Evaluation of the Mas-D-Tec equipment in the field diagnosis of subclinical mastitis in cattle

Abstract

In order to compare the Mas-D-Tec (electrical conductivity) equipment with the California Mastitis Test (CMT) in the field diagnosis of bovine subclinical mastitis, a controlled study was carried out using these two diagnostic techniques. The study used animals with more than 30 and less than 300 days of lactation belonging to four cattle units located in the municipality of San Jose de las Lajas, Mayabeque province. To perform the study under laboratory conditions, samples between 10 and 20 ml of 420 functional quarters were taken. They were sent to the clinical pathology laboratory UNAH for their immediate processing and they were evaluated in parallel by the California Mastitis Test and the Mas-D-Tec equipment. In order to carry out the study in the field, 172 functional quarters were sampled, being processed in parallel by CMT and MD. In both studies, the concordance index between the two methods (Kappa) was determined. In the laboratory study, 93.7 % of the quarters evaluated as negative by CMT (- and Traces) were also reported negative by the MD equipment (scale from 1 to 4). It is also reported that 78 % of the quarters reported as positive by CMT (+, ++ and +++ scale) were reported as positive by the MD equipment (5, 6, 7, 8 and 9 scale), obtaining a Kappa index of 0.71 and demonstrating a Considerable level of agreement between both methods. In the field study, the results were similar, with a Kappa index of 0.65 and a Considerable level of agreement in both methods.