Meat is an important food source, the nutritional composition of which, in conjunction with its desirable taste, positively affects human development and health. From a veterinary point of view, meat obtained from food-producing animals is also a potential reservoir for foodborne pathogens, including Escherichia coli. The prevalence and spread of antibiotic-resistant E. coli represent a threat to public health. For these reasons, the aim of this work was to identify the isolates obtained from food processing plants and to confirm the presence of E. coli species based on phenotypic and genotypic expression. The susceptibility of the investigated strains to antibiotics and their combinations was determined using the modified microdilution method. Dominant resistance was detected against ampilicin, tetracycline, cotrimoxazole, ampilicin + sulbactam, ciprofloxacin, and cefuroxime. Resistance to ertapenem, cefotaxime, tigecycline, and ceftazidime was also detected sporadically. Frequent mechanism responsible for resistance was generated an incomplete fluoroquinolone resistance induced by mutation and penicillinase with low enzyme expression. The occurrence of multidrug-resistant strains was also detected. Selected E. coli isolates were subjected to detection of genes encoding resistance to tetracyclines (tetA and tetB) and quinolones (qnrA, qnrB, and qnrS) by PCR. The tetA gene was confirmed in 68 % of the isolates, and the tetB gene in one isolate. The prevalence of the qnrA gene was found to be 29 % in the examined isolates. Two isolates showed the presence of the qnrS gene. The qnrB gene, as well as a combination of the qnrA and qnrB genes, was detected in one isolate.
