The effects of bacterial inoculants on the fermentation, aerobic stability and rumen degradability characteristics of wheat silages

Abstract

This study was carried out to determine the effects of lactic acid bacteria (LAB) inoculants on the fermentation, aerobic stability and in situ rumen degradability characteristics of wheat silages. Wheat was harvested at the early dough stage. Inoculant-1188 (Pioneer (R), USA) and Sil-All (Alltech, UK) were used as LAB inoculants. Inoculants were applied to silages at 1.5 x 10(6) cfu/g levels. Wheat material was ensiled in 1.5-l special anaerobic jars, equipped with a lid enabling gas release only. Three jars from each group were sampled for chemical and microbiological analysis 2, 4, 8, 15 and 50 days after ensiling. At the end of the ensiling period all silages were subjected to an aerobic stability test for 5 days. In addition, in situ rumen degradability characteristics were determined in the silages. Both homofermentative LAB inoculants improved the fermentation characteristics of wheat silages. At the end of the ensiling period inoculants increased the lactobacilli and decreased yeast and mold numbers of the silages. However, both LAB inoculants led to higher CO2 production and impaired the aerobic stability of the silages. The in situ degradability characteristics of the wheat silages were not affected by the inoculant treatment.