Antimicrobial Resistance of Escherichia coli Isolated from Chickens with Colibacillosis

In order to asses susceptibility of Escherichia coli to seven antimicrobial drugs, we tested one hundred Escherichia coli isolates, recovered from broilers with clinical signs and lesions of colibacillosis in the West area of Algeria. Serogrouping showed that 52% of the isolates belong to one of the serotypes O78, O2 and O1. Antibiograms revealed a high level of resistance to oxytetracycline, trimethoprim-sulfmethoxazole and enrofloxacin (87, 70 and 45%, respectively). A low percentage of strains were resistant to gentamycin and nitrofurane (3 and 2%, respectively). All strains were susceptible to ampicillin. 72% of the isolates were resistant to at least 2 antibiotic and 45% were resistant to at least 3 antibiotics.