Limited information is available regarding the metabolic consequences of intestinal
dysbiosis in dogs with acute onset of
diarrhea. The aim of this study was to evaluate the fecal microbiome, fecal concentrations of
short-chain fatty acids (SCFAs), as well as serum and urine metabolites in healthy dogs (n=13) and dogs with acute
diarrhea (n=13). The fecal microbiome, SCFAs, and serum/urine metabolite profiles were characterized by 454-pyrosequencing of the
16S rRNA genes, GC/MS, and untargeted and targeted metabolomics approach using UPLC/MS and HPLC/MS, respectively. Significantly lower bacterial diversity was observed in dogs with acute
diarrhea in regards to species richness, chao1, and Shannon index (p=0.0218, 0.0176, and 0.0033; respectively). Dogs with acute
diarrhea had significantly different microbial communities compared to healthy dogs (unweighted Unifrac distances, ANOSIM p=0.0040). While Bacteroidetes, Faecalibacterium, and an unclassified genus within Ruminococcaceae were underrepresented, the genus Clostridium was overrepresented in dogs with acute
diarrhea. Concentrations of fecal
propionic acid were significantly decreased in acute
diarrhea (p=0.0033), and were correlated to a decrease in Faecalibacterium (ρ=0.6725, p=0.0332). The predicted functional gene content of the microbiome (PICRUSt) revealed overrepresentations of genes for
transposase enzymes as well as
methyl accepting chemotaxis proteins in acute
diarrhea. Serum concentrations of
kynurenic acid and urine concentrations of
2-methyl-1H-indole and 5-Methoxy-1H-indole-3-carbaldehyde were significantly decreased in acute
diarrhea (p=0.0048, 0.0185, and 0.0330, respectively). These results demonstrate that the fecal
dysbiosis present in acute
diarrhea is associated with altered systemic metabolic states.