Farm Animals

Pig Regrouping Stress Reduction Strategies

Regrouping pigs causes fighting and stress that can be reduced through management and environmental strategies.

Key Facts

Pigs establish dominance hierarchies through fighting when new groups are formed
Regrouping injuries include lacerations, lameness and occasionally death
Fighting peaks in the first 24-48 hours after regrouping and gradually subsides
Providing deep straw, multiple feeding points and visual barriers reduces fighting intensity
Penning unfamiliar pigs together in the dark or in a novel environment can reduce initial aggression

Welfare Considerations

Regrouping stress causes acute pain from fighting injuries and chronic social anxiety as new hierarchies are established. Reducing the frequency of regrouping events, keeping stable social groups and providing appropriate environments are the most effective welfare interventions. Novel group formation methods show promise but are not yet standard practice.

What You Can Do

Support pig welfare standards that limit the frequency of regrouping events
Choose pork from farms using stable group management systems
Advocate for research into low-stress regrouping methods as a welfare priority
Learn about pig social behaviour and stress from BPEX and Compassion in World Farming