Saturday, December 26, 2009

Thoughts on pedigree: Recency trumps 'ancient' history

A discussion in which I arrived late over at a Yahoo group I frequent -- that is, tb_breeding_theory -- finally piqued my interest this holiday weekend.

What is our obsession -- and by "our," I mean some pedigree enthusiasts -- with far-distant relatives in a horse's lineage?

My thoughts are prompted by a discussion about Nasrullah, which broadened to include other sires, including Hermit, and their influences on the breed, particularly negative traits including the perpetuation of bleeders, "roarers" (a breathing malady) and general unsoundness.

I find "deep-pedigree" research to be intriguing. In fact, I am pleased to know that my mare, Bushes Victory, is from the female line that produced both Seabiscuit and Equipoise. (All descend from British-born reine de course Ballantrae, born 1899.) But though that knowledge is quite interesting to me, it's virtually insignificant in determining whether "Tory" will produce good runners herself, no matter to whom she is mated.

To put it more directly, in my opinion the biggest factor in producing a successful racehorse is to ask of the lines being crossed, "What have you done for racing lately?"

An unraced mare from a family of modest to poor siblings, coupled with a marginal sire, is likely to produce a marginal racehorse, at best. It matters not that the foal is a great-great-grandson of Storm Cat out of a granddaughter of Mr. Prospector, or that he carries eight lines to a prepotent sire like Princequillo.

I suppose it's the same philosophy as the well-known husbandry adage: "Breed the best to the best and hope for the best."

In the Yahoo-group discussion, British turf journalist and author Tony Morris took up for Hermit, who another member noted had been criticized by author Richard Ulbrich as a "provable source of vascular weakness in the modern TB."

"Hermit was champion sire seven times," Morris wrote. "I don't think that would have happened if he habitually passed on his bleeding problem. I don't dispute the idea that the problem has been noted in some of his descendants, but I have to believe that Hermit is in every pedigree, generally many times over. It's not worth thinking about now."

And, almost unequivocally, I agree.

Certainly the traits of any living example are the product of his ancestors. But trying to attribute a specific flaw in today's horse to a stallion born 145 years ago is like playing pin-the-tail-on-the-donkey, in the dark, in the Louisiana Superdome.

Granted, the more lines to a certain ancestor that a modern-day descendant carries, the more likely it is that the current animal's identifiable traits, good or bad, can be attributed to the heavily represented ancestor who displayed the same. But each additional line contributes to that likelihood in tiny increments. And it would be foolish to consider oneself certain in pinning a 21st century flaw on a 19th century sire, particularly when it's so much easier and far more direct to just look at the horse's most recent ancestors.

As I wrote in my concurrence with Mr. Morris -- a supporting statement with which I suspect he's wholly unimpressed: "If the sire, dam and their sires and dams were not notorious bleeders, or roarers, or unsound, then it's likely the foal will not be, either, regardless how many lines of Hermit (or whatever other ancestor) that foal might be carrying. And if he is a bleeder, roarer or unsound, you could blame the flaw on anything or nothing with equal accuracy."

Indeed it is interesting -- and some experts are paid quite well -- to dig deep into pedigrees, touting mares as being from the female family of La Troienne, or carrying X-number of crosses to Hyperion. But the further-off that blood becomes, the less likely it is to bear any real significance on the prospective foal.

I do believe in the process of inbreeding as a means of enriching for qualities the breeder wants to see in a foal. (Be careful, for inbreeding also enriches for the negative traits that ancestor might have possessed.) But if that inbreeding doesn't take place in the first four, or five -- at most six or seven generations, and in that case heavily, perhaps with a half-dozen or more crosses -- I believe that the influence of that repeated ancestor on the current foal is more wishful thinking than reliable husbandry.

1 comment:

  1. I agree, Glenn, even though I'm like the Tinhorn who sings:
    And just a minute, boys,
    I've got the feedbox noise,
    It says his great-grandfather was Equipoise.


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