Dust-bathing is one of the most strongly motivated natural behaviours in chickens. Its prevention in cage and litter-less systems causes significant frustration and compromises feather and skin health.
Dust-bathing deprivation is one of the clearest examples of frustrated motivation in farm animal welfare science. Hens that cannot dust-bathe perform stereotypic vacuum sequences on wire floors - the behaviour is so strongly motivated it is performed even in the absence of appropriate substrate. This represents welfare compromise at a basic level: the animal is driven to perform a behaviour it cannot complete. Free-range and deep-litter systems that provide loose dry substrate allow hens to perform this behaviour and show notably lower indicators of frustration.