Broiler breeders are the parent birds of commercial meat chickens. They are genetically selected for rapid growth in their offspring but must be severely feed-restricted to maintain reproductive capacity, creating a profound welfare paradox.
Feed restriction in broiler breeders causes chronic hunger that is experienced as a sustained aversive state. Birds on restricted rations spend disproportionate time in food-seeking behaviours, demonstrate elevated aggression around feeding, and show physiological stress responses. Behavioural evidence including the finding that restricted breeders will work harder to access food than their satiated counterparts demonstrates subjective hunger. The welfare problem is inherent to the genetics of fast-growing broiler lines and cannot be resolved without selecting for slower-growing breeds.