Farm Animal Welfare

Pig Social Dominance and Pen Dynamics

Pig social hierarchies within pens have significant welfare implications, with subordinate individuals facing chronic stress and reduced resource access in poorly managed systems.

Key Facts

Pigs establish stable hierarchies within groups through agonistic interactions
Mixing unfamiliar pigs causes acute aggression lasting 24-72 hours until hierarchy established
Subordinate pigs in low space have reduced access to feeders, water, and resting areas
Minimising mixing events throughout production reduces cumulative aggression welfare costs
Multiple feed stations and refuges improve subordinate pig welfare in stable groups

Welfare Considerations

Social dominance in pigs creates welfare inequalities where subordinate individuals experience chronic stress, reduced resource access, and vulnerability to bullying. System design that reduces the welfare cost of dominance hierarchies through space, resources, and refuges is an important welfare intervention.

What You Can Do

Advocate for pen design standards that include refuge areas and multiple resource access points
Support research into management practices that minimise chronic stress in subordinate pigs
Choose pork from farms demonstrating monitoring of subordinate individual welfare