Detection of the eaeA Gene in Escherichia coli Isolated from Broiler Chickens by Polymerase Chain Reaction

The aim of this study was to isolate Escherichia coli from chickens and to determine the presence of the eaeA gene, a virulence factor detected in Escherichia coli, in the isolates by polymerase chain reaction (PCR). Different chicken organs (lung, liver and spleen) were inoculated onto blood agar and biochemical tests were performed on the suspicious isolates. Escherichia coli was isolated from 67.5% (81/120) of the samples. DNA was extracted from these isolates and was amplified by PCR, using a pair of primers derived from the eaeA (virulence) gene. In the agarose gel examination of PCR products, 48.1% (39/81) of the iso-lates were determined to have this virulence factor. Correct amplification with a molecular length of 384 bp was obtained in the analysis of all the isolates by species-specific PCR, which confirmed the results of the detection of the eaeA gene in Escherichia coli. The eaeA gene, which is mainly responsible for the viru-lence of Escherichia coli, is commonly present in Escherichia coli strains isolated from this region and the significance of this situation for animal and public health was discussed.