Outcome-based welfare indicators measured directly on pigs — rather than inputs like housing specifications — provide more accurate and meaningful assessments of actual welfare status on farms.
Outcome-based welfare assessment represents a paradigm shift in how farm animal welfare is measured and enforced. A farm can technically comply with housing regulations while still housing pigs in conditions that cause widespread suffering — for example, providing enrichment materials that pigs rapidly destroy and that are not replaced. Measuring what is actually happening to pigs — tail lesion prevalence, lameness, aggression, positive behaviour expression — provides a more honest welfare picture than input compliance audits alone. The most effective welfare assurance systems combine both approaches, using outcome data to identify farms where compliance is not translating into good welfare.