The gut microbiome of dogs and cats significantly influences their immune function, mental health, and physical wellbeing, with diet, antibiotic use, and early life experience all shaping microbiome composition and welfare outcomes.
Companion animal microbiome research is advancing rapidly and has significant welfare implications. Disrupted microbiomes — from antibiotic overuse, ultra-processed diets, or inadequate early life microbial exposure — are associated with increased susceptibility to disease, inflammation, and potentially poor mental health. The welfare case for microbiome-conscious pet care includes judicious antibiotic use, dietary variety and fibre, and early life socialisation in environments with appropriate microbial diversity. While the science is still developing, the principle of supporting microbiome diversity through natural diet and environment is likely to produce welfare benefits that become clearer as research matures. Avoiding unnecessary antibiotics and ultra-processed pet foods are practical steps available to all pet owners.