Stocking density profoundly affects pig welfare. Evidence-based space allowances prevent the aggression, injury and stress caused by overcrowding in intensive systems.
Pig space allowances illustrate the gap between regulatory minimums and welfare-adequate provision. Minimum legal requirements across most jurisdictions are set below the thresholds at which welfare research consistently documents positive outcomes. The economic pressure to house maximum numbers per square metre drives practices that are legal but welfare-compromising. High-welfare systems that provide evidence-based space allowances demonstrate reduced disease, aggression and mortality — outcomes with economic as well as welfare value. Consumer demand for certified higher-welfare pork and legislative reform of minimum space requirements are the primary pathways to closing the gap between legal minimums and welfare-adequate provision.