Published online by Cambridge University Press: 02 September 2010
The effects of average carcass fat concentration of a group of lambs on correlations among lamb carcass measurements within the group and of slaughter age on variances of carcass measurements were studied. Three-hundred and sixty-eight crossbred lambs from one experiment were slaughtered on 10 days over a 2-year period. Average carcass fat concentration of the 10 groups ranged from 179 to 326 g/kg carcass weight. Variances of carcass fat, water and protein concentrations and of muscle measurements did not increase at later slaughter ages but variances of kidney fat weight, fat depths and total tissue depths increased. Several correlations among carcass measurements had significant regressions on average carcass fat composition of the groups slaughtered. When measurements were adjusted for age but not weight, correlations of carcass weight, kidney fat weight, specific gravity, tibia and tarsus length and m. longissimus depth with carcass fat, water and protein concentrations weakened as carcass fat concentration of the group increased. Correlations of kidney fat, specific gravity and m. longissimus width with fat, water and protein concentrations adjusted for carcass weight weakened as average carcass fat concentration of the group increased. Multiple regression equations did not reveal any advantage in using combinations of muscle or leg dimensions to predict fat concentration.