EFFECTS OF BREED AND SEX ON THE RELATIVE GROWTH AND DISTRIBUTION OF BONE IN CATTLE

Abstract

The relative growth and distribution of bone from 256 bovine carcasses were compared among three breed-types (British, up to 30% Charolais and 30–50% Charolais) and three "sexes" (heifers, steers and bulls) over a wide range in carcass weight. The growth pattern for each bone relative to total side bone was estimated from the growth coefficient, b, in the allometric equation (Y = aXb). Growth coefficients were homogeneous among both breed-types and sexes for each bone relative to total side bone, indicating that different breeds and sexes followed similar patterns of relative bone growth as they increased in size. The lowest growth coefficients in the carcass were found in the neck and limb bones all of which had growth coefficients significantly less than 1.0. The thoracic and lumbar vertebrae and the sternum had growth coefficients not significantly different from 1.0 and the ribs, pelvic and pectoral girdles had growth coefficients significantly greater than 1.0. Significant breed-type and "sex" differences were found in the weights of individual bones when adjusted to equal side bone weight. However, these were small and probably reflected differences in stage of maturity.