First detection of carbapenem resistance in Enterobacteriaceae isolates isolated from dairy cows' mastitis infection in Turkiye

With this study, carbapenem resistance genes were declared for the first time in Enterobacteriaceae isolates isolated from dairy cows' mastitis infection in Turkiye. In the bacteriological examination of 212 milk samples, 14 (6.60%) E. coli, three (1.41%) Klebsiella oxytoca, and two (0.94%) Klebsiella pneumonia were isolated. At least two E. coli isolates were found to be resistant to all of the antibiotics used in the antibiogram test. The highest resistance was found against cefotaxime and amoxicillin in K. oxytoca isolates. According to the results of PCR targeting blaCTX-M, blaTEM, and blaSHV genes, the blaCTX-M gene was detected in one K. oxytoca and four E. coli isolates, which were found ESBL positive. According to the results of PCR targeting carbapenem and colistin resistance genes, the IMP gene was detected in four E.coli, one K. oxytoca, and one K. pneumonia isolates. OXA-48-like gene was detected in two E. coli isolates. This two E. coli isolates were also IMP gene positive. While NDM gene was detected in two E. coli, KPC gene was detected in one E. coli isolate. One of the colistin resistance genes, mcr-1 was detected in two E.coli strains with PCR. This study showed that ESBL production and carbapenem resistance in Enterobacteriaceae family strains to become prevalent and increasing, especially among E. coli isolates. Furthermore, identification of multiple antibiotic resistance in the isolates indicated that antibiotic resistance also spread rapidly and increased.