Two rare Persian onagers (pronounced ON-uh-ger) became the first ever wild equids—members of the horse family—to be born using artificial insemination.
The onagers arrived on June 28 and July 9 at The Wilds, a 10,000-acre wildlife conservation center in Cumberland, Ohio. The births are the results of a collaborative four-year study with Smithsonian researchers at the Smithsonian Conservation Biology Institute (SCBI) in Front Royal, Virginia. The birth of these animals—previously little known in most parts of the world—opens a new door for future conservation efforts.
Not only is the onager one of the largest species of Asiatic wild ass, it's also one of the fastest; adults have been known to reach speeds of over 40 miles per hour. But despite its ability to outrun potential threats, this equid is now classed as an endangered species. Onagers were once abundant throughout China, Mongolia, and the Middle East, but it is estimated that only 600-700 now remain in just two protected areas of Iran. The desert habitat in which the onagers thrive is disappearing rapidly due to human settlement and overgrazing. And because onager meat can be sold easily, poaching is also a threat.
Fewer than 30 onagers live in zoos throughout the United States, and fewer than 100 live in zoos worldwide. The Smithsonian's SCBI has five.
The SCBI team—led by Mandi Vick, associate curator of research at Cleveland Metroparks Zoo—began studying the onager in partnership with The Wilds a little over three years ago. As a postdoctoral fellow, Vick helped develop methods for equid sperm collection and "cryopreservation" (freezing sperm). As it turned out, these methods came in handy for one of the inseminations of the onagers, which relied on previously frozen sperm to successfully impregnate a female.
The two foals were born from two of three onagers that the SCBI team had attempted to inseminate (the third failed to conceive). Further study is required to determine what may have prevented the third onager from conceiving; but researcher Budhan Pukazhenthi points to the potential stress incurred during the insemination process as a possible culprit. Pukazhenthi—a reproduction physiologist at SCBI—is largely optimistic. "It goes to reinforce that if you’re doing some basic research or studies on a species, you do have a fairly decent shot at being able to go that extra step and produce offspring," he says.
Why is offspring collection important?
"When you look at it in terms of long-term preservation of these species, we want every tool possible to have on-hand so we can keep the species healthy," says Pukazhenthi. "To now be shown that works, in a situation where an animal extremely relevant to the population fails to reproduce naturally, then we feel confident that we could use artificial insemination to get those numbers back in the population."