There are few linear measurements available for feet and legs, and heritability of those measurements (usefulness to predict mating results) is quite low. In each generation of new heifers you find you still get cows who cannot walk smoothly, who have trouble getting into or out of free stalls, who go chronically lame or at least require constant hoof trimming—in spite of fifty years of selection pressure through “Foot and Leg composites” and other indexed measurements.
There has to be a better way. And in fact, there is, once you learn to apply the concepts of physical balance to your matings. Focus on “function” rather than breed to the “average” of any trait measurement. Recognize the ways in which index selection leads to extreme physical results, and utilize individual matings to counteract that tendency.
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