HAYWARD*, L.S.; WINGFIELD, J.C.: Laying Japanese Quail transfer corticosterone to egg yolk

Exposure to maternal stress and elevated gluccocorticosteroids often has long term debilitating effects on developing mammals and fish. We addressed the question of how, if at all, elevated gluccocorticoids in the circulation of laying birds affect the development and phenotype of their offspring. First we tested for transfer of corticosterone (cort) from maternal plasma to egg yolk. Laying Japanese Quail (Coturnix japonica ) were implanted with cort-filled silastic tubes which kept plasma levels of cort high for prolonged periods to mimic chronic stress. Concentrations of cort in the yolk of eggs laid by cort-implanted females were compared to concentrations of cort in the yolk of eggs laid by birds implanted with empty tubes. Six days after implantation levels of cort were significantly higher in the egg yolk of treated birds than controls, suggesting that transfer of corticosterone from maternal circulation to egg yolk does occur.