Effect of Delayed Maturity and Carcass Fat on Reproductive Performance of Broiler Breeder Pullets

Abstract

MOST experiments involving restricted feeding of pullets show an increased productivity and egg size when sexual maturity is delayed sufficiently (Fuller and Dunahoo, 1962; Bletner, 1963; Strain et al., 1965). The increase is usually manifested by a shortening of time required to achieve peak production and maximum egg size and a sustained higher rate of production. Since restricted feeding results in both delayed maturity and a leaner carcass, it is logical to question which of these phenomena exerts the greatest influence on the productivity of pullets. There may also be a confounding seasonal effect. Bruins (1958) was able to increase the productive life of hens by various methods of restriction during the growing period even though there was little delay in sexual maturity. In his experiments extremely high temperatures were encountered shortly after housing the pullets and this was accompanied by increased mortality among the full-fed groups. He attributed this…