Milk Progesterone Assays in Pregnancy Diagnosis

Abstract

The results of several studies2,3,4 on the accuracy of early pregnancy diagnosis by determination of milk progesterone levels are shown in Table I. Thus, both methods are reported to be of similar accuracy, approaching 100 percent for the nonpregnant cow and 85 to 90 percent overall if both pregnant and nonpregnant diagnoses are combined. This is not surprising as pregnancy diagnosis by palpation 20 to 22 days following breeding depends on the presence or absence of a corpus luteum and/ or changes (edema and tonus) related to its presence or absence. The presence and amount of progesterone in the milk is also a function of the presence or absence of a corpus luteum and/or its age.