Jockey Club Stewards Continue Study of Mares Bred Cap

The Jockey Club board of stewards announced Dec. 16 it will continue its consideration of a rule to limit the annual breeding of individual stallions.

In September, the stewards requested industry feedback on a proposal to cap the number of mares bred per stallion to 140. Motivating this change is a concern about the long-term affects of a relatively small number of stallions breeding an increasing percentage of all mares bred. In 2019, 43 stallions bred books of 140 mares or more and the mares this group of stallions collectively covered accounted for 25% of all mares bred in North America.

"The combination of these changes has resulted in a substantial increase in the percentage of foals produced by a discreet segment of stallions—signaling a worrisome concentration of the gene pool," the stewards said in a statement announcing the proposal.

"We are grateful for the many thoughtful comments in response to our September proposal," said a Dec. 16 statement from The Jockey Club. "The stewards are considering those comments as we continue to study the cause and effects of decreasing diversity of the Thoroughbred gene pool and finalize a rule to protect the breed's health and welfare."

The Jockey Club proposal recommended a phased-in approach as follows:

• Stallions entering stud service for the first time in 2020 would be exempt from the 140 limit through the 2023 season;
• Stallions that entered stud service in 2019 would be exempt through the 2022 season;
• Stallions that entered stud service in 2018 would be exempt through the 2021 season;
• Stallions that entered service in 2017 or prior would be subject to the 140 cap as of January 1, 2021.