EFFECTS OF NUTRITIONAL RESTRICTION ON THE PERFORMANCE IN FEEDLOT YOUNG BULLS

The objective of the study was to evaluate compensatory weight gain in the performance of young bulls submitted to feed restriction, in the initial phase of confinement and to study the economic viability of th e utilization of three protein sources. Sixty six crossbred bulls Sime ntal-Nelore, eight months old and averaging 220 kg of weight were subm itted to three feeding programs in the growth phase that lasted 84 day s. The feeding programs were ad libitum, restriction + raw soybean gra ins and restriction + toasted soybean grains, with a restriction level of 25% on average. In the finishing phase, with a 61 day duration, an imals fed with each of the three diets mentioned above received two ty pes of supplementary diets: raw soybean grains and poultry litter. The re were no differences between final weights of animals in finishing p hase, but the bulls submitted to the restriction had more weight gain per day and better food conversion than ad libitum animals, for both r aw soybean grains and poultry litter. The conclusion was that the feed ing restriction and consequent compensatory weight gain, presented adv antages for feeding efficiency, by decreasing maintenance requirements , although final cost had been equivalent to ad libitum animals.