Microbial Inoculation or Cellulase Enzyme Treatment of Barley and Vetch Silage Harvested at Three Maturities

Abstract

A mixture of barley and hairy vetch was harvested at the following three maturities for barley and vetch, respectively; early boot-prebloom (early), early heading-midbloom (middle), and soft dough-seeding (late). At each maturity, measurements were made of forage yield and nutrient composition. Forage was cut and wilted prior to ensiling in laboratory silos corresponding to the following treatments: 1) control silage; 2) microbial inoculant (added to 1 × 105 cfu/g of wet forage); or 3) cellulase enzyme complex (.5% of wet weight). Yield of total forage DM increased from 5741 to 19,379kg/ha from early to late harvest, respectively. Forage decreased in N and water-soluble carbohydrate content with increasing maturity but ADF, NDF, and ADL content increased with maturity. Differences in forage composition were greater between early and middle maturities than between middle and late maturities. Microbial inoculation reduced silage pH, acetate, and NH3 N but increased lactic acid concentration when averaged across all maturities. Addition of cellulase enzyme reduced silage pH but did not affect acid or fiber concentrations. In vitro DM digestion was significantly reduced by stage of maturity but not by inoculation or cellulase treatment. A mixture of barley and vetch resulted in substantial forage yields with moderately high levels of N. Microbial inoculation, but not cellulase treatment improved the fermentation characteristics of silage.