Research into pig cognition and behavior has generated clear evidence about what enrichment materials actually improve pig welfare in commercial farming.
The gap between what welfare science demonstrates about pig enrichment and what commercial farms typically provide is stark. Pigs are motivated to root with an intensity comparable to hunger — deprivation of this behavior causes genuine distress that manifests in redirected aggression and tail biting. The research is clear: straw, compost, hay, or other substrates that pigs can root through and manipulate are dramatically more effective than suspended chains or rubber objects. The primary barriers are not knowledge but economics and facility design — problems that are solvable through policy requiring adequate enrichment substrates.