Early pregnancy diagnosis in the ewe, based on milk progesterone levels

摘要

Summary. Plasma and milk progesterone concentrations in pregnant sheep (18–22 days after mating) were similar, about 3·7 ng/ml whereas values in non-pregnant sheep were <1 ng/ml. Lambing results indicated identical accuracy for both methods (82 and 84% in 2 flocks). The accuracy was 92–100% for ewes diagnosed non-pregnant in the breeding season, but for ewes tested in the non-breeding season the diagnosis of non-pregnancy according to milk progesterone levels was only 50% accurate.