Fact of the Week: “One for the Ages”

There have been numerous studies on the effects of both paternal and maternal age on the racing class of their progeny. And we know that both sire and dam tend to produce their best progeny when young. This can be seen in our chart of American sires over the past 25 years where a consistent fall in stallions' average Beyer per crop can be seen as the sires' age creeps up. However, it is a general rule and certainly doesn't apply to all thoroughbreds. Elite sires seem to resist this fall and remain consistent right up to about age 18. A consistent supply of young high-class mares certainly helps. Moreover, a stallion's ratios beyond that point are still often well ahead of his younger counterparts. The difficultly here is deciding when a stallion falls below an acceptable level, made all the more problematic by the fact that proof of ability doesn't arrive until four or five years after covering your mare.