Effect of sequentially fed high protein, hydrolyzed protein, and high fiber diets on the fecal microbiota of healthy dogs: a cross-over study

Background: Dietary content and environmental factors can shape the gut microbiota, and consequently, the way the gut microbiota metabolizes fats, carbohydrates, and proteins, affecting overall health of the host. We evaluated the impact of 3 diets (all meat [raw], high-insoluble fiber dry extruded diet and hydrolyzed protein dry extruded diet) on the gut microbiota of healthy dogs in a cross-over sequential study. Results: We showed that diet can have an effect on the gut microbiome in dogs, which was influenced by the order of feeding. High-protein (all meat) diets were characterized by an increase in bacteria belonging to the Fusobacteria and Bacteroidetes phyla, whereas a high-insoluble fiber commercial diet correlated with increases in Firmicutes and Actinobacteria phyla. However, the individual dog’s baseline microbiota had the most impact on the magnitude and nature of the changes in response to dietary intervention. Conclusion: Our results suggest that the dog fecal microbiota is driven by protein and fiber composition to different degrees in individual animals, and targeted modification of these patterns could be useful in the modulation of the gut microbiota in different diseases.