Test-tube puppies are the first born via in vitro fertilization

While doctors have successfully been using in vitro fertilization for years as a reproductive treatment, the same procedure hasn’t been available for our canine friends—until now.

According to a new paper published in the journal PLOS ONE, scientists have successfully been able to produce living, healthy puppies through in vitro fertilization.

“Since the mid-1970s, people have been trying to do (IVF) in a dog and have been unsuccessful,” study author Alex Travis, associate professor of reproductive biology at Cornell University, said in a statement.

Establishing an IVF method for dogs has been difficult due to their distinctive and challenging reproductive physiologies. Domesticated dogs ovulate just about once or twice a year, and unlike many other mammals, dogs release less-than-mature eggs during ovulation rather than the mature eggs necessary for effective IVF.

In the new study, the team learned that if they left the egg in the oviduct one more day, the eggs reached the point where fertilization was probably ready to happen.

In addition, the female canine system plays a role in helping sperm fertilize an ovum, so scientists had to replicate those conditions in the lab. Based partly on Travis’s prior work on sperm physiology, the team discovered that sperm might be artificially helped by adding magnesium to the cell culture.

Success in fertilization rates up to 90 percent

“We made those two changes, and now we achieve success in fertilization rates at 80 to 90 percent,” Travis said.

Because female dogs can only conceive once or twice a year, embryos must be produced in advance and conserved until the host female is at the correct point in her cycle. The team resolved this by using a method developed by Travis’s lab, which resulted in Klondike, the first puppy born from a frozen embryo in the Western Hemisphere.

In addition to affecting the pet industry, the study also has implications for the conservation of endangered canine species like dhole and the maned wolf.

“We can freeze and bank sperm, and use it for artificial insemination,” Travis said. “We can also freeze oocytes, but in the absence of in vitro fertilization, we couldn’t use them. Now we can use this technique to conserve the genetics of endangered species.”

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Feature Image: Mike Carroll