%0 Journal Article %9 journal article %J Journal of Animal and Feed Sciences %@ 1230-1388 %V 28 %N 3 %D 2019 %F Cherdthong2019 %T Effect of post-fermentative yeast biomass as a substitute for soybean meal on feed utilization and rumen ecology in Thai native beef cattle %X The aim of this experiment was to study the influence of substituting soybean meal (SBM) with post-fermentative yeast biomass (post-FYeB) powder on feed intake, ruminal fermentation, and bacteria and protozoa content in rumen fluid in beef cattle. The study was conducted on four male Thai native beef cattle at around 1 to 2 years of age with an initial body weight (BW) of 120 ± 20 kg. The experimental design was a 4 × 4 Latin square design and the dietary treatments included four levels of SBM substitution with post-FYeB in concentrate feed: 0, 33, 67 and 100%. The used post-FYeB contained 26.4% crude protein. Increasing levels of post-FYeB in concentrate diets did not alter roughage intake and total intake ( P > 0.05). Rice straw intake ranged from 2.0 to 2.1 kg DM/day while total intake ranged from 2.7 to 2.8 kg DM/day. Ruminal pH and temperature in cattle fed various levels of post-FYeB were not significantly different among treatments. Total volatile fatty acids (VFA) and VFA profiles were not altered by different levels of post-FYeB. Post-FYeB addition into diet did not change bacteria and protozoal populations ( P > 0.05). Thus, the inclusion of post- FYeB as a replacement of SBM in ruminant diets up to 100% is suggested. %A Cherdthong, A. %A Sumadong, P. %A Foiklang, S. %A Milintawisamai, N. %A Wanapat, M. %A Chanjula, P. %A Gunun, N. %A Gunun, P. %P 238-243 %R 10.22358/jafs/110992/2019 %U https://doi.org/10.22358/jafs/110992/2019