Effects of a commercial inoculant of lactic acid bacteria on the composition of silages made from grasses of low dry matter content

Abstract

Abstract The efficacy of a commercial inoculant, Natuferm, which contains multiple strains of lactic acid bacteria, was examined in seven experiments using 6 m 3 pilot‐scale silos. Samples taken during the fermentation period were analysed and compared with samples from untreated controls and formic acid silages. Good quality silages were obtained with crops of low dry matter content (12–14%) and with a water soluble carbohydrate content of 1·5% related to fresh weight. The addition of Natuferm resulted in increased lactic acid levels (50–90%) during the initial fermentation, and pH dropped faster compared with the untreated controls. Compared with the formic acid silages the level of enterobacteria declined rapidly in both the inoculated and untreated silages. In two of the experiments a pronounced difference in enterobacterial count was observed between the Natuferm and control silages on day 2. The effluent volumes were recorded, and the pH and the dry matter content of the effluent were determined. Compared with the formic acid silages, a 40% average reduction of the effluent flow was observed from Natuferm silages, and in most experiments there was also a reduced effluent volume compared with the controls. Analyses of 174 Natuferm silages and 73 formic acid silages from full scale (farm) silos revealed no significant differences in silage quality between the two additives. Natuferm silages with a dry matter content below 20% were not significantly different from silages with a dry matter content above 20%.