This study investigates the presence o virulence-associated genes and antimicrobial resistance (AMR) in Escherichia ergusonii isolates obtained rom ostrich chicks. A total o 287 isolates were recovered rom 106 ecal samples rom ostrich chicks suering rom diarrhea and subjected to molecular identication and biochemical characterization. E. ergusonii was detected in 10 samples (9.4 %) using two PCR-detection protocols. Notably, the isolates lacked various virulence genes commonly associated with pathogenic E. coli including elt, est, stx, eae, ehly, cdt, iss, iutA, iroN, hlyA, ompT, except or one isolate harboring the astA gene. Antimicrobial susceptibility testing revealed that all isolates were susceptible to ciprofoxacin, while high resistance was observed against amoxicillin clavulanate (AMC), trimethoprim-sulamethoxazole (SXT), and doxycycline (D). Moreover, eight isolates displayed multidrug resistance (MDR) and our exhibited resistance to 9–11 antimicrobials. The most requent resistance gene was sul2, which was present in all isolates; the other resistance genes detected consisted o int1 (4/10), int2 (3/10), blaCMY (2/10), and qnrS, blaTEM , bla CMY , bla CTX-M , and o each were detected only in one E. ergusonii Isolate. Plasmid replicon typing identied the presence o I1 (7/10), N (5/10), and Y (1/10). This study provides valuable insights into the virulence and antimicrobial resistance o E. ergusonii isolates rom ostrich chicks, highlighting the complexity o antimicrobial resistance mechanisms exhibited by these bacteria. Further research is essential to understand the transmission dynamics and clinical implications o these ndings in veterinary and public health settings

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