Abstract #413

# 413
Altered rumen fermentation patterns in lactating dairy cows supplemented with phytochemicals improves milk production and efficiency.
R. C. B. Grazziontin1, J. Halfen*2,1, F. Rosa1, J. L. Anderson1, V. Ballard3, J. S. Osorio1, 1Dairy and Food Science Department,South Dakota State University, Brookings, SD, 2Núcleo de Pesquisa, Ensino e Extensão em Pecuária (NUPEEC), Departamento de Clínica Veterinaria, Universidade Federal de Pelotas, Pelotas, RS, Brazil, 3Groupe CCPA, Janzé, France.

Tannins and other phytochemicals can improve RUP in the diet by binding protein and then limiting ruminal degradation, which can improve milk yield and milk protein synthesis. The objective of this study was to evaluate the effects of dietary phytochemicals (tannins and Capsicum annum) as rumen modifiers on production parameters and milk efficiency in dairy cows. Twenty-four multiparous Holstein cows (96 ± 16 DIM; mean ± SD) were used in a 3 × 3 Latin Square design with a covariate period. Cows were blocked according to DIM, milk production, and BW and randomly assigned to a treatment sequence (n = 8/group). The experiment consisted of a 14-d covariate period and three 30-d treatment periods. Cows received a basal diet supplemented with soybean meal pellets (SB) as the control diet, phytochemicals (RUM; Rumiviv, CCPA, Janzé, France) pelleted with soybean meal, or expellers soybean meal (ESBM; SoyPlus, Ralston, IA). Milk production and DMI during the last 4 d of each period were used for statistical analysis. Blood and rumen fluid samples were collected on d 27 of each period. Rumen fluid was analyzed for ammonia N and VFA as well as ruminal bacteria via qPCR amplification of 16s rDNA genes. Data were analyzed using the MIXED procedure of SAS. Greater (P < 0.03) milk yield (37.9 vs 36 kg/d), ECM (39.7 vs 37.1 kg/d), and protein yield (1.15 vs 1.08 kg/d) were observed in RUM than SB, but RUM and ESBM were similar. Total VFA (118.1 vs 101.5 mM), as well as propionate (28.6 vs 24.5 mM) and butyrate (10.8 vs 9.4 mM) concentration, were greater (P ≤ 0.04) in RUM in comparison to SB and ESBM diets. Cows fed RUM had greater (P ≤ 0.05) BHB (0.49 vs 0.42 mmol/L) than SB and ESBM. Streptococcus bovis in rumen fluid was lower (P ≤ 0.01) in RUM than SB and ESBM diets, and a trend (P ≤ 0.09) for lower Selenomonas ruminatium and Succinimonas amylolytica was observed in RUM than SB and ESBM. Overall, data suggest that feeding a mixture of phytochemicals can significantly affect rumen microbiota and fermentation patterns and these were reflected in better milk production and efficiency.

Key Words: phytochemicals, rumen-undegradable protein, microbiota