Farm Animals

Pig Group Housing Aggression Management

Mixing unfamiliar pigs is a major source of acute welfare compromise, requiring careful management to minimize injuries.

Key Facts

Regrouping unfamiliar pigs triggers aggression lasting 24 to 72 hours
Injuries from fighting include ear tears, skin lesions, and limb wounds
Pheromone treatments and nose rings reduce but do not eliminate regrouping aggression
Higher space allowances and resource provision reduce competition-related aggression
Social stability once established leads to minimal ongoing aggression in stable groups

Welfare Considerations

Pigs in regrouping situations experience acute stress, fear, and physical injury. Management systems that minimize regrouping events and provide adequate space significantly improve welfare.

What You Can Do

Support pork from farms that minimize pig mixing and regrouping
Advocate for space allowance standards that reduce competition and aggression
Choose farms that keep pigs in stable groups from weaning to slaughter