Studies on enterohaemorrhagic Escherichia coli (EHCE)‎ strains non O 157 : H 7 in chicken with regard to antibiotic resistance gene on plasmid

الملخص EN

Shiga-toxin-producing Escherichia coli (STEC) are the most important recently emerged group of food-borne pathogens.

Among fifty EHEC strains, thirty strains were found as non O157 EHEC (60 %) by serotyping.

Also the highest incidence of O26 and O111 were 16% and 14 %, respectively, meanwhile the lowest was of O128 (2 %).

Antibiotic resistance profiles for these strains showed 100 % resistance to: sulfamethoxazole, Trimethoprime, chlormphencal, colistin, gentamycin and tetracycline.

However, they showed 85% resistance to streptomycin and doxycycline, 80% resistance to cefotraxone while their resistance for amoxicillin clavulanic acid was 75 %.

PCR examination for twenty strains of EHEC non O157 revealed stx1 gene in 45 %, stx2 in 65% while hly in 80 % of the examined strains.

Antimicrobial resistance genes for these strains confirmed that sulI, aadA and blaTEM resistance genes were detected in percentages of 85%, 75 % and 60 %, respectively.

Recommendation for minimizing an excessive use of antibiotics in the veterinary field and periodically use of different antibiotics could overcome the problem of increased bacterial resistance.