PSVII-3 Effects of Feeding Direct-fed Microbials on Digestibility and Rumen Fermentation Characteristics of Finishing Bos Indicus Cattle

Abstract Direct feed microbials (DFM) are probiotics often fed to feedlot cattle offered improve rumen fermentation and/or intestinal health, thus benefiting animal health and performance. We hypothesized that DFM supplementation would nutrient digestibility in finishing Bos indicus cattle. On day -1, 30 rumen-cannulated Nellore bulls were blocked based on initial body weight (BW; 350 ± 35.0 kg) 1 of pens and, within each block, animals randomly assigned to: (1) Control: corn-based diet without (n = 10), (2) EFSC: CONT + gram/head per a Enterococcus faecium Saccharomyces cerevisiae (Probios Precise, Chr. Hansen A/S, Horsholm, Denmark; n (3) BLBS: 2 grams/head Bacillus licheniformis subtilis (Bovacillus, A/S; 10). The experimental period lasted 35 days, while between days 33, total fecal collection was performed 34 35, feces fluid collected at 0, 3, 6, 9, 12, 15, 18, 21 h post-feeding for ammonia, VFA, pH determination. All data analyzed as orthogonal contrasts using SAS: vs. EFSC BLBS. Inclusion or type did not affect either ruminal parameters (P ≥ 0.40). In contrast, supplementation, regardless type, yielded reduced mean ammonia concentration (14.7 15.7 mg/L; P 0.05). Moreover, concentrations decreased 3 6 ≤ 0.04), but also less BSBL < 0.01). summary, proteolysis, with no effect other diet.