A comparison of 15 ram breeds for export lamb production 2. Proportions of export cuts and carcass class

摘要

The proportions of cuts from 7885 lamb carcasses sired by 15 different ram breeds, reared on pasture at two locations over 10 years, were measured and examined for breed differences. Although highly significant breed differences were found, their magnitude was small reaching a largest difference between crosses of 1.22% for the leg and 1.26% for the loin compared at the same carcass weight. Compared at the same time of slaughter (age), the maximum differences between the progeny of different ram breeds were 1.02% for the leg and 1.06% for the loin. Wether lambs had a slightly higher proportion of forequarter cuts. Sire breed had a major effect on the proportion of lambs reaching the fatter P grade (class) with the meat breeds Southdown, Dorset Down, South Dorset Down, Hampshire, and South Suffolk sires producing 68–76% P carcasses and the wool breeds such as the English Leicester, Merino, Romney, and Lincoln producing 18–23% of P carcasses. Lambs sired by the Poll Dorset, Dorset Horn, Suffolk, Ryeland, Border Leicester, and Cheviot produced 49–62% P carcasses.