Farm Animals

Pig Social Hierarchy and Aggression Management

Managing pig social hierarchies and aggression to reduce welfare costs in group housing systems.

Key Facts

Pigs establish dominance hierarchies through aggressive interactions
Re-grouping unfamiliar pigs causes fighting and injury, particularly at the skin
Stable social groups with familiar individuals show significantly less aggression
Space allowance, feeding points, and hiding barriers reduce competition-related aggression
Genetic selection for lower aggression is an emerging welfare strategy

Welfare Considerations

Social aggression causes significant acute and chronic welfare costs in pigs, and system design that supports stable social groups is a priority intervention.

What You Can Do

Support farms using stable social grouping practices
Advocate for minimum space allowances that reduce competition aggression
Choose pork from farms with aggression management certified by welfare assurance