What the science says about the most effective enrichment materials for improving pig welfare in commercial systems.
The science of pig enrichment provides clear guidance that is systematically underimplemented in practice. Pigs prefer rooting substrate over all other enrichment types, yet legislation allows facilities to fulfill enrichment requirements with hanging chains that pigs engage with only briefly. Closing the gap between what we know enriches pig welfare and what regulations require is one of the most tractable improvements in livestock welfare policy. The evidence base for substrate enrichment is strong enough to justify requiring it, with production data showing that reduced tail biting and improved welfare also reduce economic losses.