Research on the companion animal gut microbiome is revealing connections between diet, gut bacteria, immunity, and behaviour with significant welfare implications.
The gut microbiome represents a frontier in companion animal welfare science. Research is establishing that the trillions of microorganisms living in the gastrointestinal tract of dogs and cats influence not just digestive health but immune function, inflammatory responses, and via the gut-brain axis, behaviour and emotional state. This means that welfare problems including anxiety, immune-mediated disease, and chronic gastrointestinal conditions may have microbiome dimensions that are currently underappreciated in clinical practice. Diet is the most practical lever available to owners: diverse, minimally processed diets that include appropriate fibre sources support microbiome diversity. Judicious use of antibiotics — avoiding unnecessary courses and supporting microbiome recovery after necessary treatment — is equally important. The field is developing rapidly and clinical applications are expanding.