Enzymes as silage additive. Effect on fermentation quality, digestibility in sheep, degradability in sacco and performance in growing cattle

Authors

• Pekka Huhtanen Department of Animal Husbandry, University of Helsinki, SF-00710 HELSINKI, Finland
• Kari Hissa Department of Animal Husbandry, University of Helsinki, SF-00710 HELSINKI, Finland
• Seija Jaakkola Department of Animal Husbandry, University of Helsinki, SF-00710 HELSINKI, Finland

DOI: https://doi.org/10.23986/afsci.72205

Abstract

Fungal glucose oxidase and cellulase were used as silage additives in laboratory (25 l), pilot (3 m3) and farm scale (250 t) silos. In 3 m3 scale silos, pH and the concentration of acetic acid were lower and the concentrations of lactic acid and sugars were higher in the enzyme treated than in untreated silage. The concentration of butyric acid was equal to or lower than in formic acid treated silage in all experiments. Cell wall constituents were degraded in the silo by cellulase and thus more energy was available for lactic acid bacteria. With increasing levels of cellulase application, the disappearance of organic matter (OM) from nylon bags incubated for 1 to 12 h in the rumen of a dairy cow increased significantly (P<0.001, P<0.01) in two different experiments. The level of cellulase had no effect on the ratio N/OM disappeared from nylon bags. Digestibilities of OM in sheep were 75.8, 76.5 and 77.2 % for untreated, formic acid and enzyme treated silage (P>0.05). On untreated silage diet N retention tended to be reduced in sheep compared with formic acid or enzyme treated silages. In growing bulls there were no differences in feed intake, growth rate, feed conversion rate, carcass characteristics or OM digestibility between formic acid (41/t) and enzyme treated silage.