One Mile Is the "Stallion Maker"

[gumtree]

[QUOTE=Shammy Davis;8701490]
We yanks don’t have a clue when it comes to the progeny of our stallions. We put our colts to stud well before their potential is truly recognized. It is a total numbers game in the states. It is all about marketing derby crop colts. Very few American stallions cover enough mares to know what their progeny potential is on a race course. JMHO.[/QUOTE]

Not to be snarky but as they say across the pond, this is a bit if not a lot of rubbish.

[gumtree]

“No offense to Tesio, but that proclamation was made the better part of a century ago at this point”

Exactly, completely dated. I have never thought of him as the breeding guru that a lot of people seem to think he was. He also was in a unique situation having/owning the number of mares he did and the stallions to work with. Different time, different era.

[Shammy_Davis]

[QUOTE=gumtree;8702008]
Not to be snarky but as they say across the pond, this is a bit if not a lot of rubbish.[/QUOTE]

Explain?

[vineyridge]

Here’s the point about milers–at least in the past. If anyone still believes in Hill’s Speed Gene (absent the insertion at or near the same point that seems to have been developed in horses from the Americas), a horse could be homozygous for the speed variant (CC), it could be homozygous for the stamina variant (TT) or it could be heterozygous (CT). IIRC, almost all English stallions from the past whose DNA was tested lacked the C variant, which seems to have been widely spread with the import of horses from North America. Now the C variant is present in the vast number of modern TBs.

Milers have been good stallions for over a hundred years. It has been postulated that perhaps part of their appeal could be that the vast majority are heterozygous for the speed gene, which determines in part how muscles are developed and function in the adult horse. If a CT stallion is bred to a mare with a C allele, the odds are that there is a 25% chance of a CC offspring. If bred to a mare carrying a T variant, there is at least a 25% chance of a TT offspring. So a stallion who is heterozygous for the gene would be able to produce offspring at each end of the speed spectrum. And since the mile is neither a real sprint or a real distance, it has been postulated that the heterozygous racer would have an advantage, since it carries both the propensity for speed and for stamina.

However, I will say that this theory is based on older science. There may be new studies out there that I am not aware of that show something completely different (other than the existence of the specific insertion that has been proved to affect speed and is found primarily in horses with a background in the Americas).

[Shammy_Davis]

[QUOTE=gumtree;8702008]
Not to be snarky but as they say across the pond, this is a bit if not a lot of rubbish.[/QUOTE]

Rubbish is it? Well here is a 2011 study from across the pond (UK), that is the basis for my comment. Granted the subject of stallion selection and performance is a complicated one in the U S, but overproduction is a numbers game and it is fueled mostly by the marketing of the elite stallion farms as this University of Lincoln study points out. The fact is that the same percentage of thoroughbreds from annual crops arrive at the track as did in the 70’s and 80’s. Their times are the same and their stamina is depleted or at least appears to be. As pointed out, no distance is the standard, but probably 9f plus or minus is attractive to the U S industry thinking. The point I was trying to make was that there are no “entry barriers” to the market. Early retirement of graded winners is the norm and simply from a financial standpoint is the basis for the market. For the most part, the industry doesn’t take time to evaluate the full athletic potential of the colts it retains for stud. Two years of racing is hardly time to fully evaluate the distance potential or the athletic quality of a individual colt. The selection process is totally based on the accept and discard policy.

http://www.economicissues.org.uk/Files/2011/111dRodgers.pdf

Actually, imho, the UK and AUS offer the best research on TB breeding market. They are least honest about their industry. In a number of recent articles the Aussies are openly admitting to breeding for speed. The evidence is there for everyone to see.

By the way, snarky suits you. No need to explain your “this is a bit if not a lot of rubbish.” You are not the only one who has ever traveled overseas.

[Shammy_Davis]

Here is an interesting Aussie 2014 article that might be of interest to the OP. Have a feeling this link has long applied to U S breeding but we stay quiet about it.

http://m.phys.org/news/2014-10-genetic-jackpot-melbourne-cup-winner.html

[Shammy_Davis]

[QUOTE=vineyridge;8702119]
Here’s the point about milers–at least in the past. If anyone still believes in Hill’s Speed Gene (absent the insertion at or near the same point that seems to have been developed in horses from the Americas), a horse could be homozygous for the speed variant (CC), it could be homozygous for the stamina variant (TT) or it could be heterozygous (CT). IIRC, almost all English stallions from the past whose DNA was tested lacked the C variant, which seems to have been widely spread with the import of horses from North America. Now the C variant is present in the vast number of modern TBs.

Milers have been good stallions for over a hundred years. It has been postulated that perhaps part of their appeal could be that the vast majority are heterozygous for the speed gene, which determines in part how muscles are developed and function in the adult horse. If a CT stallion is bred to a mare with a C allele, the odds are that there is a 25% chance of a CC offspring. If bred to a mare carrying a T variant, there is at least a 25% chance of a TT offspring. So a stallion who is heterozygous for the gene would be able to produce offspring at each end of the speed spectrum. And since the mile is neither a real sprint or a real distance, it has been postulated that the heterozygous racer would have an advantage, since it carries both the propensity for speed and for stamina.

However, I will say that this theory is based on older science. There may be new studies out there that I am not aware of that show something completely different (other than the existence of the specific insertion that has been proved to affect speed and is found primarily in horses with a background in the Americas).[/QUOTE]

You may have seen this historical perspective but some may not have.

http://m.nautil.us/issue/10/mergers--acquisitions/can-science-breed-the-next-secretariat

[vineyridge]

Since that article was published, there has been another discovery–an indel located very close to Hill’s gene that is even more connected to speed in racing horses. It’s only been found in horses with ancestors from the Americas, and it’s present in almost all of the short track sprinters. Oddly enough, it was found by some Italian scientists.

Its discovery seems to show that when TBs were imported from North America and bred into the European TB, the whole breed changed. I still think that Croucher and Hunting Squirrel may have been how the indel entered the US population.