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This study was carried out to determine the effect of lactic acid bacteria+enzyme (LAB+E) mixture inoculants on the fermentation, aerobic stability, and in vitro organic matter digestibility (IVOMD) of wet brewers grain silages. SILAID (Global Nutritech Biotechnology LLC, Richmond, VA) containing water soluble Lactobacillus plantarum and Enterococcus faecium bacteria with cellulase, pentosanaz and amylase was used as bacterial inoculants. Inoculants were applied to silages at 5x105, 1x106 and 5x106 cfu/g levels. Wet brewers grains were ensiled in 1.0 litter special jars equipped with a lid that enabled gas release only. Silages were sampled for chemical and microbiological analyses on day 60 after ensiling and subjected to aerobic stability test for 5 days. In addition, IVOMD of silage was determined with enzymatic technique. Lactic acid bacteria+enzyme mixture inoculants decreased the pH, ammonia nitrogen and acetic acid whereas increased the lactic acid and lactobacilli count of silages (P<0.05). In addition, LAB+E mixture inoculants decreased neutral detergent fiber, acid detergent fiber and cellulose contents (P<0.05) whereas were not effect IVOMD of silages (P>0.05). [ABSTRACT FROM AUTHOR]

Simple Summary: Minimizing silage additives cost while increasing silage quality is important for a sustainable livestock enterprise, especially in undeveloped and developing countries. In this study, therefore, commercially available kefir yeast (CK) and homemade kefir culture (HK), as a low-cost additive, was applied at untreated a common control (CON) and three different application doses (5.0, 5.7, and 6.0 log cfu g−1) on wilted alfalfa and evaluated with the fermentation characteristics and aerobic stability. The addition of HK with an application dose greater than 5.0 log cfu g−1 prevents mold formation and inhibits yeast counts in silages. Indeed, both CK and HK improve the silage quality and aerobic stability of alfalfa even with low water-soluble carbohydrate content. The present study has been one of the first attempts to thoroughly examine the effects of different kefir sources on fermentation characteristics, aerobic stability, and microbial communities of alfalfa silages. The effects of commercial kefir (CK) and homemade kefir culture (HK) applied with untreated a common control (CON) and three different application doses (5.0, 5.7, and 6.0 log cfu g−1) on wilted alfalfa and stored at an ambient temperature of 25–30 °C are studied. After 45 days of ensiling, fermentation characteristics and aerobic stability of silages were measured, and bacterial diversity was investigated by 16S ribosomal RNA gene sequencing using the GenomeLab™ GeXP platform. Both CK and HK accelerate more lactic acid production and reduced ammonia nitrogen concentration. Factor analysis of kefir sources suggests that the addition of kefir improves the aerobic stability of silages, even the initial water-soluble carbohydrate (WSC) content is inadequate via its antimicrobial effect on yeast and mold formation. Enterococcus faecium, Pediococcus pentosaceous and Lactobacillus brevis were dominant bacterial species among the treated groups at silo opening, while Lactobacillus plantarum and Lactobacillus brevis became dominant bacterial species after 7 days of aerobic exposure. In conclusion, the application of kefir on alfalfa silages improves fermentation quality and aerobic stability even with low WSC content. [ABSTRACT FROM AUTHOR]