FEEDLOT PERFORMANCE OF FIVE BREEDS OF SHEEP AND THEIR CARCASS CHARACTERISTICS
Average daily gains of Suffolk, Targhee, Columbia, Rambouillet, and Romnelet wether lambs in three 75-day tests were: 0.20, 0.18, 0.16, 0.15, and 0.13 kg. The average carcass weights were: Suffolk, 26.0; Targhee, 23.0; Columbia, 21.5; Rambouillet, 21.7; and Romnelet, 20.9 kg. Only Columbias graded lower (P < 0.01) in carcass score than Suffolks. Single lambs had significantly (P < 0.01) higher carcass grades than twins. Preweaning environmental variables such as age of dam, type of rearing, and creep feeding on range did not affect postweaning gain in the feedlot.Breed differences were small in carcass measurements and weights of wholesale cuts as determined on constant weight basis. The most typical conformation characteristics of the Suffolk carcass, in relation to the other breeds, were: shorter body and hind leg, shallower chest, wider hips, and larger circumference of hind leg. Carcass weight was the most important source of variation in the carcass measurements and weights of wholesale cuts.Breed differences in tenderness, muscle fiber thickness, and amount of fat deposited throughout the muscle were small.