Outcross, Hybrid Vigor and the Derby: A question for Louis

[Pan Zareta]

xfactor wrote:

. . . The modern Thoroughbred is not a hybrid.. .

Excellent point. The TB has been bred for 250 years in a closed stud book. Any breeder who placed any attention on the ability of a TB mating to throw "vigor" has long been pushing up flowers.

It's perhaps more accurate to refer to the TB as a composite breed, "hybrid" usually being defined as the offspring of two genetically dissimilar parents. "Hybrid vigor" = a phenotype perceived as superior in those offspring and regarded as attributable to the genetic dissimilarity of the parents. Hybrid vigor is the goal, but not always the outcome, of "outcrossing". The real trick is to maintain hybrid vigor, i.e. stabilize type in succeeding generations. Especially in a closed population, this tends to be a'hit-or-miss' endeavor when genetic dissimilarity is estimated from phenotype alone. Phenotype can be deceptive, to say the least. Better to know the genotype. This is where the SNP chips have the potential to be quite helpful.

[diomed]

Xfactor

enjoyed your post and agree that mules, not warmblood/coldblood crosses are hybrids

However, we, or at least the industry, does produce "hybrid" corn not by crossing it with millet, or perhaps a more related grain, but by inbreeding selective strains of corn and then doing F1 and F2 outcrosses.

Maybe there is some validity to the notion that you get something similar to the seed corn industry calls "hybrid-vigor" when you out-cross two strains of unrelated inbred horses. Might be interesting to be able to do an F2 out-cross with TBs and observe the result.

This probably has little to do with TBs but many years ago we purchased a "Rag Apple" bull out of Canada who produced superior milk producers out of everything he covered.. he was so good we bred him back to his own daughters who were superior to their grandmothers but not their mothers. However, these in-bred daughter/grand daughters produced better than them selves when out-crossed to our next unrelated bull.

Need to point out the "next unrelated bull" was not inbred so his offspring were nothing even close to an F2 cross.

Again, I am talking about milk production not how fast these cows could run.

griff

Round Oak Rag Apple Elevation? I remember him well. The most fantastic producer of type(show ring build) ever. Was this a son of his or himself? Elevation was the most celebrated Holstien bull of all time. I bred my champion cow to a son of his(Straight Pine Elevation Pete) but she didn't take. It was a $75 ampule of semen. It bummed me out that I never got a calf from this mating.
I grew up Dairy farming and we bred artificially and showed many fine cows at the local and state level. Seeing somebody bring up "Rag Apple" brings back so many memories.

[Shammy Davis]

PZ wrote:

It's perhaps more accurate to refer to the TB as a composite breed, "hybrid" usually being defined as the offspring of two genetically dissimilar parents. "Hybrid vigor" = a phenotype perceived as superior in those offspring and regarded as attributable to the genetic dissimilarity of the parents. Hybrid vigor is the goal,. . .

The studbook has been closed for 250 years plus or minus, if you count errors and multiple names in the late 18th, early 19th century. Despite, Louis, IMHO hybrid vigor is not an issue any longer. Phenotypes and genotypes are probably as fixed as they are ever going to be. There are comparable comparisons between the TB of the 1800's and the present day breed. I cringe to think that anyone would realistically believe that any attention would be paid to hybrid vigor in this day and age when we speak of the TB. The back of the dust jacket of Binns & Morris' "Thoroughbred Breeding" there is a picture of VOLTIGEUR, the 1850 Derby and St Leger winner. If a horse, past or present, could ever be a picture perfect TB racehorse, VOLTIGEUR is certainly that.

The Arabian Horse is considered a purebred. Are we really sure? Does it matter? The Arabian horse has been around for thousands of years. Does anyone think in terms of hyrbid vigor related to an outcross within Arabian lines. No.

My point, of course, considering the hundreds of years that have past, is let's not get to concerned about hybrid or composite this or that. If ever the studbook is opened, then we might be have something to talk about. Until then, we have the genome project and again IMO that's is where the real discussion lies.

To be perfectly honest, even with forty plus years of breeding hunting retreivers I wouldn't know hybrid vigor if it smacked me in the face. I always seemed to get what I was looking for based on an evaluation of the dog and bitch.

I hate vague terms like unsoundness and vigor.

[Pan Zareta]

I hate vague terms like unsoundness and vigor.

I do too. Apparently, I didn't get that point across very well.

[Shammy Davis]

PZ: On this genetic stuff, I've always got to defer to you, xfactor, diomed, et al. I can't wait for the day when equine genome project has it all figured out and all we've got to do is plug in the sire and dame and voila! Kentucky Derby winner!

SNP chips? Refresh my beseiged memory, please.

You know this thread started out as question for Louis. We taking a big chance posting. We could be accused of "bullying."

[Pan Zareta]

PZ: On this genetic stuff, I've always got to defer to you, xfactor, diomed, et al. I can't wait for the day when equine genome project has it all figured out and all we've got to do is plug in the sire and dame and voila! Kentucky Derby winner!

SNP chips? Refresh my beseiged memory, please.

You know this thread started out as question for Louis. We taking a big chance posting. We could be accused of "bullying."

I think we're still well within the scope of the OP.

SNP = single nucleotide polymorphism. Like the change from a T to a C at a single nucleotide position on equine chromosome 18 that can significantly alter expression of the myostatin gene. A SNP chip is a small piece of silicon(?) carrying probes that, when exposed to DNA, checks for SNPs at tens or hundreds of thousands of nucleotide positions across the genome.

[Shammy Davis]

PZ: Ahhhhh! Thanks.

[vineyridge]

One rather interesting thing to me about Tesio is that he used Catnip, whose dam was North American and she worked REALLY well for him. He also used, IIRC, Orby--whose dam was North American--through Grand Parade (Derby winner) in the mare Navarra. The previous is wrong. He used Grand Parade several times: once with Nera di Bicci, a Catnip daughter, for Nella da Gubbio, once with Giottina for Gherada del Notte, and once with Fausta for Magnasco. Both of his Grand Parade mares were excellent racers, and both ended up in Germany
.
I've come to believe that there was enough variation from the British TB in the North American founding population that use of US mares would have been the equivalent of outcrossing in other breeds. This began to happen in the 1890's and very early 20th century with the export of whole stables during the racing blackout. I've found Aethelstan and Durbar in France, Graf Ferry in Germany, Orby and Lady Josephine in the UK, and the Tesio breds. And when the stables were returned to the US, they brought back many new lines, which helped prepare the way for Nearco's and Lady Josephine's success here.

About Tesio: http://users.libero.it/riccardobassani/tesioexhibit.htm
Who knew?

[Shammy Davis]

Vineyridge posted:

One rather interesting thing to me about Tesio is that he used Catnip, whose dam was North American and she worked REALLY well for him. He also used, IIRC, Orby whose dam was North American in the mare Navarra.

I've come to believe that there was enough variation from the British TB in the North American founding population that use of US mares would have been the equivalent of outcrossing in other breeds. This began to happen in the 1890's and very early 20th century with the export of whole stables during the racing blackout. I've found Aethelstan and Durbar in France, Graf Ferry in Germany, Orby and Lady Josephine in the UK, and the Tesio breds. And when the stables were returned to the US, they brought back many new lines, which helped prepare the way for Nearco's and Lady Josephine's success here.

I hate to say this, but I'm intimidated by your (xfactor, PZ, Diomed, et al) posts. You have such a great depth of knowledge about early pedigrees and more specifically individual horses of those bygone eras. When you post would it be possible for you provide a link or resource that we could use to play catch up on the individual topic or pedigrees. I've been reading Binns & Morris' TB Breeding and I'm amazed at how the pedigree and its information was accumulated for horses in the late 18th and early 19th century. I could really enjoy this discussion and the history behind it if my memory was better (now I can't find the tractor key) and I had a reference or link to help me. Best wishes.

[vineyridge]

I hate to say this, but I'm intimidated by your (xfactor, PZ, Diomed, et al) posts. You have such a great depth of knowledge about early pedigrees and more specifically individual horses of those bygone eras. When you post would it be possible for you provide a link or resource that we could use to play catch up on the individual topic or pedigrees. I've been reading Binns & Morris' TB Breeding and I'm amazed at how the pedigree and its information was accumulated for horses in the late 18th and early 19th century. I could really enjoy this discussion and the history behind it if my memory was better (now I can't find the tractor key) and I had a reference or link to help me. Best wishes.

What sort of help do you need? If I can, I'll link to the source.

[Shammy Davis]

Are you posting to individual horses that you have researched or are you sources in book or other forms? Me thinks this is your personal research and without something to reference, it is impossible for me to follow by just looking at a pedigree, breeder info, or dates.

Links? Resources?

[vineyridge]

Are you posting to individual horses that you have researched or are you sources in book or other forms? Me thinks this is your personal research and without something to reference, it is impossible for me to follow by just looking at a pedigree, breeder info, or dates.

Links? Resources?

Online Personal research.

TB Heritage, of course, and Bloodlines.net, both of which are invaluable resources on the start of the breed. All of the pedigree databases that I can access. Other old books on TB history that I can find online--mostly in google books. There are quite a few and some are free for reading. The early history of the North American TB has been researched extensively; and then sometimes I just get online and noodle to find information.

It's a hobby, and I have the kind of memory that is somewhat similar to a database and a brain to analyze and synthesize.

PZ is the expert.

I've just found out that the EPR is not complete. This is distressing.

[Shammy Davis]

I'll just have to ask a great many questions. EPR?

[vineyridge]

European Produce Records. Brisnet publication from JC data that is supposed to have European mares and their foals from 1950 to, in my case, 2007. I was looking up some of the German horses with North American mares in their pedigrees here, went to the JC and they weren't there, went to the EPR and they weren't there, then went to Parlo's database, Galopp Seiger, and found them. They raced in Germany and either won or placed in high class races. Even found a chaser mare who raced up to 4600 meters. She was a winner and placer.

Galopp Seiger is a wonderful database and has the actual race records for the horses, as does France Galop.

[Pan Zareta]

I've just found out that the EPR is not complete.

Far from it! The EPRs err heavily toward near relatives of Euro-breds that made an appearance on the turf or in the stud in NorthAm. The early APRs on CD are way more complete than any of the EPRs but even those frequently omit horses foaled before ~1940 that didn't have any reg. TB progeny or produce. And for the mares whose produce is recorded therein, the identity of their sires and/or dams who were foaled before ~1900 are often given as "unknown".

Warts and all, the stud books are by far the better source for info re. pedigree and produce/progeny.

Shammy, for further info regarding the Tesio-breds there is always Tesio's own Breeding The Racehorse. First printed in the 1950's, numerous copies are available on the secondary market at quite reasonable price.