Silicato no rendimento, composição química e degradabilidade no campim-marundu

Abstract

The objective of this research was to evaluate the chemical composition and digestibility of Marandu grass subjected to different doses and sources of silicon. The experiment was carried out at experimental farm of UNIMONTES, campus Janaúba-MG. The experiment was in randomized blocks in a factorial scheme 4 x 2 + 1, composed of 4 levels of calcium silicate (400 kg ha-1, 800 kg ha-1, 1600 kg ha-1, 2400 kg ha-1, two sources of calcium silicate (Agrossilício and Silmag) and a control (magnesium limestone). The yield of fresh matter (NMR) and dry matter production (DMP) were evaluated. We determined the MM, CP, NDIN, NIDA, NDF, ADF, NDF/ADF ratio, lignin, cellulose, hemicellulose and in situ digestibility of DM and NDF and their respective rumen parameters. Silicates were higher (p <0.05) to control for all variables of the chemical composition except for lignin (p> 0.05). Addition of increasing doses of agrossilício reduce the content of DM, DMP, MM, NMR, CP, lignin; and increasing doses of Silmag decrease DMP, NDF / ADF, the content of MM , NM, hemicellulose and lignin. The agrossilício showed quadract effect for cellulose, hemicellulose, NDF/ADF, NDF, ADF, and NDIN ADIN. The Silmag had the same behavior for DM, CP, cellulose, NDF, ADF, and NDIN ADIN. The disappearance and digestibility of DM and NDF of the forage were not affected by treatments. Meanwhile, Silmag showed 2.58 % and 0.01 % of fractions ED and C of DM, respectively, more than the agrossilício. Only Silmag in dosage of 400 kg ha-1 exceeded the control. Nevertheless, Silmag showed 3.31 %, 3.45 % and 3.95 % of ED at doses of 400, 800 and 1600 kg ha-1 more than the agrossilício, respectively. The agrossilício at the dosage of 400 kg ha-1 results in better responses in terms of yield, chemical composition and digestibility in Marandu grass.