Detection of Edwardsiella tarda from fish by the specific amplification of a 450 bp fragment of 168 rRNA gene and its sequencing

Species-specific primers were developed to detect the 16S ribosomal RNA gene of Edwardsiella tarda. The region of 16S rRNA gene 450 bp was amplified in all 16 isolates of E. tarda. Amplification, which resulted -in detectable levels of PCR product, was achieved when a minimum of 8 CFU/ml of E. tarda. The detection limit for 165 rRNA gene by PCR amplification ofgenomic DNAwas 20 pg. There was no cross reactivity found with Escherichia coli, Salmonella arizonae, Pseudomonas alcaligenes, Aeromonas hydrophila, Vibrio cholerae, Staphylococcus aureus and Flavobacterium spp.Â