Comparative Accuracy of Cow-Side Tests for Detection of Subclinical Mastitis

Subclinical mastitis (SCM) greatly influences the udder health, lowers milk quality and quantity.The gross clinical signs being absent, it is left undetected leading to high economic impacts on dairy farming.Cow-side indirect tests are employed for diagnosis besides the bacteriological culture (BC) as the gold standard.This study aimed to evaluate the diagnostic validity/ accuracy of cow-side tests like California Mastitis Test (CMT), Somatic Cell Count (SCC) and Electrical Conductivity (EC) with BC as the gold standard test for SCM detection.Growth on culture media of at least one colony of a major pathogen was taken as the criterion for a positive test.A total of 410 quarter milk samples were tested.The accuracy and Cohen's kappa values for CMT were 70.98% and 0.42, for SCC 76.83% and 0.56, and for EC 53.45% and 0.09.The Receiver Operating Characteristic analyses showed the area under curve for CMT, SCC and EC as 78.10%, 81.20% and 59.90%, respectively.Both CMT and SCC had a good agreement with the gold standard test with SCC showing superiority over CMT in terms of diagnostic validity/ accuracy.Thus, the study endorsed SCC as the first choice for accurate detection of SCM in dairy cattle followed by CMT. HIgHlIgHTSm CMT, SCC and EC were compared for subclinical mastitis detection.m SCC was superior to CMT with more kappa value and area under curve.