In laboratories at the University of Bristol, scientists have found that a molecule quietly produced by gut bacteria may hold the key to one of modern agriculture's most urgent dilemmas. Sodium butyrate, a short-chain fatty acid already present in the chicken gut, can reprogram developing immune cells to defeat dangerous pathogens — without the inflammatory damage or antibiotic dependence that have long defined livestock disease management. The discovery arrives at a moment when antimicrobial resistance is reshaping the boundaries of both animal and human medicine, suggesting that nature may h