Report of Mares Bred Indicates Steady Activity in 2021

Based on Report of Mares Bred statistics released Oct. 25 by The Jockey Club, there was little difference in the number of mares covered in 2021 compared with this point last year.

Based on reports received through Oct. 18, The Jockey Club Report of Mares Bred says 27,829 mares have been covered in North America in 2021. Compared with last year that figure is steady—down less than 1% from the 27,970 mares reported covered through Oct. 18, 2020.

Following the recent trend, those mares were covered by fewer stallions. Again based on reports through Oct. 18, the RMB said 1,016 stallions covered mares in 2021, down 4.8% compared with the 1,067 in last year's report through Oct. 18, 2020.

As final reports come in, The Jockey Club estimates an additional 2,500 to 3,500 mares will be reported as bred during the 2021 breeding season.

Twelve stallions bred more than 200 mares during the 2021 season led by Spendthrift Farm's Goldencents, a son of the farm's leading sire Into Mischief and a top 20 sire this year by progeny earnings.

Goldencents   bred 230 mares this year, which was a 13% increase from his 2020 book of 204 mares. The stallion is North America's leading fourth-crop sire by progeny earnings ($6.8 million), by number of winners (130), number of black-type winners (six), and by number of black-type performers (18). By cumulative results, he is the leaders of his sire class by winners (216), black-type performers (37), and tied with Airdrie Stud's Cairo Prince   by career graded/group stakes winners at five.

Spendthrift stands six of the stallions that bred 200 or more mares this year. The others include first-year sires Authentic   (229) and Vekoma   (222) along with Omaha Beach   (215), two-time leading sire Into Mischief   (214), and Mitole   (208).

Ashford Stud stands four in the top 12 sires by mares bred: Practical Joke   (223), Munnings   (217), American Pharoah   (204), and Mo Town   (204). Ashford's Uncle Mo, who topped the mares bred list in 2020 at 262 mares, bred 189 mares this year.

Hill 'n' Dale at Xalapa has one sire, Maclean's Music  , among the top 12 with 221 mares bred, and Gainesway has one, McKinzie  , who bred 214 mares.

The number of North American stallions breeding 100 or mares fell this year, from 90 to 78, while the number of stallions breeding 200 or more was unchanged from 2020.

RMB statistics for all reported stallions in 2021 are available through the Fact Book section of The Jockey Club's website at jockeyclub.com.

Kentucky traditionally leads North America in Thoroughbred breeding activity. During 2021, Kentucky's 200 reported stallions covered 16,727 mares, or 60.1% of all mares reported bred in North America. The number of mares bred to Kentucky stallions increased 2% percent compared with the 16,391 reported at this time last year.

Of the top 10 states and provinces by number of mares reported bred in 2021, stallions in Kentucky, California, Ontario, and Indiana covered more mares in 2021 than in 2020 (as reported at this time last year). 

The following table shows the top 10 states and provinces ranked by number of mares reported bred in 2021:

Note: Each incident in which a mare was bred to more than one stallion and appeared on multiple RMBs is counted separately. As such, mares bred totals listed in the table above may differ slightly from counts of distinct mares bred.

In addition, RMB information on stallions that bred mares in North America is available through report 36P or a subscription service at equineline.com/ReportOfMaresBred.