A study was conducted using commercial broiler breeders with the males fed a diet containing, either 120/0 or 140/0 protein and body weight maintained at either 900/0 or 1000/0 of that recommended by the primary breeder (fed separately), or allowed to eat from the female feeders (controls). Female feeders in the separately fed pens were equipped with especially designed grills, which denied access to the males. The male feeder in these pens was elevated so that females were denied access. Males fed separately (body weight 90% or 1000/0, and dietary protein 120/0 or 140/0) had a significantly higher percentage fertility (4.20/0) than males allowed to eat with the females. No differences in percentage fertility were found among the four separately fed groups. No differences were noted in percentage hatch of fertile eggs among any of the treatment groups. Males eating from the female feeders had significantly heavier body weights and testes weights at 65 weeks of age than breeder males in the separately fed, groups. Mean body weights were 3819g and 4773g at 35 weeks of age, and 4192g and 5443g at 65 weeks of age for males eating separately and eating with the females, respectively. Furthermore, males in the control group had significantly larger breast angle measurements when compared with the separately fed males. No differences were observed in foot scores and semen concentration among males in the various treatment groups. / Master of Science