Características agronômicas e desempenho de vacas em lactação em pastagem de grama estrela africana sob doses de nitrogênio

• Ano de defesa: 2015
• Autor(a) principal: Gomes, Lidiany Lopes
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Mestrado em Ciências Veterinárias; Centro de Ciências Agrárias e Engenharias; UFES; Programa de Pós-Graduação em Ciências Veterinárias
• Palavras-chave em Português: Adubação nitrogenada; Cynodon nlemfuensis; Produção de leite; Medicina Veterinária; 619
• Link de acesso: http://repositorio.ufes.br/handle/10/7775

This research was carried out in order to evaluate forage mass, its chemical composition and intake, cows live weight gain, body weight score, animal stocking and milk yield per cow and per area on an stargrass pasture under increasing nitrogen doses, in two seasons. Treatments were 0, 200, 400 e 600 kg/ha/year using urea as nitrogen source. A randomized block design with two replications was used and data were analyzed by mixed models using repeated measures in time (two seasons: from July to September and from September to November, 2013). Lactating Holstein x Zebu cows were blocked by milk production, lactation number, liveweight and by genetic group, using six cows per hectare in the start of the experiment. Beyond pasture dairy cows were fed with 2 kg/cow of a concentrate with 20% Crude Protein (CP) and 70% Total Digestible Nutrients (TDN) and 25 kg/cow/day of sorghum silage, during the experiment. Results showed that nitrogen fertilization exerts positive effect on productive characteristics of the African stargrass pasture and its morphological composition and increases on CP and IVDMD contents with increasing nitrogen doses, but with similar NDF contents. Dry matter intake was better in the fertilized pasture. Daily milk yield per cow was not affected by nitrogen doses applied in the pasture, but there are augments on animal stocking and milk yield per hectare and major values were observed in the pastures that received 400 and 600 kg/ha/year of nitrogen.