Feed intake regulation for the female broiler breeder: In theory and in practice

The modern commercial broiler is the product of intensive genetic selection for rapid and efficient growth. An unintended consequence of this selective breeding has been the loss of the ability for self-regulation of feed intake to closely match the requirements for maintenance, growth, and reproduction. Thus, the broiler tends to overconsume feed, resulting in a range of metabolic and health problems related to the development of obesity. These problems progress with age and become a significant impediment to the production of parent stock. To manage this situation, broiler breeder birds must be subjected to severe feed restriction, beginning early in life, to ensure that appropriate BW and composition are achieved at critical phases of the production cycle. This review focuses on the female broiler breeder because this bird requires the most intensive management with respect to feed allocation throughout production to attain BW targets that ensure good livability and efficient egg and chick production. Background information is provided on the cellular and molecular mechanisms that regulate feed intake and energy expenditure in poultry. In addition, several examples are discussed with regard to the endocrine and metabolic consequences of different feeding regimens commonly used in the management of the female breeder during the rearing and egg-laying phases of production.