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12-11-2022, 10:01 PM
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#1
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Registered User
Join Date: Jun 2004
Location: Denver, CO
Posts: 285
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Evidence of maternal and paternal age effects on speed in thoroughbred racehorses
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12-12-2022, 04:41 PM
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#2
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Registered User
Join Date: Mar 2005
Location: Queens, NY
Posts: 20,597
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The math is over my head, but right away I wonder if they had a good way to control for quality?
For example, it's likely that Flightline is going to get a lot of very high quality mares to breed to in the early years, especially if the first crop looks good. But by the time he reaches a certain age, even if he still active, the quality of the mares will probably decline. The highest quality ones will move on to the latest hot sire. I'm sure the same is true for the very best mares. That alone would impact the speed of the offspring. You'd have to control for that. It could almost be a self reinforcing outcome where if so and so is 15, they stop sending him the best mares, he produces slower horses, so they end him even lower quality mares etc..
__________________
"Unlearning is the highest form of learning"
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12-13-2022, 01:24 PM
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#3
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Registered User
Join Date: Feb 2017
Location: Tampa Bay
Posts: 1,100
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Quote:
Originally Posted by classhandicapper
The math is over my head, but right away I wonder if they had a good way to control for quality?
For example, it's likely that Flightline is going to get a lot of very high quality mares to breed to in the early years, especially if the first crop looks good. But by the time he reaches a certain age, even if he still active, the quality of the mares will probably decline. The highest quality ones will move on to the latest hot sire. I'm sure the same is true for the very best mares. That alone would impact the speed of the offspring. You'd have to control for that. It could almost be a self reinforcing outcome where if so and so is 15, they stop sending him the best mares, he produces slower horses, so they end him even lower quality mares etc..
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They sort of address that phenomenon albeit not directly. From the article…
“Specifically, if high sire quality is erroneously inferred from strong early life performances by a truly average sire, then increasing age brings more data and the estimated merit of that sire will decline towards the mean. In this study, we avoid this potential source of bias by analysing all sires represented irrespective of perceived (or actual) quality.”
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12-13-2022, 08:56 PM
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#4
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Registered User
Join Date: May 2010
Posts: 2,021
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Admittedly I did not read the study yet.
But I recall the wisdom being...the older the mare, the more successful the offspring. Meaning a mares foals later in her life are better than her first borns.
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12-14-2022, 09:18 AM
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#5
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velocitician
Join Date: Aug 2004
Posts: 26,278
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EVERY OVUM produced by any female, was created when they were still a fetus, so on the distaff side of the coin,that is a long time for free radicals to do their damage.
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"If this world is all about winners, what's for the losers?" Jr. Bonner: "Well somebody's got to hold the horses Ace."
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12-14-2022, 11:17 AM
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#6
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Registered User
Join Date: Jun 2019
Location: Clarksville, AR
Posts: 1,215
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Quote:
Originally Posted by 46zilzal
EVERY OVUM produced by any female, was created when they were still a fetus, so on the distaff side of the coin,that is a long time for free radicals to do their damage.
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Glad for whatever damage those free radicals did to the ovum 17 year old Somethingroyal conceived with in 1969!!!!!
__________________
Tom in NW Arkansas
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”Past performances are no guarantee of future results.” - Why isn't this disclaimer printed in the Daily Racing Form?
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