Is It Possible to Improve the Fermentation and Nutritional Quality of Wheat Straw Silage by Replacing Commercial Inoculant with Kefir?

Abstract

The current study aimed to determine fermentation quality, aerobic stability, and enzyme soluble organic matter (ELOS) of wheat straw silage by replacing homofermentative (it and homofermentative+heterofermentative (Hm+HT) lactic acid bacteria (LAB) inoculants with kefir as silage additives. For this purpose, commercially available Biota] Plus IT ((HM)LAB). Biota] Buchneri 500 ((HM+HT)LAB), and MYStarter KF (KF) were used as silage additives. Four kg of wheat straw, about 400 g/kg, and 6.0 log cfu of inoculants or kefir were used in each treatment group and replicate. Including the control group (CON), a total of 12 laboratory-type silos (3 replicates and 4 groups) were opened after 45 days. The dry matter (DM), crude ash (CA), acid detergent lignin (ADL), and water-soluble carbohydrate contents of silages were not affected by the addition of (HM)LAB, (HM+HT)LAB, and KF (P>0.05). The KF group had the lowest pH value (4.32), NH3N content (71.97 g/kg TN), and higher lactic acid content (43.11 g/kg DM). The crude protein (CP) ratio was decreased in (HM)LAB (5.95%) and (HM+HT)LAB (5.63%) groups and increased in the KF group (4.54%, P<0.001). An improvement (by lowering 17.02%) of NDF was only observed in the KF group (P<0.001). The ELOS and ME in (HM)LAB (HM+HT)LAB, and KF groups were increased (P<0.001). The lowest carbon dioxide (3.42 g/kg DM) and yeast (5.50 log10 cfu/g) were observed in the KF and CON group, respectively. According to research findings, kefir could be an alternative silage additive to commercially available inoculants and could improve wheat straw silage's nutritional quality instead of them.