What research tells us about the effects of stocking density on pig welfare, behavior, and health, and how current standards compare to evidence-based recommendations.
Stocking density is one of the most significant controllable welfare variables in pig production. The evidence base consistently shows that current commercial stocking densities in many jurisdictions suppress natural behavior and increase harmful behaviors — the floor space required for a pig to simultaneously see, lie fully extended, stand comfortably, and approach food and water without competition significantly exceeds minimum regulatory requirements. The welfare case for reduced stocking density is supported by behavioral, physiological, and health outcome research. The economic case is more complex — lower density requires larger facilities per pig — but welfare-certified premium markets and reduced antibiotic costs partially offset the higher production cost.