Antonio Calanni / AP The first clone produced from the gelded endurance champion Pieraz, cavorts in a field near Cremona, Italy, in 2005.

A federal judge in Texas on Monday ordered the American Quarter Horse Association to allow cloned horses and their offspring to be entered into the breed’s official registry, a decision that could soon clear the way for the genetically engineered animals to compete at scores of racetracks in the U.S. and elsewhere.

“We’re excited. It’s been a tough battle,” said rancher Jason Abraham of Canadian, Texas, one of two plaintiffs in the lawsuit alleging that the AQHA had violated federal antitrust law and the Texas Free Enterprise and Antitrust Act by refusing to register horses produced by cloning.

“We’ve asked for nothing special,” he said. “All we want to do is compete like everyone else, just enter the market.”

The AQHA, the official body of quarter horse racing, issued a statement late Monday indicating that it will ask the court to enter a “take-nothing judgment” in favor of the association “based upon the fact that the jury’s verdict was not supported by the evidence entered at trial.” If that motion is dismissed, it said it will appeal the verdict.

Nancy Stone, one of four attorneys representing the plaintiffs -- Abraham and Texas veterinarian Gregg Veneklasen -- said an appeal could delay the registering of cloned quarter horses for about a year if U.S. District Judge Mary Lou Robinson issued a stay of her order in the interim.

Cloning of animals is accomplished by transplanting the genetic information from a cell in a donor animal – either dead or alive -- into an unfertilized egg cell whose genetic information has been destroyed or physically removed. In the case of horses, that egg is then implanted into a surrogate mare, where — if everything goes smoothly — it develops into a viable foal.

The effort to force the AQHA to accept clones has been controversial. Proponents of cloning say it offers a way to return the DNA of champions who are either deceased or otherwise unable to reproduce to the genetic pool and could help reduce diseases prevalent in quarter horses by enabling breeders to “silence detrimental genes.”

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The AQHA, on the other hand, argued that cloning doesn't improve the breed and would render unusable its DNA-based system of tracking horses’ pedigrees.

Quarter horse racing, which generated more than $300 million in wagering at U.S. racetracks in 2012, is the third most popular form of equine racing after thoroughbred and standardbred racing, and quarter horses also are prized in rodeo events for their athleticism.

The acceptance of clones into the quarter horse registry would be the most-visible victory to date for backers of the technology, but the cloning of animals for food and sport is growing by leaps and bounds.

The FDA concluded in January 2008 that meat and milk from cow, pig and goat clones and the offspring of any animal clones are safe, opening the door to the commercial sale of such products, which are now both widespread and unlabeled.

Equine clones or their offspring are expected to appear before the year is out in other equine sporting venues – including non-breed specific rodeo competitions like barrel racing and reining, polo matches and equestrian events leading up to the 2014 Olympics, according to supporters of the technology.

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