Secretariat and Buckpasser

[stancaris]

Pan Zareta wrote: that imprinting explains why Buckpassers daughters progeny performed so well and gave him such a high AEI as a BMS.

Then do you now say that Bold Rulers super autosomal variants were turned off in his daughters and they could not transmit them to their progeny?

All these great genetic gems with nowhere to go?

Imprinting is another hypothesis to explain BMS success but surely it's not the only explanation.

Males have nothing on their Y chromosome to suppress traits on the X.
X linked traits are important.

[DDT]

Stan

I have no idea why you want to bring Bold Ruler into this discussion, he is the perfect example of using caution when judging success on the basis of progeny earnings in the stud. A lot of people think of Bold Ruler as a great sire, but when you examine the stats it is clear that he was an exceptional sire of 2 year olds but once they turned 3 they were not as successful. Secretariat is the only Bold Ruler sired champion 2 year old that went on to championship honors at 3 years of age. Bold Ruler sired one older champion male, Bold Bidder and one older female champion in Gamely, who was voted champion older female 2 years in a row. To put it as simply as I can, Bold Ruler would be almost dead in the water as a tail male ancestor if not for his Seattle Slew/A.P. Indy connection. I do not believe his genes were all powerful as you claim and he received a lot of help from the mares he covered.

I have agreed with you all along that Buckpasser in an X passing position is a plus and his stats will be hard to beat as a broodmare sire, however I do believe that Storm Cat or A.P. Indy or both of them have a shot at surpassing his record.

Maternally imprinted genes are the primary factor for broodmare success, not genes carried on the X.

DDT

[Pan Zareta]

Pan Zareta wrote: that imprinting explains why Buckpassers daughters progeny performed so well and gave him such a high AEI as a BMS.

That's not what I said. I said it seems to be the scenario that best fits with available evidence. If you're going to quote me do it verbatim or not at all.

Then do you now say that Bold Rulers super autosomal variants were turned off in his daughters and they could not transmit them to their progeny?

All these great genetic gems with nowhere to go?

Implicit in the remarks above is the premise that different alleles (variants) in a single gene are wholly responsible for broodmare sire success/failure. That's pretty naive. Genetics is not the only factor involved. Furthermore, that success/failure is ultimately defined by daus. progeny earnings and elite racing performance is indisputably a very polygenic 'trait'.

In other words, the genetics of what you perceive as Bold Ruler's "failure" as broodmare sire doesn't necessarily involve the same variables as Buckpasser's success.

[stancaris]

DDT asked: Why did I bring Bold Ruler into this discussion?

I looked at his stats as a sire and broodmare sire and was amazed by the difference.

As a sire Bold Ruler was excellent. In the book--Racehorse Breeding Theories by Frank Mitchell on page 72 Bold Ruler is the absolute top of the sire list regarding AEI with an index of 7.73. All the sires to that date that were lower than him (indices of 5.21 and lower) included such greats as Alydar, Northern Dancer, Mr. Prospector, Seattle Slew, Ribot etc.

Bold Ruler's AEI as a broodmare sire was 1.96. So here we have a sire that has an AEI that is more than 3 times greater than his AEI as a broodmare sire.

One explanation of the above is that Bold Ruler's X chromosome was not as good as many of his autosomes which certainly carried genetic gems.

How do you account for Bold Ruler's big difference in AEI as a sire (7.73) and as a broodmare sire (1.96)?

Could the X passing position have anything to do with it?

[DDT]

Stan

As I previously stated, Bold Ruler had wonderful stats that were primarily garnered from the efforts of his 2 year olds, and not from efforts of his 3 year olds and up. He was a great sire and speed influence. His AEI as a broodmare sire is much lower because he contributes only an average of 25% to the mix and his daughters progeny did not win enough to raise the AEI. You also must remember that the AEI as a stallion is a direct result of his 22% stakes winners from foals. I hope this will help in answering the question regarding the reasons for the big difference in the AEIs.


DDT

[stancaris]

DDT: In my estimation you have not provided an explanation for the differences in Bold Rulers AEIs as a sire and BMS.

Furthermore, of the 11 champions that Bold Ruler fathered, 5 of them were champions at age 3: Lamb Chop -3 year old filly champ of 1963, Bold Bidder who won the 10 furlong Monmouth Handicap was the 3 year old champion of 1966, Gamely the champion older mare of 1968 and 1969, Wajima the champion 3 year old of 1972 and Secretariat, HOY in 1972 and 1973. 5 of 11 being champions at age 3 and beyond is not an indicator that Bold Ruler was primarily a sire of 2 year old champs.

You said, Bold Ruler contributes only an average of 25% to the mix.

That statement is true of all Broodmare sires--they all contribute on the average 25% of their autosomal genes to the mix. One important side note you failed to mention: A broodmare sire contributes 50% of his X chromosome on the average to all of his daughter's progeny.

Then you go on to say that his daughters progeny did not win enough to raise the AEI. Well that tells us nothing about WHY they did not win enough? What genetic traits did they lack? Does the X chromosome have anything to do with it?

Then you go on to say that Bold Ruler's AEI as a stallion is a direct result of his 22% stakes winners from foals. I could be wrong but I thought that 7.73 AEI came from all 356 foals not just from his stakes winners. Maybe someone here can clarify this point.

I believe the big difference in his AEI as a sire (7.73) and his AEI as a broodmare sire (1.96) was due to his X chromosome being somewhat inferior. He is not often found in the X passing position of Derby winners and Derby place finishers over the last 41 years whereas the great broodmare sire Buckpasser is found in the X passing position frequently. Remember I pointed out the score being 13 to 3 in favor of Buckpasser with regard to winners and place finishers in the Ky Derby. I believe similar results would be found in the Preakness and Belmont stakes but I would have to research that to be sure.

[DDT]

Stan

What I said was that Secretariat was the only 2 year old Champion sired by Bold Ruler to win a championship as a 3 year old or older not that Bold Ruler sired no 3 year old or older champions. Why do you continue to edit posts. The 22% stakes winners from foals earned a lot of money. 2 stakes winners out of every 10 foals tends to produce a high AEI. Try reading my poorly worded posts before you edit what I wrote.


DDT

[stancaris]

Pan Zareta: How do you explain the big difference in Bold Ruler's AEI as a sire (7.73) with that of his AEI as a broodmare sire (1.96)?

[Pan Zareta]

Pan Zareta: How do you explain the big difference in Bold Ruler's AEI as a sire (7.73) with that of his AEI as a broodmare sire (1.96)?

Obviously, the polygenic profiles of the offspring of Bold Ruler and his very well-bred consorts must have been extraordinarily favorable for the racing environment of the time whereas those of his daughters' produce (and sons' progeny) were 'merely' better to much better than average. More or less the reverse is true of Buckpasser although the differential his between sire and broodmare sire AEI was not as marked.

If you think a single gene or even a single chromosome explains these facts, you're nuts, not to put too fine a point on it. If you want to home in on one to begin the discussion it would be ECA18, not ECAX. You'd realize that if you bothered to familiarize yourself with the publicly available TB genome-based information, or at least review and assimilate the genome-based facts provided to you 2-1/2 years ago in 'The Mares in Great Sires' thread.

Instead, you comb through records looking for circumstances you believe confirm your false premise and return here regularly, ignoring/denying/mis-paraphrasing the genome-based evidence, to have another go at making a heavily cherry-picked circumstantial case for the X being the über chromosome of broodmare sire success. This time it's Bold Ruler, Buckpasser, and the last 41 KD winners.

Needless to say, when all pedigree positions are considered Bold Ruler turns up more than twice as frequently as Buckpasser in those pedigrees. Buckpasser actually turns up there every bit as often in non x-passing position as in x-passing. Moreover, when he does appear in KD winner x-passing positions it's never in the 50%-by-default x contributing 1st broodmare sire position. In fact, he doesn't even appear in the first 5 generations of Orb's pedigree.

[stancaris]

Pan Zareta: In the Mares in Great Sires thread on Oct 25, 2011 at 1:38 PM my statement was as follows: Assuming that the X chromosome does not carry a gene for heart size, it still is a powerful carrier of super genes because these super genes on the X make a broodmare sire successful.

Byron Rogers responded to the above statement by saying, "I think I said from my first post on this thread that there are important variants on the X chromosome for performance. Not sure I would call them "super genes" but I would call them "important alleles."

Mr. Rogers does not agree with your take on the X chromosome which is as follows---- that at best the X chromosome only plays a minor role in broodmare sire success. If you really believe in that your "nuts".

You have so conveniently avoided answering my question above with references to polygenic profiles of Bold Rulers offspring which prove nothing. Bold Ruler was bred to great mares like Buckpasser and yet never led the Broodmare sire list. His fantastic autosomes could not help him reach that level even for one year despite generating twice as many black type daughters as Buckpasser.

[Pan Zareta]

You're parsing the remarks of others. Again. To your own advantage. Again. Shall I post the proof of that or can we skip that step this time?

[stancaris]

Pan Zareta: According to you the X chromosome at best plays only a minor role in broodmare sire success. That's ridiculous. Byron Rogers calls the variants his company discovered on the X chromosome that relate to elite performance "important alleles". He would not call them important alleles if they only played a minor role at best in broodmare sire success.

I am still waiting for a reasonable answer as to why Bold Ruler has a 7.73 AEI as a sire and a much lower 1.96 as a broodmare sire. You have so conveniently avoided answering that question. Despite having twice as many black type daughters as did Buckpasser, Bold Ruler NEVER led the broodmare sire list. Could the X chromosome have something to do with this glaring difference in AEIs? Bold Ruler's X was just not good enough to get him to the top of the broodmare sire list.

Then you go on to say that Bold Ruler appears more often in pedigrees than does Buckpasser. Thats true but it proves nothing in regard to this discussion which revolves around your deluded contention that the X chromosome at best plays only a minor role in broodmare sire success. You can cite whatever you want by way of articles but there has never been any proof of that self serving idea of yours that the X only plays a minor role in BMS success.

Finally, Buckpasser had a tremendous influence on the breed through his daughters. He led the BMS list 4 times and all his daughters received nearly 100% of his X chromosome and they transmitted on the average 50% of that X to all their offspring.

37% of the top 10 leading broodmare sires over the last 6 years have Buckpasser in the X passing position. 3 of them have Buckpasser as their broodmare sire (Woodman and Miswaki and Seeking the Gold), 2 of them have Buckpasser as their second damsire (Danehill and AP Indy) and one of them has Buckpasser as his third damsire (Unbridled). These top ten leading broodmare sires over the last 6 years may not seem like evidence to you but surely there is something beneficial going on with the X chromosome because all of the above received part of Buckpasser's X.

[hpkingjr]

Buckpasser's third dam was La Troienne, probably the most influential mare in history. La T loves La T. Is it possible that she is the secret to Buckpasser's success? Stacking La T. has created many outstanding race horses.

From a practical standpoint, Buckpasser didn't produce many breeding sons, Bold Ruler did. Almost every stakes winning son of Bold Ruler hit the breeding shed. Now you couldn't breed the Bold Ruler mares back to a Bold Ruler line stallion, at least in the first 3 or 4 generations. Buckpasser mares didn't have that problem. They could be bred to almost any stallion. Did this affect the sire stats?

[Pan Zareta]

Buckpasser's third dam was La Troienne, probably the most influential mare in history. La T loves La T. Is it possible that she is the secret to Buckpasser's success? Stacking La T. has created many outstanding race horses.

From a practical standpoint, Buckpasser didn't produce many breeding sons, Bold Ruler did. Almost every stakes winning son of Bold Ruler hit the breeding shed. Now you couldn't breed the Bold Ruler mares back to a Bold Ruler line stallion, at least in the first 3 or 4 generations. Buckpasser mares didn't have that problem. They could be bred to almost any stallion. Did this affect the sire stats?

Buckpasser definitely owes some of his success to being bred back to LaT's family. That yielded the outstanding runners/producers Numbered Account and Relaxing, some other b/t runners, and Playmate, dam of Woodman.

Excellent point about the number of sons Bold Ruler got in the stud. His 'tail male' descendancy is pretty contracted now but he had so many successful sons in the stud that it may be unreasonable to expect to see as many of his daus. in contemporary pedigrees as daus. of more modestly successful sires. Whether that has any bearing on the difference between his AEIs as sire and broodmare sire is hard to say. It would be interesting to know how his broodmare sire AEI compares with the average sire AEI of his sons.

[Pan Zareta]

Pan Zareta: According to you the X chromosome at best plays only a minor role in broodmare sire success. That's ridiculous. Byron Rogers calls the variants his company discovered on the X chromosome that relate to elite performance "important alleles". He would not call them important alleles if they only played a minor role at best in broodmare sire success.

Stan, here are his verbatim replies to you when you engaged in similar overstatement about the importance of the x on two occasions during 'The Mares in Great Sires' thread. I see no support here for the idea that the x is of more than minor relevance to elite performance and therefore broodmare sire success.

page 4, 'The Mares in Great Sires' thread, 20 Oct 2011

brogers:

1) you said there are variants on the X chromosome that relate to elite performance. It seems to me that this supports the idea of superior broodmaresof sires like Buckpasser, Dr. Fager, hoist the flag etc. These stallions were famous for getting super daughters who in turn got great runners both sons and daughters. Main point... The x chromosome is vital to the overall success of racehorses.

Yes there are variants on the X chromosome that relate to elite performance

But they are far from "vital to the overall success of racehorses"

We have identified 37 SNP variants across 19 sites on the genome that separate out elite performance from non elite. The variant that reached statistical significance (P value) on the X chromosome is one of these 37 SNP's.

The problem is that when you rank them for relevance, the SNP on the X chromosome is not in the top 10 as far as importance is concerned. There are significantly more important SNP's in terms of performance, that are located on other chromosomes. You are over-rating the variant on the X Chromosome.

page 12 'The Mares in Great Sires' thread, 20 Nov 2011.

Performance is related to the X chromosome according to Byron Rogers and the company he works for.

Stan,

Let's not overstate the case.

1) We found that there are variants within genes on the X Chromosome that appear in elite horses against non-elite.

2) We also found that there are 18 other sites across 9 other chromosomes that also have variants within genes that appear in elite horses against non-elite.

3) The variants that appear on the X, in terms of influence, do not appear to be as important as others. There are variants on the 18 Chromosome for example are significantly more important when it comes to elite performance than any variant appearing on the X.

Haun told a good story. But it was a story. She made a link between heart size, a long dead mare and the X Chromosome that is just not there.

If she had stuck to proving cardiovascular capacity has an impact on maximal oxygen uptake, she would have been right.

If she had stuck to providing evidence that there are variants within genes located on the X chromosome that have an influence on performance she would have been right.

She took a leap and incorrectly tied the two together with a mystical story about a long dead mare in Pocahontas. That was wrong and has done more to mislead breeders in recent history than any other theory.