The objective of this study was to evaluate the influence of four substitution levels (0; 33; 67 and 100%) of soybean meal by detoxified castor cake on performance and carcass characteristics of 20 non-castrated male crossbred Morada Nova lambs, with mean body weight of 18.7 kg, in a randomized blocks design with four treatments and five replicates. Performance, carcass weight, carcass yield and relative composition of the commercial cuts were evaluated. The substitution levels of soybean meal by detoxified castor cake had no effect on final live weight or total weight gain in feedlot, but it caused decreasing linear effect on average daily gain and feed conversion ratio was observed. There was no effect of the substitution levels of soybean meal by detoxified castor cake on final body weight, live weight at fasting, empty body weight, hot carcass weight or cold carcass weight. The hot carcass yield was affected by substitution levels; the same behavior was observed for cold carcass yield. Rib weight and yield and shoulders yield had linear decrease of substitution levels of soybean meal by detoxified castor cake, whereas weight and yield of other regions did not present any effect for the substitution levels. Detoxified castor cake can be utilized in levels of up to 67% in substitution of the soybean meal in sheep diets.
biodiesel byproducts; carcass yield; lambs; Ricinus communis
