Effects of lactic acid bacteria inoculants and cellulase on fermentation quality and in vitro digestibility of Leymus chinensis silage

The objective of this experiment was to investigate the silage quality and in vitro degradation of Leymus chinensis treated with different additives. The treatments were lactic acid bacteria inoculants (LB), lignocellulose degradation enzymes (E), a mixture of the two additives (LB+E) or no additive treatment as control. Forages were separately ensiled for 1, 3, 5, 15 and 45days and three replications were opened at each sampling time. Silages treated with additives (i.e. LB, E and LB+E) were characterized by lower pH value, higher lactic acid content and lower levels of acetic acid, butyric acid, ammonia-N and water soluble carbohydrate throughout the ensiling period compared with the control (P<0.05). Silages treated by LB+E had the lowest pH value and highest lactic acid concentration among the four treatments (P<0.05). The levels of neutral detergent fiber (after heat stable amylase treatment, aNDF), acid detergent fiber (ADF) and non-protein nitrogen were lower in additive treated silages than in the control silage (P<0.05). The LB treatment improved in vitro digestibility of dry matter and protein, while the E treatment improved in vitro aNDF digestibility compared with untreated silage. In comparison with the E treated silage, silage treated with LB+E had higher levels of ADF and acid detergent lignin concentrations (P<0.05). These results indicated that the application of lactic acid bacteria combined with cellulase could be an efficient strategy to improve both fermentation quality and in vitro digestibility of the wild grass silage of L.chinensis.