Produ??o de leite em pastagens de Capim-Massai em sistemas agrossilvipastoris

• Ano de defesa: 2021
• Autor(a) principal: Silva, Aline Barros da
• Orientador(a): Carvalho, Carlos Augusto Brand?o de
• Banca de defesa: Carvalho, Carlos Augusto Brand?o de, Barros, In?cio de, M?ller, Marcelo Dias, Paiva, Adenilson Jos?, Moura, Andr? Morais
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal Rural do Rio de Janeiro
• Programa de Pós-Graduação: Programa de P?s-Gradua??o em Ci?ncia Animal
• Departamento: Instituto de Zootecnia
• País: Brasil
• Palavras-chave em Português: Conforto t?rmico; Megathyrsus maximus; Sistema de sombreamento moderado
• Palavras-chave em Inglês: Moderate shading system; Thermal comfort
• Área do conhecimento CNPq: Zootecnia
• Link de acesso: https://tede.ufrrj.br/jspui/handle/jspui/5743

An improved animal husbandry environment generates great benefits in the production results, obtained within dairy farming in Brazilian tropical regions. The aim was to evaluate the productive and qualitative performance of massai grass, the performance animal behavior of crossbred cows subjected to shade regimes with eucalyptus and in monoculture (full sun system-FSS; moderate shade system-MSS and intensive shade system-ISS). The experiment was carried out at Embrapa Agrossilvipastoril (Sinop, Mato Grosso state, Brazil) from 01/06/2018 to 06/14/2019. Structural characteristics, grazing losses, forage utilization and offers, nutritive value forage of massai grass, microclimate, stocking rates, animal behavior, individual production and milk quality were evaluated. The data under univariate statistics by SAS? On Demand and PDIFF (p<0.10) and multivariate (discriminant and principal component analysis) analyses were performed. The photosynthetic active radiation (PAR) was higher in the FSS, with a difference of 25% for the MSS and 50% for ISS. The average values of temperature and humidity indexes (THI) were higher than 72 in the three systems. The pre-grazing forage mass, dry mass of leaf blade and dry mass stem in MSS were intermediate to other systems (6,885; 3,206; and 2,105 kg ha-1 DM, respectively). The bulk density and utilization forage values were also intermediate in MSS (109.1 ha-1 cm-1 DM and 2,999 kg ha-1 DM, on average) compared to other systems. Higher crude protein contents were obtained in ISS (13.6%), intermediate in MSS (11.3%) and lower in SFS (10.1%). In summer/2017, individual milk production was higher in ISS than in the FSS, both similar to that in MSS (15.5 kg cow-1 day-1 of milk). In the rainy season, cows in shaded systems sought shade more frequently (66.5% on average) than those in SFS (15.9%), while in the dry period, the frequency was intermediate in MSS (59.7%), with a higher value for ISS (73.2%). Under conditions of low PAR, the steams of massai grass were less thick and lighter in the shaded systems, which can be attributed to pasture management by 95% light interception. The microclimate affected positively the productive performance of the Massai grass in full sun environment, however it affected negatively the crude protein content. In the MSS, there was greater productivity of grass-Massai in relation to the ISS, concomitant to the higher crude protein content of the forage than in the FSS. Milk production was very dependent on dry mass production, which is often favored in grass monoculture systems. Milk production was highly dependent on dry matter production, which is often favored in monoculture of this grass systems. Moderate shading promotes a balance between production and nutritional value of the Massai grass as well as ambience for dairy cows in the seasons of the year in northern Mato Grosso-Brazil.