Scientific evidence on pig enrichment has expanded dramatically, identifying effective materials and designs that reduce tail biting, stereotypic behavior, and aggression while improving welfare in commercial production.
Pig enrichment science has moved from generic 'manipulable material' requirements to specific evidence about what works. The finding that pigs rapidly habituate to unchanging enrichment means that the regulatory requirement to provide material is insufficient without implementation guidance on material type and renewal. Straw and other organic, edible materials dramatically outperform metal chains and rubber toys in reducing tail biting frequency. The welfare business case for effective enrichment is strong - tail biting outbreaks cause significant production losses and require intensive management. Farms implementing high-quality rotational enrichment programs report both better welfare indicators and better economic outcomes. The evidence base now exists to specify effective enrichment in legislation rather than accepting minimal compliance.