“I’ve always maintained that inbreeding should be practiced only through superior performing animals in an effort to filter out negative recessives. That’s why, despite a lack of evidence, I’ve half-heartedly clung to the notion that stakes-winning broodmares bearing the Rasmussen Factor might proved to be somewhat better producers.”
I received the comment above from Allison about six months ago on my post “You Learn Something New Every Day.” Per his request, I investigated stakes-winning mares bearing the Rasmussen Factor (RF) as producers. Let us start with prices.
Category Foals Average Maverage Price Index
RF SW Dams 404 $64,521 202.22 1.31
I identified 404 foals among sales foals of 2008-2111 whose dams were both stakes winners and possessed RF. Their prices were slightly above the norms, as you can see above, which was to be expected from stakes-winning mares. Their prices were slightly lower, however, than the prices for all 6,659 foals out of stakes-winning mares (average of $85,050, maverage of 222.66, Price Index of 1.45).
The chart below shows results for these 404 foals. APPPSW stands for average Performance Points per stakes winner, the benchmark now being 701.
Category Foals SWs % APPPSW PPI (Result)
RF SW Dams 404 20 4.95 780 1.62
The RF group had very nice results, a PPI of 1.62, well above their price of 1.31, as demonstrated in the chart below.
Category Foals Price Index PPI (Result) Difference
RF SW Dams 404 1.31 1.62 +0.31
This appears to be a clear-cut victory for the RF group. But the 6,659 foals out of all stakes winners also had very similar prices and results, as summarized below.
All SW Dams 6,659 1.45 1.74 +0.29
The 404 foals had a difference of +0.31. All 6,659 foals out of stakes-winning dams had a difference of +0.29. The latter group had a price 0.14 higher than the former group (1.45 to 1.31). The latter group had a result 0.12 higher than the former group (1.74 to 1.62).
If this were a football game, the score would be 31-29 in favor of the RF group. They won by a safety in overtime.
So it does appear that stakes-winning dams with the RF factor were slightly better producers than all stakes-winning dams, but the emphasis has to be on the “slightly.”