Nordic Red dairy cows ruminal and fecal bacteria, 16S rRNA gene V4 region amplicons

Six multiparous Nordic-Red dairy cows were ranked during their 1st lactation as efficient (n=6) or non-efficient (n=6) based on residual energy intake (L-REI and H-REI) phenotype. Cows were fed two diets, based on grass silage supplemented with either low (30% of DM, diet LC) or high (50% of DM, diet HC) proportion of concentrates. The objective of this experiment was to evaluate two hypotheses: 1) animal production traits differ between cows with different feed efficiency phenotype 2) feed efficient dairy cows produce less methane than non-efficient cows, and differences could be linked to rumen and/or fecal microbiome.

选取12头经产北欧红奶牛，于其第一泌乳期根据剩余采食量（Residual Energy Intake, REI）表型分为高效组（L-REI，n=6）与低效组（H-REI，n=6）。试验奶牛饲喂两种以青贮牧草为基础的日粮，分别添加占干物质（Dry Matter, DM）30%的低比例精饲料（记为LC日粮），或占干物质50%的高比例精饲料（记为HC日粮）。本试验旨在验证两项假说：1）不同饲料利用效率表型的奶牛其生产性状存在差异；2）饲料高效利用奶牛的甲烷排放量低于低效奶牛，且该差异可能与瘤胃（Rumen）及/或粪便微生物组（Fecal Microbiome）相关。