The gut microbiome of companion animals is increasingly recognised as a mediator of health and welfare, with diet, stress, and antibiotic use all significantly affecting microbiome composition.
Companion animal gut microbiome research is rapidly translating into welfare-relevant insights. The microbiome mediates immune function, mental health, and gastrointestinal welfare — disruption of its balance has consequences that extend well beyond digestive symptoms. Antibiotic treatment, while medically necessary in appropriate contexts, causes microbiome disruption that should be considered alongside therapeutic benefits. Dietary patterns that support microbiome diversity — variety, fibre, fermented foods — correlate with better health outcomes across multiple organ systems. The connection between the gut-brain axis and companion animal behaviour and anxiety adds a psychological welfare dimension to microbiome management that is only beginning to be understood clinically.