Desempenho de bovinos em pastos de capim-braquiária suplementados nos períodos de água e seca

• Autor(a) principal: Santos, Anselmo de Deus
• Data de Publicação: 2012
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1821
• topic: Brachiaria decumbes; Pastagem; Manejo; Diferimento; Desempenho animal; Brachiaria decumbes; Grassland; Management; Deferral; Animal performance; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::PASTAGEM E FORRAGICULTURA::AVALIACAO, PRODUCAO E CONSERVACAO DE FORRAGENS

The purpose of this study was to evaluate the effect of concentrated supplementation (0, 1, 2, and 3 kg/animal day) in the rainy and dry periods (deferred pastures) on the structural characteristics, the morphological composition, the nutritional value of the produced forage, and the cattle performance in pastures of Brachiaria decumbens cv. Basilisk (signal grass) managed in continuous stocking. In experiment 1 (rainy), from January to April in 2011, the pastures were managed in continuous stocking and variable stocking rate, with the objective of maintaining the height at 20 cm. The supplement doses were evaluated in a complete randomized block design, with two replications. In experiment 2 (dry), from July to October in 2011, the pastures were deferred in April and used from July on. In this occasion, the pastures returned to be grazed by cattle in continuous stocking and fixed initial stocking rate of 2.2 UA/ha. Throughout the utilization of the pastures, the supplement doses of the pasture were evaluated in a complete randomized block design, with two replications. In experiment 1, the concentrated supplement did not influence the mass and the accumulation of forage and morphologic components. The densities of vegetative, dead, live, aerial and defoliated tillers, the content of crude protein, the digestibility in vitro of the organic matter, and the fiber in neutral detergent were not affected by the level of concentrated supplementation either. In experiment 2, the heights of the pasture and of the extended plant decreased linearly with the increase in the grazing period. The masses of total forage and of live stem decreased linearly with the grazing period. The mass of the live leaf lamina was influenced in a quadratic relation by the supplement doses and the grazing period. The content of crude protein and the digestibility in vitro of the organic matter were not influenced by the grazing period, presenting in average, 8.1 and 52.7%, respectively. The gain of the average daily weight, the stocking rate, and the yield per area increased linearly with the elevation in the supplement dose. Even without the supplement utilization, the cattle presented daily weight gain of 0.441 kg/animal day, average stocking rate of 2.76 UA/ha, and average yield per are of 2.74 kg/ha day. The concentrated supplementation in pastures of signal grass, managed at 20 cm during the rainy period, or deferred and used, during the dry period, increases the animal performance.