Fiber degradability, chemical composition and conservation characteristics of alfalfa haylage ensiled with exogenous fibrolytic enzymes and a ferulic acid esterase-producing inoculant

This study investigated the effects of two fibrolytic enzyme products, applied at baling alone or in combination with a ferulic acid esterase-producing bacterial additive, on the ensilage dynamics, chemical composition and digestibility of alfalfa haylage. Five replicate wrapped bales were produced with one of five treatments, including an untreated control, and one of two fibrolytic enzyme products (EN1 and EN2) applied either alone or in combination with a ferulic-acid producing bacterial additive (FAEI). No effect of treatment was observed on the neutral detergent fiber (NDF) (P = 0.889) or acid detergent fiber (ADF) (P = 0.065) concentrations of haylage after ensilage, but haylage produced using fibrolytic enzyme products underwent greater (P < 0.018) increases in temperature following exposure to aerobic conditions. Haylages produced with fibrolytic enzyme products had a greater (P < 0.001) in vitro NDF degradability (NDFD) than untreated haylage. The use of fibrolytic enzymes applied to alfalfa haylage at ensiling increased the NDFD, despite minimal effects on the chemical composition of the herbage. However, the greater aerobic deterioration of fibrolytic enzyme-treated bales indicates higher dry matter losses during aerobic exposure. The use of FAEI with fibrolytic enzymes did not further enhance the effects of fibrolytic-enzyme treatments.