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The aim of this study was to evaluate the performance of lambs Santa Ines breed supplemented with different food sources in the scrubland conditions in the Brazilian semiarid. The experimental design was a complete randomized block with four treatments and six replications totaling twenty-four non-emasculated males, with an initial mean body weight of 19.9 kg + 3.12 kg. These animals were grazing in the scrubland until achieve mean body weight of 30 kg. The food supplementation was based on corn, soybean and mineral mixture in the proportion: (MM) (123.8 g of Ca/kg, 68 g of P/kg, 12 g of S/kg, 600 ppm of Cu, 100 ppm of Co, 368 ppm of Fe, 120 ppm of I and 12 ppm of Se, 600 ppm of Mn and 600 ppm of Zn). Treatments were: T1/NaCl (200 g/day of energetic-protein with NaCl); T2/CMM (200 g/day of energetic-protein-mineral); T3/CMM (300 g/day of energetic-protein-mineral) and T4/SMn (300 g/day of energetic-protein-mineral without Mn). Animal response was evaluated every 15 days, Liveweights were obtained following an overnight period without water and feed.  The paddock occupation was limited in function of the grazing pressure, without allowing forage availability inferior to 60% in proportion to the forage availability at the begging of the study. Analysis of variance (P>0.05) were performed on the data. The animals fed with the diets T3 and T4 presented performed better than the animals on T1 and T2, probably due to the poor quality nutritional condition of forage. There was no difference between T1 and T2; this suggests that the addition of a mix mineral in the diet of labs of the Santa Ines breed raised under extensive system conditions in the semiarid Brazilian is not recommended when the supplementation concentration is lower than 200g/da.