The aim of this study was to evaluate the production costs and economic return of soybean husks (CS) associated with two non-protein nitrogen (NNP) sources, in feedlot finishing lamb. Eighty (80) Suffolk cross lambs, averaging initial age of 79 ± 6 days and initial live weight of 23.11 ± 1.78 kg were used. The animals were grouped in four experimental lots accordingly to NNP source: conventional urea group (CUG, n = 20), which received 1% of common urea; protected urea group (PUG, n = 20), which received 1% of protected urea, at the ratio of 1% + 0.5% conventional urea, of total diet, respectively; and control group, with no additional source of NNP. Total production cost (CT) of lambs at weaning was R$ 85.27/animal. In this cost ewes contributed with 68.55%, followed by the lamb cost (0-67 days), which represented 25.57% and rams with only 5.88%. The average CT in feedlot finishing was of R$ 57.73/lamb. Effective operational cost (COEf) represented R$ 57.35 or 99.33% of CT finishing. Variables of higher representativeness of COEf were: ration (61.56%) and taxes (31.06%). Diets with higher positive gross margin (MB)/lamb were GUC and CG (R$ 1.77 and R$ 44.35), respectively. All diets presented negative net margin (ML) and economic return (RE). In finishing systems of feedlot lamb, the use of diets with no additional source of non-protein nitrogen is the option that allows better economic and productivity results.
costs; economic response; sheep
