Protein and energy self-selection of turkey hens. Serum prolactin and luteinizing hormone concentrations

1. The incidence of broodiness was four times as high among turkey hens fed a complete control diet than among hens allowed to self-select their diet from two different feed sources, one being relatively high in protein and the other relatively high in energy (i.e. split-diet). 2. Among non-broody birds, hens fed the split-diet had a significantly lower serum prolactin concentration in the third month of production as compared to control hens. 3. Hens in their second season of egg production had significantly lower serum luteinizing hormone concentrations during the latter stages of egg production than did first season hens.