Molecular identification and antibiotic susceptibility patterns of Escherichia coli isolates from sheep faeces samples

Conventional bacterial isolation and polymerase chain reaction (PCR) were used in the evaluation and detection of 100 commensal Escherichia coli isolates from sheep faeces. Additionally, antibiotic susceptibility patterns were determined in 50 selected E. coli isolates against 12 antibiotics by disk diffusion method. In the present study, the PCR test was found to be a highly specific and reliable method for the detection of E. coli. The obtained susceptibility patterns divided this population into 21 groups, from which three groups (I, III and IX) accounted for 44% of the isolates. In general, a high prevalence of resistance (100%) was observed against tylosin, vancomycin, penicillin and erythromycin. Low level resistance to tetracycline (8.3%) and gentamicin (6.25%) were found in the E. coli isolates tested. No resistance rate was observed among E. coli isolates for co-trimoxazole. Our results also exhibited multiple drug resistance in E. coli strains from sheep and underline the importance of sheep as reservoir of resistance genes which may transfer to human and other hosts. Furthermore, this exceptionally high level of resistance to antimicrobials might herald problems in the management of intra- and extra-intestinal infections caused by E. coli.