Avaliação nutricional e caracterização da lignina da Brachiaria brizantha em dois sistemas silvipastoris

• Ano de defesa: 2006
• Autor(a) principal: Guilherme Rocha Moreira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; Brasil; Programa de Pós-Graduação em Zootecnia; UFMG
• Palavras-chave em Português: Forragem; Lignina; Nutrição animal
• Link de acesso: http://hdl.handle.net/1843/31915

The study was conducted in two silvopastoral systems (SSP’s) located in Brazilian Savannah, Lagoa Santa city, Minas Gerais state, Brazil and began on the agricultural year of 2004-2005. The aim of this study was to evaluate the influencee of SSP’s composed by Zeyheria tuberculosa and Myracrodruon urundeuva over this parameter: chemical composition, concentration lignin, fenolic monomers of lignin: p-hidroxyhenyl (H), vanillin (V), sirinyl (S), relation V/S and in situ degradability of the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) Brachiaria brizantha cv. Marandu forage. Chemical composition was based on randomized block design, composed of five blocks (cutting period), two treatments for each arboreal (shaded an full sun) and three repetitions per treatment. In situ, design was in split-plot, so that treatments were the plot, times of incubation were split-plot and animals were blocked. Compararison among treatments was made between an arboreal and control (Z. tuberculosa x area with full sun and M. urundeuva x area with full sun). Shade provided by the arboreal Z. tuberculosa and M. urundeuva reduced (P<0,05) concentration of the DM of the studied forage and enlarged (P<0,05) CP concentration. There was not influence (P>0,05) of the shade provided by arboreal Z. tuberculosa on the concentration of NDF in Brachiaria brizantha cv. Marandu, however the concentration of ADF was affected (P<0,05) when compared to the control (area with full sun). The concentration of NDF and ADF didn’t vary (P>0,05) comparing the shaded forage with the arboreal M. urundeuva and its control (area with full sun). Lignin concentration was 30% and 6,3% larger in the shaded forage by arboreal Z. tuberculosa and M. urundeuva when compared to its controls. Fenolic monomers of lignin in B. brizantha cv. Marandu shaded by the arboreal Z. tuberculosa presented larger concentrations of H, S and lower values of V and relation of V/S groups when compared to the control. Forage shaded by arboreal M. urundeuva presented larger concentrations of V and S, however lower concentrations of H and relation of V/S when compared to the control. In relation to in situ degradability, results demonstrated that forage shaded by Z. tuberculosa presented larger (P<0,05) degradability of CP, however there was no effect (P>0,05) of shade on DM, NDF and ADF degradability when compared to the respective control. Shaded provided by M. urundeuva did not affect (P>0,05) DM, CP, NDF and ADF degradability of B. brizantha cv. Marandu when compared to control.