VOA常速英语:Test Tube Pups May Help Rescue Endangered Species

Scientists at Cornell University have proudly presented the first litter of dogs successfully born through in vitro fertilization, or IVF. The breakthrough may help in combating inherited diseases that affect canines as well as humans.
 
The litter of seven, born July 10, came from 19 embryos implanted in the same female dog. Five are beagles and two are beagle-cocker spaniel mixes.
 
Other animals, as well as humans, have been successfully bred through artificial insemination, but perfecting the process in dogs took decades because of the critical timing in fertilization of the female dog's eggs.

 
Previously, only one dog was born from a frozen embryo, in 2012, at the same Cornell University lab.
 
Scientists say the new success opens the door to saving endangered species of dogs.
 
“Like the African painted dog," said Dr. Alexander Travis of Cornell. "If we want to breed them in captivity and we collect, say, their eggs and sperm, we have to be able to do IVF to create new members of that species.”
 
Successfully fertilizing eggs in the lab could also help eliminate many of the disease traits in dogs.
 
“It opens up the possibility that we could identify certain genes that cause disease and then fix those, replace them with a good copy of the gene, before those dogs are even born," Travis said. "So instead of trying to cure disease, we can help prevent it from happening in the first place.”
 
Cornell scientists say that the complete understanding of in vitro fertilization of dogs will also help unveil the genetic basis of some of the more than 350 disorders that humans share with dogs.