The parent flocks that produce broiler chickens are intentionally food-restricted to prevent obesity, creating chronic hunger that represents one of the most severe welfare problems in poultry.
Broiler breeder feed restriction creates chronic hunger that welfare scientists consider one of the most serious welfare problems in commercial poultry. The birds are genetically programmed for rapid growth and have correspondingly high appetitive drive. Restricting their intake to 30-50% of ad libitum consumption does not reduce their hunger drive — it creates persistent motivation frustration expressed in food-seeking stereotypies, aggression at feeders, and behavioral despair. The welfare harm is deliberate by design: restriction is necessary to prevent the metabolic disease that occurs when these birds eat freely. The solution requires either alternative genetic lines with lower feed efficiency drive or dietary approaches that allow satiety without excessive caloric intake. Neither solution is yet commercially mainstream, but welfare-motivated research is progressing.