The physical design of pig housing has profound welfare implications, with research showing that space allowance, substrate provision, and group size significantly affect behavioral and health outcomes.
Pig pen design welfare is an area where small changes in infrastructure deliver large welfare improvements. The provision of straw bedding or other rooting substrate is perhaps the single most evidence-supported intervention in pig welfare science - environments with manipulable substrate have dramatically lower rates of tail biting, ear biting, and other damaging behaviors that represent welfare emergencies in affected pigs. Space allowance affects both physical welfare through reduced injury and behavioral welfare through ability to establish social order and perform natural behaviors. Modern welfare-positive barn design incorporates these requirements and demonstrates that welfare and productivity are compatible.