First I.V.F. Puppies Are Born in Breakthrough at Cornell
By CHRISTINE HAUSER

Scientists at Cornell University announced Wednesday that for the first time they had been successful in delivering a litter of puppies conceived through in vitro fertilization.

In what was described as a “breakthrough,” the results of the research, which took decades to accomplish, were announced in the scientific journal Public Library of Science ONE and online by the university.

The successful multiple, live births open the door for the future conservation of endangered species and for the use of gene-editing technologies that could help scientists get rid of inherited diseases in dogs.

The research could also help in the study of genetic diseases, because dogs share more than 350 disease traits with humans, almost twice as many as any other species.

“Since the mid-1970s, people have been trying to do this in a dog and have been unsuccessful,” said Alexander J. Travis, associate professor of reproductive biology in the Baker Institute for Animal Health in Cornell’s College of Veterinary Medicine.

The scientists described two main challenges, such as finding the optimal stage for fertilization of the female dog’s eggs, and simulating the conditions in the lab for preparing the sperm. Ultimately, the team was able to achieve fertilization rates of 80 percent to 90 percent, Dr. Travis said.

Eventually, 19 embryos were transferred to a host female dog, which gave birth July 10 to seven puppies: five conceived from beagles and two that were a beagle and cocker spaniel mix.

Dr. Travis’s team reported in 2013 the successful birth of Klondike, a beagle-Labrador mix puppy born from a frozen embryo in a procedure that used artificial insemination.

But the announcement this week is different because it involves a litter and because the multiple embryos were cultivated in a dish and then implanted in the recipient female, Skylar Sylvester, one of the researchers, said in a telephone interview.

試管狗成功 瀕危物種有救

美國一個團隊以體外人工受精（IVF）技術讓一隻代理孕母狗生下全球第一批試管狗，這七隻試管狗的誕生不僅豎立重大科學里程碑，也可望成為拯救瀕臨絕種動物的關鍵。

美聯社報導，這個團隊由獸醫、科學家和實驗室研究人員組成，研究成果九日發表於公共科學圖書館期刊。康乃爾大學貝克動物健康研究所實驗室負責人崔維斯說：「我們每人抱起一隻小狗，用小毛巾撫揉，當牠們開始扭動並叫出聲音，我們知道成功了。牠們緊閉雙眼，很可愛。我們仔細檢查，確保牠們外形正常而且都在呼吸。」

研究報告第一作者珍妮佛．長島說，狗IVF技術將有許多用途，包括保護瀕絕動物、移除疾病基因等，相關研究並且具有應用於「人類疾病模型」的潛力。

這窩七月十日誕生的小狗是米格魯（比高小獵犬）、拉布拉多和西班牙長耳獵犬（可卡）的混種狗，至今都很健康，其中六隻被領養，最後一隻母狗由實驗室照顧。研究人員在七隻狗的指甲上塗上不同顏色的指甲油，以辨認並追蹤小狗成長。崔維斯領養了兩隻，並用指甲色彩命名，分別是紅色和綠色。小狗出生時每隻約四百五十克重。

IVF技術讓精卵在體外結合，受精卵最初幾天在試管中培育；IVF技術廣泛用於人類生育，首位試管嬰兒一九七八年誕生，但試管狗實驗直到七月才成功。

史密森保護生物研究所生殖生理學家柯米佐利說：「狗和人生理構造天差地遠。」狗懷孕期僅兩個月，母狗每年發情一到兩次，排出未成熟卵子，非IVF技術所需成熟卵子。

康乃爾大學前年透過人工受孕讓一隻米格魯懷孕，收集冷凍胚胎後移植到代理孕母狗體內，首度成功用冷凍胚胎培育出小狗康戴克。

原文參照：
http://www.nytimes.com/2015/12/11/science/cornell-announces-a-litter-of-puppies-born-using-ivf.html

Video：The first litter of puppies ever conceived by in vitro fertilization were born in July, and Cornell University's College of Veterinary Medicine, which pioneered the feat, released this footage on Thursday.
http://www.nytimes.com/video/us/100000004086478/first-test-tube-puppies-born.html

2015-12-11．聯合報．A13．國際．編譯陳韻涵