The phase-out of conventional battery cages for laying hens represents one of the most significant animal welfare policy achievements of recent decades. Understanding what has worked, what has not, and what remains to be done is essential for advocates and policymakers.
The battery cage phase-out demonstrates both the achievability and the complexity of major animal welfare reform. Where it has been successfully implemented, it represents an unambiguous welfare improvement — hens can extend their wings, perch, dustbathe, and exhibit a more complete behavioural repertoire. However, alternative systems introduce new welfare challenges. Keel bone fractures — caused by falls from perches in cage-free systems — affect 50-80% of commercial hens in some studies, causing chronic pain. Feather pecking and cannibalism are harder to manage without the physical separation cages provide. The welfare lesson is that system transitions require parallel investment in management training, monitoring, and breed selection to prevent trading one set of welfare problems for another.