Introduction: The objective of this study was to determine the current profile of bacteria responsible for the infection of the mammary gland and to assess their sensitivity to selected β-lactam antibiotics.

Introduction: The study objective was to develop and evaluate a new TaqMan multiplex real-time PCR method for Salmonella, L. monocytogenes, and verotoxigenic Escherichia coli (VTEC) detection in slaughtered animal carcasses.Material and Methods: The procedure included an enrichment step, DNA extraction, and two multiplex real-time PCRs. The first PCR detected the invA and hly genes of Salmonella and L. monocytogenes respectively, the second the vtx1, vtx2, and eae genes of VTEC.Results: The validation of this method resulted in 100% relative sensitivity, specificity, and accuracy as compared to the reference ISO methods. The limit of detection per swab sample was established at 1 cfu for Salmonella and L. monocytogenes and 2 cfu for VTEC. The authors analysed 265 slaughterhouse-collected swabs from cattle, pig, and poultry carcasses. Among 125 from cattle, 51 were positive for VTEC, 29 for Salmonella, and 1 for L. monocytogenes. Among swabs from pig carcasses (n = 95), three, two, and one sample were positive for these pathogens respectively. None of the microorganisms tested for was identified in 45 samples of poultry origin.Conclusion: The obtained results showed that the method developed can rapidly identify the main bacterial pathogens that may contaminate carcasses of food-producing animals.