Two levels of protein and mineral supplements (290 and 400 g.an.-1.day-1) were evaluated and compared with the mineral supplement in 90 Nelore steers on star grass pasture (Cynodon plectostachyus Pilger) during the winter. The supplement intake was ajusted by the concentration of sodium clore into the mixture. Considering the first 28 days (adaptation period) in the statistical analysis, there was no difference in average daily gain (ADG). Taking out this period of adaptation, the ADG was better for the protein and mineral supplement with intake of 400 g.an.-1.day-1 (0.15 kg per animal a day), when compared with the other supplements (0.06 and 0.05 kg per animal a day, respectively for intake of 290 g.an.-1.day-1 of protein mineral supplements and mineral salt). The forage quality and availability were similar for the different treatments, with average levels of 4366 kg dry matter.ha-1, 2145 kg green dry matter.ha-1, and 353 kg of leaves.ha-1. The proportion of leaves and stems were reduced and the dead material proportion rose during the experimental periods. The chemical composition of forage had values of 3.5% of CP, 1.6% of digestible CP, 48.1% of ADF, and 48.4% of IVDMD. The sta grass pasture presented poor nutritional quality during beetwen the months of may and october, so the protein supplement is necessary to the animals mantain or gain weight during this period.
beef steers; crude protein; cynodon; stargrass; urea; winter season
