattle got pregnant. Before the birth of the calf, three mother cattle aborted unexpectedly. Lupeng Company and Professor Chen Yongfu made a prompt decision to give the remaining one a caesarian birth operation to avoid dystocia.
Healthy calf born in 15 Minutes
Together with Chen Yongfu and Zhang Yali, journalists gathered in the Transgenic Animal Breeding Base of Lupeng Company in Kuiyong on Early Saturday morning.
Obviously, everybody in the base was very excited. The mother cattle going to give birth to the calf was lying on the vacant land with four hoofs bound. Its hair on abdomen has been shaved. Heartbeat: 92 times per minute; temperature: 38.9 centigrade; breath: 36 times per minute. Everything was normal. The journalist recorded down the whole course of the birth of China's first cloned cattle.
8:45, sluicing and sterilizing; 8:50: local anaesthesia;
9:00, operation began. Professor Qi incised an over 20cm cut with scalpel in the abdomen of the mother cattle. Firstly came the skin, then the tendon, the muscle, the celiac wall and uterine wall that were opened one after another;
9:13, professor Qi said "got it". A hind hoof, white touched with yellow, firstly appeared to the journalist, then came the other hind hoof.
9:15, a small calf, black alternating with white, perfectly got out!
Weight: 39 kg, healthy". It declared the successful birth of China's first cloned cattle!
Accidental death after 80 minutes
The item cloned cattle was jointly carried out by Chen Yongfu's research group and Shenzhen Lupeng Company. Chen Yongfu, hiding in the meeting room, dared not turn up all the time, now could hardly conceal his delight and treat the journalist to a cigarette. Being the chief expert for the item of "Animal Mammary Gland Biologic Reactor", one of the items of the National 863 Program, Chen said to the journalists that the birth of the cloned cattle is a very important achievement of the key item of "Animal Mammary Gland Biologic Reactor" of the National 863 Program. It marks China's cloning technology has advanced to the front ranks of the world.
However, just when the journalists focused on the heroes one after another, an accident took place out of everyone's expectation. The little cloned calf had a difficulty in breathing! As a matter of fact, the breeder got the calf choked by milk when feeding it. The milk got into its trachea and the calf finally died in spite of all the effort for emergency rescue made.
10:35, the little cloned calf died merely 80 minutes after birth.
Scientists to foster second group of cloned cattle
Seeing the dead calf, Zhang Yali, with surgical uniform on, cried herself hoarse, "What you've done!" "How much efforts we've made to see this!" "To foster the embryo, our research workers slept on the floor for more than 40 days. After the embryos were transported back, we conducted embryo transplant in spite of the severe cold during the Spring Festival". "We held discussions late till 11 or 12 o'clock nearly every evening. Now we finally witnessed the successful birth. The whole course turned out to be so smooth. The calf was so healthy. This has proved that our cloning technology does work. However, it died from breeding accident��" all the persons at the spot were visibly moved.
Despite the accident, the birth of the cloned cattle proved that the technology is successful. Before this, CAU and Shenzhen Lupeng Company had succeeded in breeding transgenic sheep. Zhang Yali told the journalist that Lupeng Company would keep on cooperating with CAU in breeding a second group of cloned cattle. They plan to make the embryo in Australia and conduct the transplant around the Spring Festival next year.
By PD Online Staff Du Minghua
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