In vitro fertilized puppies born in the US

The seven puppies were born on July 10. Two of the puppies are from a Beagle mother and a Cocker Spaniel father, and the remaining five are from two Beagle pairs.

"Since the mid-1970s, people have been trying to do this in a dog and have been unsuccessful," said Alex Travis, associate professor of reproductive biology in the Baker Institute for Animal Health at Cornell University's College of Veterinary Medicine.

The findings were published in the PLOS ONE journal on Wednesday. "PLOS" stands for "Public Library of Science."

Travis said there were major ramifications for wildlife conservation. "We can freeze and bank sperm, and use it for artificial insemination. We can also freeze oocytes, but in the absence of in vitro fertilization, we couldn't use them," Travis said. "Now we can use this technique to conserve the genetics of endangered species."

"With a combination of gene editing techniques and IVF, we can potentially prevent genetic disease before it starts," Travis said. Dogs share more than 350 similar heritable disorders and traits with humans, almost twice as many as any other species.

The technique was developed in Britain in the 1970s and the first "test tube" baby was born there in 1978. Eggs are fertilized with sperm outside the body before the embryos are implanted into a female.

It has taken years for scientists to develop the technique for dogs, partly because their reproductive cycles differ from those of other animals.

jm/msh (Reuters, AFP)