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Demystifying Dosage


By Roger Lyons

        "All we're trying to do is find out what you're best at," was the standard explanation for that barrage of "aptitude tests" so familiar to little Jane and little Johnny, who attended American schools in the 1950s and 60s. The explanation given to little Heather and little Zachary i the 1970s and 80s probably didn't differ much. The names--of the children and the tests-- were changed, but that didn't protect the innocent. These tests had a hidden agenda, which can be illustrated thus.
        Suppose little Johnny's percentile scores were 85 in English, 92 in Math, 78 in spatial relationships, and 83 in logical analysis. Now, it is clear from this that little Johnny was best in Math. But the same thing is clear from the following scores, which were earned by little Jane: 32 in English, 45 in Math, 39 in spatial relationships, and 28 in logical analysis. Even though little Jane and little Johnny both showed their highest aptitudes in Math, the difference in the scale of their scores suggests another criterion of assessment that was probably a more important variable in the lives of Jane and Johnny than the question of aptitude.

        The variable we are looking for is competence. There is really no other word for it, whether the term is referred to humans or horses. Competence is about doing something well in either case.
        Many breeders believe that dosage is like an aptitude test, that it measures both what a horse will be best at and, then, how well the horse will perform in that capacity relative to other horses. They believe that a dosage index of less than 4.00 and a center of distribution below 1.25 means that the sire and dam are a good match, that the productive possibilities of the mare are somehow optimized if she is bred to a stallion who puts the dosage right. Moreover, breeders who hold this belief do so without understanding how dosage accomplishes this. They believe that the dosage figures comprise a mysterious code that ordinary intelligence simply cannot fathom.
        Many new entrants into the business of breeding thoroughbreds spend time trying to find out the secret to decoding the dosage figures, having been led to believe that these figures hold the key to breeding good racehorses. The simplistic nature of the figures beckon to them, enticing them to find the key, the hidden meaning. They assume that this meaning eludes them because they lack the knowledge to comprehend it.
        In fact, the dosage figures differ from an aptitude test in the respect that nothing about about them constitutes a measure of what can correctly be called competence in the racehorse. Dosage figures may predict that a horse will run his best race at 10 furlongs, but, even if that turns out to be the case, it doesn't mean he will ever win a race.
        The dosage figures really are as simple as they seem. They do not reveal more than they seem to reveal. Their pertinence to the question of competence is elusive for the simple reason that it does not exist.

        Prior to Roman's entrance into the dosage game, it was generally understood that the superior thoroughbred is an athlete, constituting a fortunate mixture of speed, stamina, soundness, courage, and the will to win. Largely as a result of Roman's formulations, breeders have been led to believe that a superior thoroughbred is a blend of speed and stamina only. After all, the dosage formulations are exclusively regulated by these two aptitudes. Unfortunately, a balance of these two factors alone, as represented by the Kentucky Derby guidelines, is a poor balance indeed since it ignores other, equally important values.
        There is a parallel in the experience of little Johnny and little Jane. Because she had certain aptitudes that the tests forgot to measure, she became an entrepreneur in the fashion industry and earned $900,000 a year. Little Johnny went on to college, became even more competent within his range of aptitudes, and ended up with a career as a social services professional. After 20 years of that, he happily retired on his state pension, compliments of the tax revenues yielded by grown-up Jane's creativity, resourcefulness, and enterprising spirit.
        But even if the dosage figures took into account all of the important aptitudes, which they don't do, how much better off would a breeder be to breed a horse with a dosage index of way above 4.0 and a center of distribution that is off the scale, if only the horse had the courage and the stoutness and the will--all heritable characteristics--to win the Breeders' Cup Sprint? Ironically, by the logic of the dosage figures themselves, if a horse doesn't have dosage figures something like that, then he can't possibly win that race. How can one explain why Texas and Oklahoma breeders--or California breeders, for that matter--would want a dosage index below 4.0?
        For any breeder, Roman's dosage is a red herring, in whatever direction it might be chased (with the exception of the betting window on Derby day). Breeders must attend to and learn about the aptitudinal capacities of the individual ancestors that influence a mare and make selections from among stallions whose ancestries complement that of the mare. Which stallions that might be is discovered by examining the ancestries of sires of superior runners produced by mares of similar ancestry to that of the mare in question. The dosage figures do not even presume to approximate that painstaking process.

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