Effect of adding lactic acid bacteria and molasses on fermentation quality and in vitro ruminal digestion of total mixed ration silage prepared with whole crop rice

This study examined the effects of molasses (M) and lactic acid bacteria (LAB) on the quality of total mixed ration (TMR) silages prepared with whole crop rice (WCR) and tofu cake (TC). Chemical composition, organic acids, and in vitro ruminal digestion were determined. Silages were prepared using a small-scale system of silage fermentation. Treatments included control silage without additive, or with M (4% fresh matter basis), LAB (5 mg kg-1 fresh mater basis, Lactobacillus plantarum Chikuso-1), and M+LAB. After 60 days of fermentation, there were no notable differences in chemical composition among treatments. The four silages were of good quality with low pH and NH3-N, and high lactic acid (LA) and V-scores. Both LAB and M+LAB silages had more (P = 0.005) LA contents than the control and M silages. Addition of LAB tended to decrease (P = 0.065) ruminal methane production after 6 h in vitro incubation, although DM digestibility, total volatile fatty acids, and the molar concentrations of acetic acid, isovaleric acid, valeric acid, propionic acid, and the acetic : propionic acid ratio were not affected, whereas butyric acid was higher (P = 0.008) with the control than with the other silages. Our results suggest that adding LAB increased the LA content of TMR silage and tended to decrease ruminal methane production, while adding M did not significantly increase the LA content of TMR silage and tended to increase ruminal methane production in vitro.