Early Pregnancy Diagnosis by Estimation of Serum Progesterone in Cows

An early pregnancy has been detected in cows by serum progesterone estimation using standard Radio Immune Assay (RIA) technique. Serum P₄ was estimated on 22^nd day post insemination in cows. The mean serum progesterone level on 22^nd day post insemination of pregnant cows was 4.96±0.43 ng/ml whereas in non-pregnant cows it was 1.67±0.25 ng/ml. The accuracy of pregnancy diagnosis by RIA was 87.5% and 100% in pregnant and non-pregnant cows, respectively. The serum progesterone estimation as early as 18 to 22^nd days post insemination/natural service can be used as an effective managemental tool to detect early pregnancy or non-pregnancy in cattle to take appropriate remedial measures.