Social aggression in pigs causes significant welfare harm through injuries, and understanding pig social behavior enables management strategies that reduce conflict without compromising production.
Pig social aggression welfare requires understanding the distinction between the inevitable hierarchy-establishing aggression when pigs are first mixed and the ongoing conflict that reflects inadequate management conditions. The brief but intense fighting when unfamiliar pigs are mixed cannot be entirely eliminated without maintaining completely stable groups throughout production - difficult but achievable through careful management planning. Ongoing chronic aggression in established groups indicates inadequate resources - insufficient space, feeding stations, or enrichment that causes persistent competition. Tail biting is a distinct problem - not dominance aggression but redirected foraging behavior that indicates behavioral frustration with the environment rather than social problems. Understanding these distinctions allows targeted interventions for each aggression type.