Characteristics of carcass and non-carcass components of lambs fed wet brewery waste as a roughage feed

The objective of the present study was to evaluate the effect of including wet brewery waste (WBW) as the exclusive dietary roughage source on the characteristics of carcass and non-carcass components of feedlot-finished lambs. Thirty-two non-castrated male lambs weaned at 50 days of age, resulting from the cross between the Texel and Ile de France breeds, were used. The diet was constituted by roughage (WBW) and a concentrate composed of crushed maize, soybean meal, limestone and common salt. Treatments consisted of four levels of WBW as the roughage source in the diet (% dry matter), namely, 31, 44, 57 and 70%. Lambs were slaughtered upon reaching 34 kg live weight. The treatments resulted in a linear decrease in hot and cold carcass weights and yields, carcass compactness index, conformation, degree of fatness and rib-eye area. Among the primal cuts, the absolute weights of pallet, ribs and legs decreased as the WBW level was increased. As to the non-carcass components, only the total gastrointestinal content increased linearly with WBW. The increasing levels of WBW led to greater fasting losses and reduced carcass weights and yields. There was also a reduction in the degree of fatness, carcass compactness, carcass conformation index and rib-eye area Wet brewery waste at the concentration of 31% as the roughage source in the diet of finishing lambs in the feedlot provides better carcass traits.