Productive performance and nutritional characteristics of crossbreds Nellore young bulls, in the growing stage, receiving different supplement offers, from July to September 2006, grazing on Brachiaria decumbens pasture were evaluated. The area was divided in five paddocks of 2.0 ha, with availability of dry matter and potentially digestible dry matter of 3.88 and 2.22 t/ha, respectively. Thirty animals of 230.0 ± 6.14 kg initial weight and 8.5 ± 0.18 months of age were assigned in a completely randomized experimental design with five treatments, and four supplementation levels. Mineral mix (60 g/day) and multiple supplements, formulated to supply different supplementation levels in the amounts of 0.5, 1.0, 1.5 and 2.0 kg/animal to supply 300 g/day of crude protein were evaluated. Animals responded to the use of multiples supplements, gaining more weight (88.72%), in addition to showing higher seric N-urea levels (19.95 vs. 9.66), when compared with animals fed diets supplied with mineral mix. Animals under supplementation showed higher intake of DM, OM, EE, NDF, NFC and TDN in relation to animals without supplementation, and this intake increased with the levels of supplement offer. Supplementation increased the coefficient of digestion of the majority of variables, regardless of the supplementation level. More moderate levels (0.5 kg) of multiple supplement may be provided to young bulls in the growing stage, during the dry season, to stimulate intake of pasture; however the maximum microbial yield is achieved with 1.34 kg of supplement. The best responses of performance and nutritional characteristics can be obtained with dairy supply of supplement in levels of 0.5 to 1.34 kg/animal.
beef cattle; daily gain; digestibility; intake; pasture
