ICAR Technical Series no. 7 - Nitra Proc.

Kroemker et al.Comparison of different diagnosticmeasures to identify bovine mastiticquarters at milking timeV. Kroemker, J. Hamann, N.T. Grabowski & F. ReineckeCentre for Food Sciences, Section of Milk Hygiene and Technology,Veterinary School Hannover,Bischofsholer Damm 15,D-30173 Hannover, GermanyE-mail: milch@lebensmittel.tiho-hannover.deA precise diagnosis of bovine mastitis is only possible by examination onquarter level. The pre-selection of quarters with changes in quarter milkyield and electrical conductivity depending on inflammatory processes,will be useful under economical aspects, particularly concerning thefollowing cyto-bacteriological examination. These parameters are alreadyavailable, especially in automatic milking systems.SummarySensitivity, specificity and probability of misclassification to predict thediagnosis of clinical and sub-clinical mastitis were calculated, using aretrospective analysis of both parameters in comparison to a cytobacteriologicalreference based on quarter foremilk samples. Ninty-six cowson two farms were part of the survey, over a period of at least one lactationper cow.Using analyzing techniques, based on consecutively or momentaryorientated surveys of the parameters, up to 70 % of all sub-clinical mastitiscan be identified, with a specificity of approximately 80 %.The results indicate that these techniques can be used as early automaticwarning systems, although they are not sufficiently precise to replace thecyto-bacteriological examination.Key words: Bovine, mastitis, diagnosis, milking, quarter yield, electricalconductivity.ICAR Technical Series - No 763