Research on pig space allowances demonstrates clear relationships between stocking density and welfare outcomes, informing minimum standards for housing regulations.
Space allowance is one of the most directly measurable determinants of pig welfare in commercial production. Below minimum thresholds, pigs cannot perform natural behaviours, are forced into more aggressive interactions and show higher rates of stress-related health problems. Research using Welfare Quality protocols consistently documents better welfare outcomes at higher space allowances. The legal minimum is not optimal welfare but a floor below which problems become severe. Higher-welfare certification schemes that require additional space represent real welfare improvements. Consumers and retailers who specify minimum space requirements in supply chain standards drive meaningful change.