Dust bathing is a fundamental behavioural need in hens, and its deprivation in cage systems causes distress expressed through sham bathing on wire floors.
Dust bathing deprivation causes clear behavioural frustration in hens. The vacuum dust bathing seen in cage systems is not a substitute and does not provide the physiological or psychological benefit of genuine dust bathing in appropriate substrate. Providing adequate litter depth for dust bathing in all commercial systems is a feasible and important welfare improvement that transforms hen behaviour and wellbeing.