Predictive value of palpation per rectum vs milk and serum progesterone levels for the diagnosis of bovine follicular and luteal cysts.

Diagnosis of bovine follicular and luteal cysts by palpation per rectum was compared with diagnosis by progesterone status, as determined by an enzymeimmunoassay (EIA). A 2x2 contingency table analysis allowed the calculation of predictive value, sensitivity and specificity for the palpation diagnosis of both cyst types. The results were 75.0, 61.9 and 50.0% for follicular cysts and 35.1, 50.0 and 61.9% for luteal cysts, respectively. The EIA results were compared to radioimmunoassay (RIA). The predictive value for a low progesterone determination (<5ng/ml) was 91.8% and for high progesterone (5ng/ml or >) it was 83.3%. The sensitivity and specificity for the EIA were both 88.2%. Within the EIA system, milk and serum samples agreed a total of 85 out of 87 times (97.7%). Definitive diagnosis of follicular or luteal cysts should not be based upon palpation per rectum alone. The EIA was found to be the better definitive diagnostic technique.