PSVIII-22 - A probiotic blend improves fecal quality and enhances gut immunity in dogs with chronic diarrhea

Abstract: Probiotics have been fed to pets for their enhanced health benefits beyond the basic nutrition, as well as to manage diarrhea. Species and strains of probiotics and the combinations may elicit different beneficial effects in dogs. Therefore, the objective of this study was to evaluate the effects of a probiotic blend (2 strains of Bacillus subtilis and 1 strain of Bacillus amyloliquefaciens) on digestibility, fecal characteristics, fecal microbiota, and fecal metabolites in healthy dogs and dogs with chronic diarrhea (CD = dogs with intermittent diarrhea persisting for more than 3 months prior to study start that were otherwise clinically healthy). Twenty-two adult dogs (11 healthy, 11 CD; mean BW=14.1 kg; mean age=8.1 y) were enrolled in a cross-over design study, with two 3-week feeding periods and a 3-week washout between feeding periods. Protocols were approved by the facility’s Institutional Animal Care and Use Committee. Dogs were assigned to a control kibble or control kibble + probiotic blend (1.5 × 10⁶ CFU/g) top dressed on the food. Fecal scores were evaluated daily during each period. Fecal samples were collected during days 14 to 18 for nutrient digestibility. Fresh fecal samples were collected on days 17-18 for dysbiosis index and fecal metabolites measurements. All data were analyzed using the Mixed Models procedure of SAS. Probiotic supplementation did not affect digestibility, dysbiosis index, or fecal volatile fatty acid concentrations in both healthy and CD dogs. Fecal scores were lower (P< 0.05; firmer stool) when dogs consumed the probiotic blends for both healthy and CD groups. In dogs with CD, consumption of the probiotic blend resulted in greater (P< 0.05) fecal IgA concentrations. These data demonstrate that the probiotic blend may elicit intestinal health benefits by improving stool quality and enhancing gut immunity, especially in dogs with CD.