Breeding for Structural Correctness

Breeding for Structural Correctness

Earnings and accolades shouldn’t eclipse conformation faults when making performance horse breeding decisions.

Two young horses stand in a grass pasture.

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The American Quarter Horse Journal logo

By Julie J. Bryant and Tara Matsler

While horses have been bred for specific purposes for thousands of years, the specialty breeding for specific show events is relatively new in American Quarter Horses, having started only a few decades ago. For a horse to fulfill any job well, logic demands it should be structurally correct as defined by the breed and the physical challenges of the sport. 

For multiple National Reining Horse Association Futurity champion trainer Casey Deary, a horse with good conformation for his chosen sport is one that catches his eye. 

“I don’t even look at the papers until after I look at the horse,” he says, glancing toward a group of riders working on his outdoor pad in Weatherford, Texas. “Like that buckskin over there. He catches my eye, and that’s something important in this sport. But, if he’s not made to do the work, then I would have to pass on him.”

Specialized horses sometimes have different conformation traits that help them perform a specific skill with more finesse. 

“With breeding, we’ve already got in mind what the horse will be doing: Maybe it’s a cutter, a reining horse or a racehorse,” says Chris Benedict, an AQHA judge and manager of DLR Stallion Station in Weatherford, Texas. 

“We have a lot of pretty, well-bred horses these days that are really good at what they do,” Chris says. Most importantly, though, you want a horse to be good in all senses.

Occasionally, Chris notes, you’ll find a horse with a conformational fault that manages to outperform its peers. Horses like that are not built for the long haul or intense work.

Structural incorrectness typically means a longer training period if only to determine if the horse is capable, resulting in a higher investment. Furthermore, the likelihood that the flaw could be passed on should nix any chance that the horse could have a breeding career.

“Our industry doesn’t work anymore like it did before,” says Dr. Kurt Harris, managing veterinarian of Stonewall Equine Rehabilitation and Fitness and owner of 2006 AQHA Superhorse RS Lilly Starlight. “People don’t necessarily take a horse out of their breeding program because of a structural issue.”

Dr. Harris, a veterinarian for more than 30 years who has also bred champion racehorses, notes there’s been a change in dynamic from selecting a horse based on conformation to current selections being based on its sire's or dam’s performance record.

Many times, breeders don’t put enough stock in the fact that a stallion or mare was “unshown due to injury.” Chris and Dr. Harris both warn that career-ending injuries often are the result of poor conformation. 

“The market today looks at horses based on their performance records and how much they’re winning,” Dr. Harris says, “and not if the mare and sire are both sickle-hocked or have other issues.”

It makes sense why sickle hocks, in particular, are often found in performance horses, says Dr. Harris. Yet it certainly is not a trait breeders should breed for. 

“If a horse is sickle-hocked, obviously its feet are underneath him a little more and it will be easier for him to stop than a horse whose hocks are out behind him,” Dr. Harris says. “But you can’t select horses for that when breeding because it will catch up with you in the long run and get worse and worse in future generations.”    

horse that is slightly 'behind' at the hocks

This horse's hocks are slightly behind him. It’s not a deal-breaker, but the horse might experience more stress in the stop. (Credit: Julie J. Bryant)


A horse that is sickle-hocked will often compensate for that fault through its stifles or back, says Dr. Harris, resulting in problems there. Arthritis very commonly appears at an early age in horses with those issues.

“When you have a horse that is sickle-hocked, you’re putting more pressure on the tarsal bones and you’ll see horses that get arthritic earlier,” he says. “If both lower joints are fused, then sometimes those horses will get sore stifles. There really is no other way to see that than through X-rays.”

horseman demonstrates imaginary line to illustrate sickle- or cow-hocked horse

Drop an imaginary or real line from the horse’s hip to the ground to see if it’s sickle-hocked or camped under. (Credit: Julie J. Bryant)


Learning how to identify structural issues during a cursory visual assessment is easily addressed. AQHA provides resources to owners and potential buyers that will help them spot any structural issues, including its free e-book, Buyers Guide to an American Quarter Horse, as well as Structure In Detail, free to AQHA members.

These experts agree that, while sometimes we buy a show horse with structural flaws if their ability and training warrant it, horses with structural issues should be avoided as breeding options.