The design of pig housing has profound impacts on welfare, with enrichment, space, and social conditions determining whether pigs can express natural behaviors and remain healthy.
Barren, understimulating environments cause chronic stress, learned helplessness, and stereotypic behaviors in pigs - repetitive, purposeless actions like bar-biting that indicate poor mental welfare. Overcrowding leads to increased aggression and tail-biting, which can cause severe wounds. Pigs denied rooting opportunities show elevated cortisol and altered brain development. The good news is that relatively low-cost interventions - straw bedding, hanging chains, or rooting substrate - dramatically improve pig welfare outcomes.