The canine gut microbiome plays a critical role in immune function, mental health, and overall wellbeing. Diet is the most significant modifier of microbiome composition in companion dogs.
An optimal gut microbiome supports immune resilience, reduces inflammation, and may influence mood and stress responses through the gut-brain axis. Dogs on inappropriate diets lacking fiber diversity show reduced microbiome diversity associated with inflammatory bowel disease and immune dysregulation. Frequent antibiotic exposure disrupts microbiome recovery and may contribute to behavioral changes including increased anxiety. Feeding variety within a balanced diet supports microbial diversity, though abrupt dietary changes cause gastrointestinal distress requiring gradual transitions. This emerging area of veterinary nutrition science is providing new tools for optimizing companion animal welfare beyond traditional disease prevention.