PSIX-12 Inclusion of dried distillers grains with solubles in Lespedeza or alfalfa-based diets for meat goats is associated with a unique ruminal microbiome

Abstract

Abstract This study evaluated the effect of replacement of corn and soybean meal with distillers dried grains with solubles (DDGS) in lespedeza or alfalfa-based diets on the ruminal microbiome of growing meat goats. A total of 36 meat goats with average body weight (BW) of 24 ± 1.8 kg were blocked by BW and randomly assigned to four isonitrogenous (18.0) and isocaloric (3.2 Mcal/ kg DM) diets in a completely randomized design for 60 days. The treatment diets were: (1) alfalfa-based diet (ALC; containing 40.5% alfalfa, 26% corn and 13% SBM), (2) alfalfa and DDGS (ALD; replacement of corn and SBM with DDGS), (3) Sericea lespedeza (SL)-based diet (SLC; containing 47.25% SL, 20% corn, 13% SBM), (4) SL and DDGS (SLD; replacement of corn and SBM with DDGS). At the end of the experiment, the goats were slaughtered and rumen contents were immediately sampled for 16S rRNA gene sequencing. Linear discriminant analysis (LDA) effect size (LEfSe) were used to detect differentially abundant taxa among treatments. The relative abundance of 11 taxa, including Ruminococcaceae UCG 002, Succinivibrionaceae UCG 002 and Prevotellaceae YAB2003 were reduced (LDA > 2; P < 0.05) while 62 taxa, including Ruminococcaceae UCG 013, Ruminococcaceae UCG 001, and Saccharofermentans were enriched (LDA > 2; P < 0.05) in ALD compared to ALC. Relative abundance of 35 taxa, including Ruminococcus YE281, Succinivibrio, and Lachnospiraceae ND3007 were reduced while 42 taxa, including Prevotellaceae UCG 003 and Ruminococcus were enriched (LDA > 2; P < 0.05) in SLD, compared to SLC. A total of 68, 35, 61, and 91 taxa were respectively detected ALC, SLC, SLD, and ALD, but not in other treatments. These results showed that inclusion of DDGS in lespedeza or alfalfa-based diet causes a shift in ruminal microbial community and is associated with a unique ruminal microbial community