The experiment was conducted in Região Central do Rio Grande do Sul, in order to evaluate the performance of the steers in elefantegrass (Pennisetum purpureum Schum.), under continuous grazing associed with different sources supplementation: 0.3; 0.7; 1.1 and 1.5% of live weight day-1 (LW). Thirty two Charolais (C), Nellore (N), 5/8 CN e 5/8 NC steers calves with na average age of one hundred twenty day, with average live weight of 98.5kg. The supplementation period was 84 days, divided in four periods of the 21 days. The forage mass of the pasture of elefantegrass presented average values of dry matter 20.44% (DM), crude protein 10.67% (CP) e 7.006.0kg de DM ha-1 during experimental period. The proportion of green leaf matter was of 22.62% representation an green leaf dry total of 1.650.8kg de DM ha-1. No significant interaction was observed between sources supplementation and evaluation period for average weight gain (ADG). Observed what the ADG was of 0.365 kg, no obtained significant difference between the sources, with ADG of 0.279, 0.380, 0.338 e 0.466kg day-1 for 0.3, 0.7, 1.1 e 1.5% do LW, respectively. In the analysis of the periods of supplementation, the GMD was bigger (P<.05) in the third period (0.545kg day-1) and minor (P<.05) in the fourth period (0.145kg day-1) comparatively to the first (0.342kg day-1) and to the second (0.431kg day-1) periods.
stocking rate; forage available; weight gain; summer pasture
