Características fermentativas e composição bromatológica da silagem de cultivares de milheto com inclusão de casca de soja

Abstract

The chemical composition, fermentation characteristics and the carbohydrates and protein fractionation from three pearl millet cultivars silages with soybean hulls inclusion were evaluated. The treatments consisted in three pearl millet cultivars: ADR 8010, ADR 500 and BRS 1501 and four soybean hulls inclusion levels: 0%, 3%, 6% and 10%. Average pearl millet silages dry matter levels differed according to soybean hulls inclusion levels; ranging from 17.03% to 22.96% function to soybean hulls inclusion levels 0% and 10%, respectively. Crude protein levels ranged from 9.46% to 10.79% and significant differences in crude protein were observed among pearl millet cultivars. The contents of neutral detergent fiber (NDF) and acid detergent fiber (ADF) did not differ in response to soybean hulls inclusion; average NDF ranged from 53.51% (BRS 1501) to 56.78% (ADR 8010); average FDA contents ranged from 28.88% (BRS 1501) to 31.79% (ADR 8010). The hemicellulose, cellulose, lignin and mineral matter contents differ depending on soybean hulls levels; they increased to the extent that increased the soybean hulls levels. The highest soybean hulls inclusion level (10%) resulted in lowest losses due to gases and effluents. The pH values found in this study ranged from 4.07 to 4.85. The average buffering capacity values ranged from 10.82 mEq NaOH/100g DM (ADR 8010) to 30.19 mEqNaOH/100g DM (ADR 8010), for the inclusion levels 6% and 0%, respectively. The average concentration of ammonia nitrogen (NH3-N/TN) remained below 8%. Mean soluble carbohydrates levels differ (P<0.05) function both to soybean hulls inclusion levels and to cultivar evaluated; ranging from 5.17% (ADR 500) in the control treatment up to 9.73% (BRS 1501) with 10% soybean hulls addition. The lactic acid contents were significantly influenced (P<0.05) by soybean hulls inclusion levels, ranging from 5.07% (ADR 8010) added with 10% soybean hulls to 7.10% (BRS 1501) in the control treatment. The average levels of acetic, propionic and butyric acids ranged from 1.22% to 1.52%; 0.12% to 0.14% and 0.03% to 0.04%, respectively, and did not differ significantly. Total carbohydrates content (TC) differed (P<0.05), function both to soybean hulls inclusion levels and to pearl millet cultivars; varying from 78.84% (ADR 8010) to 82.12% (ADR 500). The average values from fraction “A+B1” ranged from 28.52% to 34.43%; not differing significantly (P>0.05) among soybean hulls levels. Fraction “B2” and fraction “C” contents differed significantly (P<0.05) function to treatments, ranging from 53.99% (BRS 1501) to 66.41% (ADR 8010) and 5.07% to 11.20%, respectively. Regarding to protein; fraction “A”, fractions “B1+B2”, fractions “B3 and fraction “C”, levels differed significantly (P<0.05) function to soybean hulls inclusion, ranging from 30.85% to 44.27%, 15.48% to 43.29%, 25.4% to 39.78% and 0.40% to 0.84%, respectively. The pearl millet cultivars fermentation characteristics and chemical composition allow us to classify them as good quality silages. The soybean hulls, was efficient as adsorbent additive.