Sessions

Bile acids play a crucial role in regulating lipid metabolism in dogs; therefore, both their quantitative and qualitative alterations reflect the functional state of the gastrointestinal tract and the liver. Since the conversion of primary to secondary bile acids is largely mediated by the gut microbiota, psyllium, as a dietary fiber and prebiotic, may indirectly influence bile acid metabolism through its effects on intestinal function and microbial composition.

The aim of this study was to investigate how psyllium supplementation in healthy dogs affects serum bile acid levels compared to control measurements, the conversion ratio of primary and secondary bile acids, and the overall bile acid profile.

To this end, we performed a control experiment and a psyllium-supplemented trial, during which bile acid concentrations were determined from blood serum samples collected from healthy dogs. Following a 12-hour fasting period, blood samples were obtained after feeding at 10 time points during the control phase, whereas after 14 days of psyllium supplementation the sampling protocol was repeated with a reduced number of time points (7). Serum samples were analyzed using both clinical spectrophotometry for total bile acids and LC–MS/MS for compound-specific quantification of 15 individual bile acids.

Based on our results, the total bile acid concentrations measured by LC–MS/MS were consistently higher than those obtained with the clinical spectrophotometric method, both in the control and in the psyllium-supplemented trials. In the psyllium group, the postprandial total bile acid curves showed a different pattern compared to the control, and the conversion ratio of primary to secondary bile acids and the balance between primary and secondary bile acids were also altered as a result of psyllium supplementation.

The comparison of the two trials allowed the evaluation of psyllium’s effect on bile acid metabolism. Our findings suggest that psyllium supplementation modifies both the bile acid profile and its dynamics in dogs, which may hold clinical relevance for the characterization and management of gastrointestinal diseases. This observation may provide clinically relevant insights for the diagnosis and treatment of gastrointestinal disorders in dogs.