The present study was designed to throw the light on isolation of Escherichia coli (E. coli) strains
accompanied by Infectious bronchitis virus (IBV). Classification and serotyping of bacterial isolates
of E.coli were done followed by their antimicrobial susceptibility testing, also isolation and
identification of IBV was done. For that purpose, a total of 200 organs, swap and samples were
aseptically collected from broilers and layers flocks suffered from respiratory symptoms and
general illness from both private and governmental farms during the period from 2015 till the end of
2017. Results revealed that the prevalence of E. coli was 67.5% and IBV was 61.5% in the collected
samples. The serological identification showed that the most predominant serotype for E. coli was
O 158 and there was a high level of resistance of isolated strains against doxycycline and
tetracycline.