How the gut microbiome influences animal health, behavior, and welfare across farmed and companion species.
The gut microbiome represents a fascinating frontier in animal welfare science. The bidirectional relationship between stress, microbiome health, and immune function means that welfare conditions shape microbiome composition, which in turn shapes health and behavior. Animals raised in high-stress, low-complexity environments show microbiome profiles associated with increased disease susceptibility and behavioral dysregulation. This creates a biological mechanism by which poor welfare compounds into worse welfare — and conversely, why improving conditions delivers benefits that cascade through multiple health systems.