Graduate Research Assistant Texas A&M University College Station, Texas, United States
Abstract: Background– Acute diarrhea (AD) is a common condition in dogs associated with transient microbiota shifts. It remains unclear whether the fecal metabolome or the conversion of bile acids by key bacteria like P. hiranonis are altered in AD. Fecal long chain fatty acids and sterols are potential markers of mucosal cell shedding and epithelial cell damage.
Objective– Evaluate fecal bile acids (BA), long-chain fatty acids (FA), sterols, and P. hiranonis in dogs with AD.
Animals– Ten dogs with uncomplicated AD without antibiotics and 42 healthy controls (HC).
Methods– Retrospective observational study using archived samples characterized with AD lasting five days or less. AD samples were analyzed at presentation, one-week, and one-month follow-up. HC were collected at a single time point. Fecal BA, FA, and sterols were measured using mass spectrometry-based assays. P. hiranonis was measured using qPCR.
Results– The ratio of secondary to primary BA and P. hiranonis abundance were not different from HC at presentation. Fecal cholesterol was increased at presentation (median: 12.7 μg/mg) compared to HC (median: 2.5 μg/mg; p = 0.003, Wilcoxon). At one-month follow-up, cholesterol decreased (median: 4.5 μg/mg) but remained higher than HC (p = 0.001, Wilcoxon). Arachidonic, stearic, docosanoic, and nervonic acids were increased at presentation (p = 0.04, Wilcoxon), but not different from HC at one-month.
Conclusions and Clinical Importance– AD is associated with transient alterations in fecal FA and sterols, notably increased cholesterol, arachidonic, and nervonic acids, suggesting intestinal epithelial cell damage. However, P. hiranonis and BA conversion was unchanged.
