The gut microbiome of companion animals influences immunity, behaviour and mental health. Emerging research is revealing how diet, stress and environment shape the microbiome and thus welfare outcomes.
The microbiome-welfare connection represents a frontier in companion animal science with practical welfare implications. The gut-brain axis - the bidirectional communication between gut bacteria and brain function - means that gut health directly influences psychological welfare: anxious dogs have disrupted microbiomes, and disrupted microbiomes increase anxiety. This creates both a new lens on companion animal welfare and new intervention points. Dietary interventions to support microbiome diversity, judicious antibiotic use with probiotic support during recovery, and stress reduction as a gut health intervention are all welfare-relevant applications of this science. The field is developing rapidly and owners should watch for evidence-based rather than marketing-driven recommendations.