The shift from conventional battery cages to enriched colony cages and barn systems represents ongoing welfare improvement for laying hens, with different systems offering distinct advantages and limitations.
No current commercial laying hen system is welfare-perfect. Colony cages prevent many natural behaviours despite providing more than battery systems. Barn systems enable normal movement but create feather pecking risks without excellent management. Free-range welfare depends heavily on whether hens actually use outdoor access and the management quality indoors. Keel bone fractures are a significant welfare problem across multiple systems, particularly where perch height creates fall risk. The welfare hierarchy generally favours free-range and organic systems managed to high standards, but all systems require continued improvement and research.