Estimation of Body Composition in Pregnant and Non-Pregnant Heifers

Abstract
Eigteen grade Hereford heifers (eight pregnant and 10 non-pregnant) were used to study relationships among carcass, offal and empty body composition. Relationships between carcass density, empty body weight, body composition and the effect of pregnancy upon these relationships were determined. Carcass density was highly correlated with percentage dry matter (-.96), percentage ether extract (-.97), percentage nitrogen (.94) and gross energy (Mcal/kg, -.97) in the carcass. High correlations were also observed between carcass density and percentage dry matter (-.96), percentage ether extract (-.97), percentage nitrogen (.89) and gross energy (Mcal/kg, -.97) in the empty body. Significant relationships were found between carcass weight and empty body weight and between percentages of dry matter, ether extract, ash or nitrogen or gross energy (Mcal/kg) in the carcass and empty body. Regressions between the weight or percentages of the gross chemical components in the offal and the respective components in the carcass or empty body had slightly lower coefficients of correlation than did the relationships between carcass density and carcass or empty body compositions or the relationships between carcass composition and empty body composition. Empty body weight, carcass composition or carcass density provided good indices of empty body composition. Pregnancy did not significantly alter any of these relationships. Copyright © 1976. American Society of Animal Science . Copyright 1976 by American Society of Animal Science.