title: Hoof overgrowth in Holstein--Friesian dairy cattle.
abstract: The genetic etiology of hoof overgrowth, a widespread problem in Holstein-Friesian cattle, was examined. Although all four feet are affected, the hind feet usually have a greater degree of overgrowth. There is a distinct age tendency for the trait; the younger cows' hooves grow faster than those of the older cows, but the overgrowth in older cows reaches greater proportions. Analysis of variance of chi-square frequency tests showed that there is a component of heritability involved in the expression of the trait, but that it follows a more complex model than a simple autosomal recessive gene would show.
mesh_terms: D000367:Age Factors; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000235:genetics*; D005260:Female; D006724:Hoof and Claw / Q000002:abnormalities*; D008297:Male