The Effects of Live Yeast Culture (Saccharomyces cerevisiae) on Rumen Fermentation and Nutrient Degradability in Yearling Lambs

Summary This study was carried out in two experiments. Experiment 1 was conducted with six ruminally-cannulated one-year old Kangal Akkaraman male lambs, using a crossover design with 2 periods to determine the effects of live yeast culture supplementation on rumen fermentation. Yearlings were either supplemented with 4 g/d of Saccharomyces cerevisiae (BeneSacc, 4x10 9 CFU/g) or not supplemented (control). Animals were penned individually, and were fed a diet composed of 25% forage and 75% concentrate for sixteen days. Rumen fluid was sampled on day 16, 0 h (before feeding), 3 h and 6 h after feeding. Rumen pH, the numbers of protozoa, ammonia-N and volatile fatty acids (VFA) were determined in samples. Molar proportions of acetate were decreased, and propionate was increased with supplementation of live yeast culture. No differences were observed for ruminal pH, protozoa population, total VFA and ammonia-N concentrations, between treatments. In Experiment 2, in situ nutrient degradability of barley grain, corn dried distillers grains with solubles (DDGS) and wheat straw were determined. Live yeast culture supplementation did not affect dry matter (DM) degradability of barley, DDGS or straw, crude protein (CP) degradability of DDGS, nor neutral detergent fiber (NDF) degradability of straw. But, it reduced the potential degradability of DDGS in rumen..