Impact of ferulic acid esterase-producing lactobacilli and fibrolytic enzymes on ensiling and digestion kinetics of mixed small-grain silage.

This study evaluated the effects of a ferulic acid esterase ( FAE) and a non- FAE-producing inoculant applied alone or in combination with exogenous fibrolytic enzymes ( EFE) on the fermentation and nutritive value of mixed grain (barley, oats and spring triticale) silage. The mixed crop was ensiled in laboratory mini-silos either untreated ( CON), or treated with a FAE inoculant ( FAE), a non- FAE inoculant ( NFAE) or NFAE + EFE. Inoculated silages were lower ( P < 0·01) in water-soluble carbohydrate, whereas NFAE and NFAE + EFE silages had higher ( P < 0·001) DM loss than other silages. FAE and NFAE silage had higher neutral detergent fibre ( NDF), but were lower in NFAE + EFE than other silages ( P < 0·001). Copy numbers of 16S rRNA associated with Lactobacillus buchneri were higher ( P < 0·001) in NFAE and NFAE + EFE silages than in others, resulting in higher ( P < 0·001) acetic acid in these silages. NFAE + EFE silage had lower ( P < 0·001) in vitro gas production and NDF digestibility ( NDFD) than other silages. FAE silage had higher ( P < 0·01) in situ NDFD than CON and NFAE + EFE silages. Inoculation of mixed small-grain silage with NFAE-producing inoculants combining EFE reduced NDFD. [ABSTRACT FROM AUTHOR]