Hen Perch Use and Bone Health: Why Perching Matters for Laying Hens

Access to perches is one of the most important welfare provisions for laying hens, with profound effects on bone health, natural behaviour expression, and quality of life.

Key Facts

Laying hens have a strong motivation to perch, particularly at night — perch deprivation causes frustration and distress
Keel bone fractures affect 50–80% of laying hens in commercial flocks, representing one of the most significant welfare problems in the egg industry
Perch use strengthens bones through mechanical loading — hens with perch access have denser, stronger bones than cage-housed birds
Keel bone fractures are painful and associated with altered gait, reduced activity, and lower egg production
In aviary systems, hens use multiple perch levels for roosting, moving between tiers, and escaping conspecific aggression
Perch design matters: round wooden perches of 3–4 cm diameter are preferred over flat or metal alternatives
Falls from perches at night contribute to keel bone fractures — perch spacing and height influence fall risk
Enriched colony cages provide perches but at lower provision than aviary systems — keel bone fracture rates remain high in enriched cages

Welfare Considerations

Perch access and keel bone health are deeply interconnected welfare issues for laying hens. Hens are strongly motivated to perch, particularly at dusk and through the night — this is an evolutionarily conserved behaviour linked to predator avoidance. Deprivation causes chronic frustration, and the absence of bone-strengthening mechanical loading from perch use contributes to the epidemic of keel bone fractures that now affects the majority of commercial laying hens in most systems. Keel bone fractures cause pain that affects behaviour for weeks to months. Improving perch design, placement, and accessibility can reduce fracture incidence: avoiding perches directly below higher tiers (which create a fall hazard), providing adequate perch space per bird, choosing materials that provide secure grip, and training pullets to use perches before housing in laying facilities all help. Housing system reform toward well-designed aviary or free-range systems with appropriate perch infrastructure represents the most effective welfare improvement, though even within existing systems, perch optimisation can reduce harm.

What You Can Do

Choose eggs from systems with documented low keel bone fracture rates where this data is available
Support egg industry welfare programmes that specifically target keel bone fracture reduction
Advocate for welfare standards that include keel bone scoring as a mandatory audit measure
Support research into perch design innovations that reduce falls and keel bone fracture incidence
If keeping backyard hens, ensure they have access to appropriate perches at a comfortable height with secure footing
Raise awareness that keel bone fractures are one of the highest-prevalence welfare problems in egg production