Progesterone concentrations in peripheral plasma of Menz sheep during gestation and parturition

This study is aimed to characterize progesterone profiles of Menz ewes during gestation with intent to gain insight into applied clinical endocrinology in early pregnancy diagnosis and monitoring of prenatal reproductive wastage. Mean hormone concentrations were basal, but increased and remained elevated throughout pregnancy, differing between ewes and stage of gestation, but not due to number or sex of foetuses. Progesterone production was also lowly related to weight of lambs at birth. Progesterone level increased throughout pregnancy. This was followed by a gradual decline during the last 3 weeks. It was concluded that elevated progesterone levels 18 to 22 days after mating indicate continued luteal function and/or pregnancy in Menz sheep.