PSVII-10 Effect of Lactobacillus spp. and Saccharomyces cerevisiae alone or in combination on the fermentation and aerobic stability of whole-crop corn silage

The objectives of the study were to evaluate the effects of Lactobacillus spp. and Saccharomyces cerevisiae alone or in combination as inoculants on the ensiling characteristics and aerobic stability of corn silage. Chopped and kernel processed whole-crop corn was treated with either distilled water (CON), or with (cfu g1 fresh forage) 1.1 × 105 of a Lactobacillus plantarum and Lactobacillus buchneri (LAB) mixture (INOC1), 1.0 × 104 S. cerevisiae strain 3 (INOC2), or 1.1 × 105 LAB + 1.0 × 104 S. cerevisiae strain 3 (INOC3) and ensiled in mini-silos. Minisilos were opened at 7, 30, 60 and 90 d of ensiling and a subsample of d 90 silage was used to assess stability after 3, 7, 14 and 21 d of aerobic exposure. Silages were analyzed for chemical and fermentation traits and enumerated for LAB, total bacteria, yeast and mold. Data were analyzed as repeated measures with treatment (T), days of ensiling or aerobic exposure (D) and T × D as main effects, and individual minisilos (n = 3) or insulated containers (n = 3) served as the experimental unit for ensiling and aerobic stability parameters, respectively. Silage in INOC2 had lower pH (P < 0.01), higher lactate (P = 0.03), lower acetate (P < 0.01) and lower LAB counts (P = 0.05) than INOC1 at d 90. Yeast in INOC2 tended to be higher (P = 0.08) than INOC3 on d 3 of aerobic exposure. Aerobic stability of INOC3 was greater (P = 0.01) than CON and INOC2. A combination of LAB and S. cerevisiae strain 3 did not impact fermentation, but enhanced the aerobic stability of corn silage. This raises the possibility of delivering S. cerevisiae strain 3 as direct fed microbial to ruminants in corn silage.