Search

The global food chain may significantly promote the dissemination of bacteria resistant to antibiotics around the world. This study was aimed at determining the prevalence and genetic characteristics of Enterobacteriaceae with mcr -mediated colistin (CT) resistance in retail meat of different origins. Bacteria of the Enterobacteriaceae family carrying the mcr-1 gene were detected in 21% (18/86) of the examined samples, especially in turkey meat and liver originating from EU and non-EU countries (19%) and in rabbit meat imported from China (2%). The examined samples of the meat and liver of chicken and other poultry and of pork and beef were negative for the presence of bacteria carrying the mcr-1 to mcr-5 genes. A huge number of isolates belonging to Escherchia coli (n = 54), K lebsiella pneumoniae (n = 6), and Citrobacter braakii (n = 1) carrying the mcr-1 gene were obtained. Despite the high heterogeneity of the tested isolates, the mcr-1 gene was localized on only three types of plasmids (IncX4, IncHI2, and IncI2). The most frequent type of plasmid was IncX4, which carried the mcr-1 gene in 77% of E. coli and K. pneumoniae isolates from turkey meat and liver samples from the Czechia, Germany, Poland, and Brazil. Our findings indicate highly probable interspecies transfer of IncX4 and IncI2 plasmids within one meat sample. The co-resistance of plasmid-mediated CT resistance encoded by the mcr-1 and ESBL genes was detected in 18% of the isolates. Another noteworthy finding was the fosA3 gene coding for fosfomycin resistance in a multidrug-resistant isolate of E. coli from rabbit meat imported from China. The observed high level of Enterobacteriaceae with plasmids carrying the mcr-1 gene in retail meat reflects the need for Europe-wide monitoring of mcr -mediated CT resistance throughout the whole food chain. [ABSTRACT FROM AUTHOR]

The microbiological and hygienic quality of cow's, goat's and sheep's milk in the Czech Republic was evaluated. Milk (230 samples) was collected on 41 farms and investigated from May 2012 to October 2014. Milk was analysed for the presence of selected groups and types of bacteria: mesophilic microorganisms (total plate count - TPC), enterococci, Enterobacteriaceae, Escherichia coli, Staphylococcus aureus, Salmonella spp., Campylobacter spp., and Listeria monocytogenes. Besides these indicators and pathogenic agents, somatic cell count was determined as one of the indicators of mammary gland health in cows. TPC ranged between 8.3 ? 10² and 1.2 ? 109 CFU/ml and somatic cells between 1.6 ? 104 and 6.8 ? 106 cells/ml. The presence of E. coli was confirmed in 86.3% of samples and the colony counts ranged from 1.0 ? 10¹ to 4.0 ? 106 CFU/ml. The presence of verotoxigenic E. coli was confirmed in 3 samples (1.3%) (cow's milk 0%; goat's milk 6.3%; sheep's milk 4.4%). The presence of S. aureus was confirmed in 29.1% of the samples (cow's milk 26.9%; goat's milk 34.4%; sheep's milk 39.1%), but the numbers were very low (< 5.0 ? 10² CFU/ ml). L. monocytogenes was confirmed in 3 examined samples (1.3%) (cow's milk 0.6%; goat's milk 3.1%; sheep's milk 4.4%). Salmonella spp. and Campylobacter spp. were not detected in any of the samples tested. [ABSTRACT FROM AUTHOR]