San Diego Zoo Clones Endangered Horse
2020-10-21
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1At the San Diego Zoo, in Southern California, little Kurt looks and acts like any other baby horse.
2He likes to play, pushes against anything that gets in his way, and runs to his mother for milk when he is hungry.
3But the 2-month-old differs from every other baby horse in the world in a major way: Kurt is a clone.
4He was created in a laboratory.
5Scientists used cells taken from a male Przewalski's horse in 1980.
6The cells had been frozen for the last forty years.
7The scientists also took an egg from a female horse of a different breed.
8Then, they removed the egg's nucleus and replaced it with the cells from the Przewalski's horse.
9The resulting embryo was placed in the womb of another female horse for development.
10She gave birth to Kurt on August 6.
11Scientists have cloned more than twenty other kinds of animals, including dogs, cats, pigs, cows and mice.
12In 2018, researchers in China created monkeys for the first time using the same cloning methods that produced the first cloned animal, Dolly the sheep, in 1996.
13San Diego Zoo officials say Kurt is the first cloned Przewalski's horse, a rare and endangered breed.
14The zoo sees Kurt's birth as a major step in efforts to reestablish the population of the Przewalski's horse, also known as the Asiatic Wild Horse or Mongolian Wild Horse.
15The small, thickset horses are believed to have disappeared from the wild.
16About 2,000 live in zoos and wildlife centers.
17Bob Wiese is chief life sciences officer at San Diego Zoo Global, which operates the zoo.
18He said that Kurt is expected to be one of the most genetically important individuals of his breed.
19"We are hopeful that he will bring back genetic variation important for the future of the Przewalski's horse population," he added.
20Kurt was named for Dr. Kurt Benirschke, who created the Frozen Zoo, a research and collection center at the San Diego Zoo.
21It provided the scientists with the Przewalski's horse cells used to make Kurt.
22The zoo worked jointly with the California conservation group Revive & Restore and the Texas-based company ViaGen Equine in creating Kurt.
23He was born at a veterinary facility in Texas.
24He is expected to continue to live there with his mother for another year.
25Later, Kurt will move to the San Diego Zoo to live with other Przewalski's horses.
26Zoo officials hope Kurt will someday become a father himself.
27Przewalski's horses take their official name from Russian explorer Nikolai Przewalski, who found a skull and skin of one and shared it with a Russian museum.
28At one time the horses lived throughout Europe and Asia, says the Smithsonian's National Zoo and Biology Conservation Institute.
29Growing populations of humans and farm animals pushed them out of Europe and east into Asia.
30Outside of zoos, they exist today only in special protected areas of Mongolia, China, and Kazakhstan.
31The Smithsonian says Przewalski's horses are the only true wild horses left in the world.
32It says that wild horse groups in North America and Australia are not truly wild because their ancestors were horses that escaped human owners.
33I'm Jonathan Evans.
1At the San Diego Zoo, in Southern California, little Kurt looks and acts like any other baby horse. He likes to play, pushes against anything that gets in his way, and runs to his mother for milk when he is hungry. 2But the 2-month-old differs from every other baby horse in the world in a major way: Kurt is a clone. He was created in a laboratory. 3Scientists used cells taken from a male Przewalski's horse in 1980. The cells had been frozen for the last forty years. The scientists also took an egg from a female horse of a different breed. Then, they removed the egg's nucleus and replaced it with the cells from the Przewalski's horse. 4The resulting embryo was placed in the womb of another female horse for development. She gave birth to Kurt on August 6. 5Scientists have cloned more than twenty other kinds of animals, including dogs, cats, pigs, cows and mice. In 2018, researchers in China created monkeys for the first time using the same cloning methods that produced the first cloned animal, Dolly the sheep, in 1996. 6San Diego Zoo officials say Kurt is the first cloned Przewalski's horse, a rare and endangered breed. 7The zoo sees Kurt's birth as a major step in efforts to reestablish the population of the Przewalski's horse, also known as the Asiatic Wild Horse or Mongolian Wild Horse. The small, thickset horses are believed to have disappeared from the wild. About 2,000 live in zoos and wildlife centers. 8Bob Wiese is chief life sciences officer at San Diego Zoo Global, which operates the zoo. He said that Kurt is expected to be one of the most genetically important individuals of his breed. 9"We are hopeful that he will bring back genetic variation important for the future of the Przewalski's horse population," he added. 10Kurt was named for Dr. Kurt Benirschke, who created the Frozen Zoo, a research and collection center at the San Diego Zoo. It provided the scientists with the Przewalski's horse cells used to make Kurt. 11The zoo worked jointly with the California conservation group Revive & Restore and the Texas-based company ViaGen Equine in creating Kurt. He was born at a veterinary facility in Texas. He is expected to continue to live there with his mother for another year. 12Later, Kurt will move to the San Diego Zoo to live with other Przewalski's horses. Zoo officials hope Kurt will someday become a father himself. 13Przewalski's horses take their official name from Russian explorer Nikolai Przewalski, who found a skull and skin of one and shared it with a Russian museum. 14At one time the horses lived throughout Europe and Asia, says the Smithsonian's National Zoo and Biology Conservation Institute. Growing populations of humans and farm animals pushed them out of Europe and east into Asia. Outside of zoos, they exist today only in special protected areas of Mongolia, China, and Kazakhstan. 15The Smithsonian says Przewalski's horses are the only true wild horses left in the world. It says that wild horse groups in North America and Australia are not truly wild because their ancestors were horses that escaped human owners. 16I'm Jonathan Evans. 17The Associated Press reported this story. Caty Weaver adapted it for VOA Learning English. Hai Do was the editor. 18________________________________________________________________ 19Words in This Story 20breed - n. a group of animals or plants thought to be related to one or more common ancestors 21variation - n. the act or process of being different