Enriched colony cages replaced barren battery cages in the EU from 2012, but remain controversial as welfare improvements are limited compared to cage-free systems.
Enriched colony cages provide more space and some behavioural resources than battery cages but still severely restrict movement, prevent normal wing flapping, and limit social behaviour. The nesting and dust bathing provisions are often inadequate for flock size. Barn and free-range systems provide substantially better welfare outcomes for the same species. Consumer pressure and retailer commitments are driving faster cage-free transitions than legislation requires.