Dose of progesterone and allantoic fluid volume in conceptuses in ovariectomised goats

The volume and composition of fetal fluids in conceptuses from untreated goats and from ovariectomised goats in which pregnancy was maintained with a high (0-76 mg per kg body weight) or low (0-35 mg per kg body weight) dose of progesterone, were determined. The mean allantoic fluid volume per conceptus was similar in the untreated goats (77-0+/-13-49 ml) and the ovariectomised goats which received the higher dose of progesterone (81-4+/-18-24 ml) but was significantly greater in the ovariectomised goats which received the lower dose of progesterone (251-5+/-66-49 ml). The increase in allantoic fluid was associated with a rise in K+ concentration.