Jockey Club backtracks on thoroughbred stallion breeding limits

The rule limiting stallions born from 2020 onwards from breeding more than 140 mares was adopted in May 2020 amid concerns around the narrowing of the diversity of the Thoroughbred gene pool in the US.
Photo by Gene Devine

The Jockey Club in the US has rescinded a rule that would have restricted younger Thoroughbred stallions from breeding with more than 140 mares each year.

Rule 14C of The Jockey Club’s Principal Rules and Requirements of the American Studbook stated that “The total number of broodmares bred per individual stallion whose year of birth is 2020 or thereafter shall not exceed 140 per calendar year in the United States, Canada, and Puerto Rico. The Jockey Club shall limit the number of Stallion Service Certificates for such stallions to a maximum of 140 per calendar year.”

The rule was proposed in September 2019 and adopted in May 2020 following extensive public comment, amid concerns around the narrowing of the diversity of the Thoroughbred gene pool in the US. The rule did not apply to stallions already standing at stud.

In a statement on Thursday, Jockey Club chairman Stuart S. Janney III said the board of stewards had rescinded the rule after concerns that the reaction to the rule might “divide the industry at a time when there are many important issues that need to be addressed with unity”.

“We are taking this action for the greater good of the entire industry. The Jockey Club remains committed to the sustainability and welfare of the breed and will continue to invest in programs and research that will bolster and support the industry in the years to come,” Janney said.

One of the drivers of the rule change was a scientific study showing an increase in inbreeding in Thoroughbreds between 1996 and 2006, during which the number of stallions covering 100 or more mares jumped from 14 to 128.

In 2007, 5894 mares (9.5% of the total) were bred by stallions that covered more than 140 mares. By 2019, 7415 mares (27% of the total) were covered by stallions with books of more than 140, a threefold increase.

In the 2021 season, some 45 stallions, all in Kentucky, bred more than 140 mares, with Practical Joke topping the list at 231 mares bred.

A lawsuit early last year led by three major Kentucky horse farms labeled the rule an anti-competitive restriction and argued that it threatened to disrupt the industry. B. Wayne Hughes, of Spendthrift Farm, said at the time: “If they can limit the number to 140, what’s to stop them from limiting it to 100 or 80 or any other number down the road? What if your mare isn’t one of the 140? We are really concerned about the small breeder’s ability to survive this.”

The Jockey Club said it would continue to maintain The American Studbook’s Principal Rules and Requirements in keeping with its mission to ensure the health of the Thoroughbred breed.

• Receive a notification when a new article is posted:

Latest research and information from the horse world.

One thought on “Jockey Club backtracks on thoroughbred stallion breeding limits

  • February 22, 2022 at 5:06 am

    Gee, what a shocker. Very disappointing yes unsurprising decision by TJC. Just further illustrates that they don’t have the best interest of the horses or the breed at heart. Some of these stallions are breeding so often that they have to be given IV fluids and other recuperative care.


Leave a Reply

Your email address will not be published. Required fields are marked *