Horse running through field

Pedigree, Conformation, and Zenyatta

by Roger Lyons

My last post explains why a recent post by Frank Mitchell gave me second thoughts about the appropriateness of Giant’s Causeway as a mate for Zenyatta in spite of the sterling statistical profile he has with her ancestry. My underlying point is that what’s on paper can and must be interpreted in light of what’s on the ground–and vice versa. That point drew some thoughtful comments bearing substantively on the case and more generally on the relation between pedigree and conformation.

First, Frank elaborates his reasons for thinking Giant’s Causeway might not be quite right for her, and it has a lot to do with her broodmare sire, Kris S. Frank not only casts his gaze on a lot of horses, but he also measures them, so you can be sure that he’s not speaking from casual observation. When he casts his gaze on Zenyatta, he sees a lot of Kris S. and some Troy, the broodmare sire of her sire, Street Cry.

Then Michele shares the experience, as a breeder, of having tried both approaches–breeding largely on pedigree and, alternatively, breeding largely on conformation, concluding that neither approach seems to make much difference in the frequency of favorable outcomes. Michele’s experiment was not conducted in a lab. It unfolded at much cost and over many years of trying to breed the best horses possible, and, as you read the comment, you get the sense that it rings true.

In the last comment so far, Greg correctly concludes that the distinction between pedigree and conformation is nothing more than a matter of emphasis. After all, he explains, statistical analyses that assess how a given stallion has done with mares representing a given ancestor actually do capture conformation issues–although indirectly. If you read Frank’s “The Weekender Pedigree” (and who doesn’t?) at The Paulick Report, then you know how much he’s into pedigree even though his science is biomechanics. The opposition routinely invoked by the cliche “pedigree vs. conformation” exists only because we associate pedigree analysis with one broad category of facts and conformation with another.

Greg proposes marriage of the two approaches, and he’s right. When Frank says that Kris S. is the major player in Zenyatta’s conformation (note the implication that pedigree and conformation are inseparable), it relieves a lot of statistical pressure. Rather than assuming Zenyatta’s entire ancestry to be more or less uniformly relevant, the focus can shift to Kris S.

Here are the candidates, along with their numbers with mares representing Kris S.: A.P. Indy (2/6), Galileo (1/2 and Frank’s choice), Giant’s Causeway (3/10), Invincible Spirit (1/2), Lemon Drop Kid (1/3), Mineshaft (2/5), Oasis Dream (0/2 with Kris S., but 7/35 with Roberto and great supporting numbers), Speightstown (0/2 with Kris S., but 2/10 with Roberto and good supporting numbers). And, by the way, Songandaprayer is 2/4 with Kris S. and may be a better choice for Zenyatta than better stallions that have poor or questionable numbers with Kris S.