Abstract Restricting rate of gain and delaying sexual maturity of pullets are important considerations in producing a profitable broiler breeder flock. Most of the existing programs for rearing broiler pullets are based on some type of feed restriction, or the use of diets designed to limit nutrient intake starting around 8 to 10 weeks of age (Singsen et al., 1965; Waldroup et al., 1966; and Wright et al., 1968). Up to this time the birds are usually reared on a good quality starting ration which allows for fairly rapid rate of gain. In effect a stress of rapid growth is placed on the birds during the starting period followed by a stress during the growing period of limited nutrient intake. A more logical approach to growing pullets would seem to be a steady slow rate of growth from day of hatch till around 20 weeks of age. It is conceivable that…