Broiler breeder hens and roosters are chronically feed-restricted to prevent the obesity caused by their fast-growing genetics — a practice that causes persistent hunger and is one of the most severe welfare problems in poultry production.
Broiler breeders experience chronic hunger that motivates extreme food-seeking behaviour — they consume non-food litter material, show stereotypic pecking, and become aggressive at feeding time. The severity of hunger motivation is demonstrated by preference tests showing birds accept significant punishment to access additional food. This welfare problem is not incidental but is deliberately engineered into the breeding system to maintain reproductive capacity in a genotype selected for obesity. Alternative genetic lines and management approaches that reduce hunger severity exist but adoption has been slow.