The objective of this work was to evaluate the influence of including legumes (clover) and the application of nitrogen on oat forage structural composition and production and the animal production in crop-live stocking integration system. It was used a random block experimental design with three replications. The factors were arranged in split-plots, so the plots were composed of evaluation periods and the split-plots were composed of the combination of clover with nitrogen fertilization(200 kg of N/ha using urea). The pasture method was the contiuous one, with variable stocking rate to keep forage height at 15 cm. It was used Purunã breed non-castrated young beef bulls at 10 months of age, with an initial average weight of 200 kg. The forrage mass avarage production was 2,378.96, 3,289.49, and 2,749.86 kg/ha for the control pastures, with clover and nitrogen, respectively, from July 12th to October 8th 2006, totalizing 89 days of grazing with an average forrage supply of 14.90 kg DM/100 kg body weight and daily weight gain of 1.280 kg /animal/day. At the end of the experiment, pasture beared a transportation capacity of 1,528.25; 1,244.32 and 1,156.17 kg of body weight for nitrogen fertilization, with clover and control, respectively. The highest animal/ha production was obtained with nitrogen fertilization (541.49 kg/ha). The inclusion of white clover intercropped with oats in system of crop-livestock integration is not enough to maintain the sustainability of intensive systems high productivity.
