A series of experiments was conducted in order to develop a feeder grill that would allow broiler breeder males, but not females, to eat. Females are typically excluded from male feeders by increasing the height of the feeder. However, male feeder heights that exclude most females increase the time required for males to consume a given amount of feed 19 to 60%. Typical male feeder height from floor to feeder pan lip in commercial practice is 55 cm, which is about the distance from floor to the head of the male in an erect posture. Females measure about 40 cm in an erect posture. Because the necks of males (8.0 cm) are longer than those of females (6.3 cm), the lip of male feeder pans was extended horizontally 12.7 cm with a wire mesh on the assumption that females could not stretch their necks enough to reach the feed. However, the females learned quickly to perch on the extended lip and eat. Total exclusion of females from the male feeder, regardless of feeder height, was achieved by placing a horizontal upper mesh 5.6 to 10.2 cm above the extended lip, and connecting the upper mesh to the lower extended lip of the feeder with vertical bars spaced 5.1 cm apart. The horizontal upper mesh prevented perching by females and the 5.1-cm spacing of the vertical bars allowed males but not females to reach the feed by inserting their heads and necks up to their shoulders.(ABSTRACT TRUNCATED AT 250 WORDS)