This trial was carried out to evaluate performance, carcass traits and non-carcass components of lambs fed with a conventional diet plus other three diets with crescent levels of urea in substitution of a true protein source. 48 crossbred male lambs (Ile de France x Corriedale) weaned at 70 days of age were used. They grew and were finished in feedlot randomly allocated in four groups according to urea levels (0.0; 0.4; 0.8 and 1.2% of total dry matter). Animals were slaughtered with 32kg of live weight. There was no difference among urea levels for the following parameters: daily weight gain, live weight at slaughter, hot and chilled carcass weights, percentage of weight losses during chilling, commercial and biological carcass dressing out, non-carcass components weights, body condition and conformation, and fat deposition. However, for the skin weight (kg) the 0.0% level was lower than the 0.8% level. There were not observed differences among treatments for the following variables: muscle pH at three moments, morphometric and carcass cut proportions. The leg length of the lambs fed diet with 0.8% urea was lower than that of 0.0% level. For leg compacity, 0.8% was smaller than the leg length of those fed with 0.o% urea. It was concluded that growing levels of urea utilization is viable and did not affect the variables that were analyzed in this work.
sheep; alimentation; performance; meat
