Detection of Extended-spectrum beta-lactamase and AmpC beta-lactamase Producing Escherichia coli Isolates from Chickens

The aim of this study was to investigate the presence of Extended-spectrum beta-lactamase (ESBL) and AmpC beta-lactamase producing Escherichia coli strains isolated from meat and faecal samples of chicken. Faecal samples (n: 384) were collected from broiler and egg-type healthy chickens in 43 flocks and 384 fresh chicken meat samples from local markets, supermarkets and slaughterhouses. E. coli isolates were tested phenotypically according to the guidelines of CLSI (2013) for ESBL production. Phenotypic detection of AmpC production was carried out by determination of resistance to cefoxitin and susceptibility to cefepime. Also, presence of genes encoding different types of beta-lactamases (bla(CTX-) (M), bla(TEM), bla(SHV) and the mutation in the promoter of AmpC) in all phenotypically ESBL or AmpC producing E. coli was investigated by PCR assays. In this study, bla(CTX-M) (95.4%), bla(CTX-M-1) (81.8%), bla(CTX-M-8) (4.5%), bla(TEM) (45.4%) and bla(SHV) (2.2%) genes were detected from faecal samples and blaC(TX-M) (100%), bla(CTX-M-1) (28.5%) and bla(TEM) (7.1%) from meat samples. The only plasmidic AmpC beta-lactamase found was the CIT type.