Shemesh M, Ayalon N, Mazor T
J Reprod Fertil. 1979 May;56(1):301-4. doi: 10.1530/jrf.0.0560301.
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 less than 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.
怀孕母羊（配种后18 - 22天）的血浆和乳汁孕酮浓度相似，约为3.7纳克/毫升，而非怀孕母羊的值则低于1纳克/毫升。产羔结果表明两种方法的准确性相同（两个羊群中分别为82%和84%）。在繁殖季节被诊断为未怀孕的母羊，准确性为92% - 100%，但对于在非繁殖季节检测的母羊，根据乳汁孕酮水平诊断未怀孕的准确率仅为50%。
