Chemical Changes during Ensilage and In sacco Degradation of Two Tropical Grasses: Rhodesgrass and Guineagrass Treated with Cell Wall-degrading Enzymes

Effects of the cell wall-degrading enzymes derived from Acremonium cellulolyticus and Trichoderma viride on the silage fermentation and in sacco degradation of tropical grasses i.e. rhodesgrass (Chloris gayana Kunth. cv. Callide) and guineagrass (Panicum maximum Jacq. cv. Natsukaze) were investigated in laboratory-scale experiments. These two grasses were either treated with or without the enzymes before ensiling. Untreated rhodesgrass produced acetate fermentation silage (lactate, DM; acetate, DM) with high final pH value and -N content (5.84 and DM). Addition of enzymes significantly increased (p DM) and decreased (p-N (4.80 and DM) in the ensiled forages when compared with the control silages. Untreated guineagrass was successfully preserved with a high lactate proportion (lactate, 45.5; acetate, DM), and the addition of enzymes further enhanced the desirable fermentation (lactate, DM; acetate, DM). The content of NDF was lowered (p DM; guineagrass, DM). Changes in the kinetics of in sacco degradation showed that enzyme treatment increased (p DM; guineagrass, 324 vs. DM) but did not influence the potential degradation, lag time and degradation rate of DM and NDF in the two silages.