High-Grain Diet Feeding Altered Blood Metabolites, Rumen Microbiome, and Metabolomics of Yaks

Currently, information available on the comprehensive changes in rumen bacteria and metabolites of yaks fed high-grain diets is limited. This study aimed to investigate effects diet feeding blood metabolites, microbiome, metabolomics by using 16S rDNA gene sequencing liquid chromatography–mass spectrometry (LC/MS). Here, fourteen healthy male (body weight, 249.61 ± 8.13 kg) were randomly assigned two different diets: a hay (0% grain, CON, n = 7), or (70% HG, 7). At 74th day treatment, ruminal fluid samples collected for analyses. The HG increased lipopolysaccharides (LPS), aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), haptoglobin (HPT), serum amyloid-A (SAA), interleukin-1β (IL1-β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) concentrations (p < 0.05). Compared with CON diet, decreased pH 0.05), total volatile fatty acids concentration, proportion butyrate relative abundance Firmicutes Saccharibacteria higher while Bacteroidetes was lower 0.05) group than those group. genus level, Christensenelaceae_R-7_group, Ruminococcaceae_NK4A214_group, Lachnospiraceae_NK3A20_group, Acetitomaculum group, biogenic amines (histamine, tyramine, putrescine), common amino (phenylalanine, threonine, serine, etc.), arachidonic acid (prostaglandin H2, prostaglandin E2, 12(S)-HPETE, etc.). Collectively, these findings demonstrate that altered microbiota as well potentially damaged their health induced inflammation yaks.