Heritability in Japanese Thoroughbreds

[brogers]

A new paper has been released on the heritability of performance in Japanese thoroughbreds. I have put together a post on it and linked the paper.

http://performancegenetics.com/2012/01/ ... /#more-373

[NORTHSTAR1]

xy matched with xy -----makes xx --xy---yx---yy ------25%

take out the loser horses ie remove one of the above and the heritability jumps to 33%

[xfactor fan]

The Japanese data supports the idea that the racing class of the mare makes a huge difference.

Think about the dynamics of selection. In racing TB's the males face huge selection pressure. First they have to escape the gelding knife. Then they have to have enough racing success to be considered worth breeding.

Mares don't face the same pressure. A well bred filly that can't run can be retired and spend her life as a broodmare. The selection is mild, and is actualy selecting for her sire, or dam.

Dropping out non winners, probably doesn't affect the pool of stallions. However it makes a huge change in the mare population. It selects against unraced, and non winning mares, leaving only mares that have had some success on the track.

[Bast]

Mares don't face the same pressure. A well bred filly that can't run can be retired and spend her life as a broodmare. The selection is mild, and is actualy selecting for her sire, or dam.

Dropping out non winners, probably doesn't affect the pool of stallions. However it makes a huge change in the mare population. It selects against unraced, and non winning mares, leaving only mares that have had some success on the track.

All true...but...this would have led to the culling of La Troienne and Somethingroyal.

[Patuxet]

In dismising speed figures as a rational measure of performance Byron's post states: "Formal Gold at a peak Beyer of 126 should be a much better stallion than A.P Indy at 114!"

I pay scant attention to speed figures but I'm surprised that A.P. Indy's Belmont in 2:26.15 -- third fastest after Secretariat and Easy Goer -- wouldn't have been worthy of a higher Beyer than that.

[xfactor fan]

Bast,

Point taken about culling non winning mares. I was going to mention Somethingroyal. Which leads to the question, was she slow, late maturing, or didn't like the track surface? Or was she more valuable as a broodmare than taking the time to keep her in training?

Knocking out all non-winning mares lumps everything together, unraced, slow, difficult, or late maturing. In this class there are going to be mares that turn out to be good producers.
However, it doesn't change the fact that when these mares are taken out of the study, racing performance figures change, indicating that the offspring of winning mares out perform, offspring from non-winning mares.

[Bast]

Bast,

Point taken about culling non winning mares. I was going to mention Somethingroyal. Which leads to the question, was she slow, late maturing, or didn't like the track surface? Or was she more valuable as a broodmare than taking the time to keep her in training?

Knocking out all non-winning mares lumps everything together, unraced, slow, difficult, or late maturing. In this class there are going to be mares that turn out to be good producers.
However, it doesn't change the fact that when these mares are taken out of the study, racing performance figures change, indicating that the offspring of winning mares out perform, offspring from non-winning mares.

But a lot of these unraced/disappointing fillies given a chance as broodmares are failures. Perhaps individual breeders on the ground know enough about their own stock to know when not to cull, at least, not right away.

[xfactor fan]

It might be interesting to filter the data a bit more and see what comes out.

There's a huge jump when mares are divided into winners/non winners.

Looking at winners, losers, and unraced might be useful.

I can't figure out any other way to sort the mares into sub-groups. Anyone have thoughts on this?

[vineyridge]

La Troienne raced and lost. So did Aloe.

I don't know what Catnip's race record was, but I do know that if it existed, it couldn't have been good.

Think where the modern TB would be without those mares.

For groupings, how about:
winners with inflation adjusted earnings over?
winers with inflation adjusted earnings under ?
mares with earnings but with inflation adjusted earnings under ?
unraced
All others

The earning stats are already being kept.

[bdw0617]

I think a lot of mares, that if were forced to race because they had to win, could have went on and won sooner or later. Mares/Fillies tend to get a shorter leash than colts/geldings do. If they are high class and dont' show instantly that they are very good / shed.

I don't think La T was a bad horse neither was somethingroyal, she just wasn't good enough to win without some races under her belt, which she never got. In somethingroyals case she probably wanted a hell of alot more ground that she was being given, and I don't know if she was raced on turf or not but I would imagine she would love the turf.

[Joltman]

When distinct horses are brought up (SR, LaT) there will always be exceptions. But the statistics are based on much larger pools and averages/medians etc. which over the whole pool point to racing class as important. Often, for an individual there may have been mitigating circumstances - relating to the horse or not. So, all those horses ready to run in 1911 with no where to go would have had their opportunities seriously limited. One could probably study certain eras as well, like market conditions in 1930, or regional racing conditions eliminated the possibilities of running.

jm

[bdw0617]

that doesn't even include mares like.. magnificence, who, anyone with 2 eyes could see she was a legit grade 1 caliber filly as aa 3YO but was very mismanaged after the switch to synthetics, so all she has is a misley grade 3 win by beating silver swallow in the santa paula.

I believe to some extent, actually to more than some extent that race horses produce race horses more than blood lines do. but every horse has to be judged on it's own individual merits and circumstances.

[Jeff]

Mares that did win and did produce winners are most likely to be owned by those most able to give a horse opportunity to prove itself at the track.

Mares that did not run or did not win a race are more likely to be owned by owners who lack the means to give the mare's offspring the best opportunity to excel.

Seems fairly simple. Black type or not speaks as much about the financial resources of the owners as much as about the horses.


I would imagine that even in Japan, the richest people own the best horses and they are more likely not to own mares that did not race or did not win.

It's to be expected that mares that did not race are not going to produce as well as mares that did race and win.

But often times the mare that did not race or did not win, she still puts out a runner that beats the best of the rest.

Of course, there's always somebody trying to beat down a poor old unraced mare or a mare that didn't win, but often times those mares produce very well anyway, but the averages are still with the mares with that did race and win, because she's most likely to be owner by deep pockets.

[vineyridge]

Just wondering.

Does anyone know Concertina's or Comic Song's racing record? I found a reference to the fact that none of Concertina's foals nine foals did well on the track. But she produced Plucky Liege and one of her daughters is the dam of Friar's Daughter. I do know Plucky Liege won 4 races as a 2 yo, but don't know what quality of races she won.

Which reminds me--was one of Tesio's secrets Spearmint daughters?

[CosMos]

Plucky Liege had thirteen race starts, winning four two-year-old races for earnings of £1,811
http://en.wikipedia.org/wiki/Plucky_Liege

Concertina was unraced. Check out her progeny here...
http://www.idshs.com.au/perl/search.pl?op=ssdesc&index=concertina&gens=5