The emergence of multidrug resistant E. coli isolated from animal and animal products become the main wary of food safety and public health authorities worldwide. The present study was undertaken to recognize the most important serovars and the antimicrobial sensitivity patterns of E. coli isolated from animals and animal products. Results showed that out of the 300 examined samples (75 cows mastitic milk, 77 buffalo's mastitic milk, 40 cattle meat, 43 buffaloes meat and 65 chicken meat), 60 isolates (20 %) were confirmed as E. coli based on cultural characteristic and biochemical identification. These isolates were further identified serologically, the obtained isolates were categorized as O26:H11 (4/22, 18%), O91:H21 (3/22, 13.6%), O111:H2 (2/22, 9%), O146:H21 (2/22, 9%), O1:H7 (1/22, 4.5%), O55:H7 (1/22, 4.5%), O119:H6 (1/22, 4.5%), O121:H7 (1/22, 4.5%), O78 (2/22, 9%), O125: H21 (2/22, 9%), O128 : H2 (1/22, 4.5%), O159 (1/22, 4.5%), and O44:H18 (1/22, 4.5%). The isolates were further tested for antimicrobial resistance against 14 commercial antibiotics. The obtained results showed that the isolates were resistant to Erythromycin (22/22, 100٪), Streptomycin (21/22, 95.5٪), Nalidixic acid (17/22, 80٪), Clindamycin (14/22, 63.6٪) and Sulphamethozole (11/22, 50٪). Lower resistance rate was observed in case of Cephalothin (9/22, 40.9٪), Tetracycline (7/22, 31.8٪), Ampicillin (6/22, 27.3٪), Colistin (5/22, 22.7٪), Ciprofloxacin (5/22, 22.7٪), Amikacin (4/22, 18.2٪), Levofloxacin (2/22, 9.1٪), Gentamycin (2/22, 9.1٪) and Meropenem was (1/22, 4.5٪). In conclusion, there a wide variation in E. coli serogroups isolated from different animals and animal products. These serogroups exhibited a high multidrug resistance index against the commonly used antibiotics. Therefore, regular monitoring of the potential sources of human infection with E. coli will help establish accurate preventive and curative measures.

The aim of the current study was to characterize E. coli isolates belonging to several serotypes in samples from different animal sources. The genetic diversity among the isolates was evaluated by multiplex PCR. Out of 30 suspected isolated E. coli which were identified microscopically, culturally and biochemically examined by VITEK2 and serologically identified there were 8 isolates showing low discrimination for E. coli and were non-typeable while 22 isolates positive, showing excellent level of identification for E. coli and were identified serologically. Thirteen different serogroups were identified, O26:H11, O91:H21, O78, O111:H2, O125:H21, O146:H21, O1:H7, O44:H18, O55:H7, O119:H6, O121:H7, O128:H2 and O159. Findings of multiplex PCR of virulence genes showed that the eaeA gene was successfully amplified in O26:H11; stx1 gene was successfully amplified in O26:H11, O55:H7, O91:H21, O111:H2, O119:H6, O128:H2 and O146:H21 serogroups but stx2 gene was successfully amplified in O1:H7, O26:H11, O78, O91:H21, O111:H2, O119:H6 and O125:H21. O91:H21, O111:H2 and O119:H6 serogroups carried both (stx1 and stx 2) genes, O26:H11 serogroup carried (stx 1, stx 2 and eae) genes and O44:H18, O121:H7 and O159 serogroups were negative for these genes. Findings of multiplex PCR of β-lactamase antimicrobial resistance genes showed that blaOXA gene was successfully amplified in O26:H11 only; blaCTX-M1 gene was successfully amplified in O78 and O121:H7 serogroups but blaTEM gene was successfully amplified in O26:H11, O91:H21, O111:H2 and O125: H21. O26:H11 serogroup carried both (blaOXA and blaTEM) genes and O1: H7, O44:H18, O55:H7, O119:H6, O128:H2, O146:H21 and O159 serogroups were negative for (blaOXA, blaCTX-M and blaTEM) genes. In conclusion, animals and animal products could be a significant reservoir of diverse E. coli virulence and antimicrobial resistance genes which is potentially hazardous to public health.