Laying hens in conventional battery cage systems endure severe confinement that prevents nearly all natural behaviors, making commercial egg production one of the most welfare-significant practices in animal agriculture.
Battery cage hens experience some of the most severe behavioral deprivation of any farmed animal. Hens have strong motivations to perch, dust bathe, and lay eggs in private nesting sites - all impossible in battery cages. Research shows that hens will work extremely hard to access nesting boxes before laying, indicating the strength of this drive. Foot abnormalities from wire flooring cause chronic pain. The psychological state of hens in these conditions - measured through cognitive bias tests analogous to human pessimism assessment - shows evidence of chronic negative affective states. The scale of the problem, affecting billions of individual birds, makes this one of the largest welfare crises in animal agriculture.