SOME 44% of all the mares covered in Kentucky in 2021 visited one of the 40 busiest stallions in the state, and in the whole of the USA. Those 40 stallions represent just 20% of all the sires standing in the state.

Three of the four busiest stallions stand at Spendthrift, and three of the four are sons of Into Mischief. He also stands at Spendthrift and covered 214 this year. Into Mischief’s son Goldencents covered 230 mares, one more than Authentic, while Ashford Stud’s Practical Joke was third on the list with a book of 223 mares.

Six of the 10 busiest stallions in 2021 in the USA are at Spendthrift, while Ashford is home to six of the top 15. A total of 40 stallions covered in excess of 150 mares, and they are based at Spendthrift (11 sires), Ashford (9), WinStar (4), Lane’s End (4), Jonabell (3), Hill ‘n’ Dale (2), Taylor Made (2), Three Chimneys (2), Gainesway (1), Airdrie (1) and Darby Dan (1).

Kentucky-based stallions covered 60% of all the mares bred in the USA in 2021, a slight increase on the previous year. Authentic in second place and Vekoma who is fourth on the rankings were both covering their first book of mares.

This could be a thing of the past should the Jockey Club’s rule limiting sires to books of no more than 140 be implemented in due course.

The busiest stallions standing outside Kentucky were Honest Mischief (Into Mischief) in New York who covered 127 mares, while the former Tally-Ho Stud stallion Sir Prancealot (Tamayuz) covered 125 mares in California.