Persistence of pregnant mare serum gonadotrophin in plasma of Japanese quail (Coturnix coturnix japonica)

Abstract

Pregnant mare serum gonadotrophin (PMSG) is currently being used to develop a hormone regime that will stimulate reproductive development in Japanese quail (Coturnix coturnix japonica). In this study, the persistence of PMSG in quail plasma was examined after a single injection of the hormone (500 IU). Plasma concentrations of PMSG increased to a peak 12 h after injection and declined to approximately 50% of peak concentrations 24 h after injection. Pregnant mare serum gonadotrophin concentrations declined gradually thereafter and had not returned to basal levels by 96 h after injection. Cloacal diameter, and ovarian and oviducal mass, had increased significantly by 96 h after injection. The persistence of PMSG in quail plasma has implications for the use of the hormone in future regimes stimulating reproductive activity in birds.