ICAR Technical Series no. 7 - Nitra Proc.

Different diagnostic measures for mastitis76QY [kg]; EC [mS/cm]5432100 50 100 150 200 250 300 350DIMQYECFigure 1. Physiological course of quarter milk yield (QY) [kg] and electricalconductivity (EC) [mS/cm], mean and standard error of the mean; DIM = days inmilk (n = 6 cows).is usually above 70 %. The PM’s demonstrate, that considering this material,30 to 40 % of all quarters are always misclassified. The number of PM’s forclinical mastitis, that are particularly low, do not indicate a high recognitionrate of clinical cases, but are the result of the high number of non-clinicalcases.DiscussionandconclusionUsing a retrospective analysis of electrical conductivity and lactationcorrected yield data, from quarter machine milk samples andcorresponding cyto-bacteriological findings, the diagnostic value of theseparameters in single usage or in combination, was calculated, in order toidentify mastitis cases, omitting clearly the influence factor of the milkinginterval. By means of these parameters on quarter machine milk level andusing appropriate analysis procedures, the identification of ca. 70 % of allsub-clinical new infections and of 40 % of all clinical mastitis cases isfeasible. Zero to 20 % of all non-diseased quarters were misclassified withthis method. Although an extension and consecutively an optimization ofthe analysis systems should promise better results, automatic analysissystems – integrated in milking devices – can not be expected to provide asecure early diagnosis of mastitis under the tested conditions. Actually,66Conference on "Physiological and technicalaspects of machine milking"