Abstract
Escherichia coli infection is of high significance in chicken, especially in broilers. It produces lesions such as air sacculitis,
peritonitis, peri-hepatitis, pericarditis, osteomyelitis, synovitis and/or omphalitis. The present study was conducted E. coli
infected broiler chickens from field in and around Faisalabad. The main objective of the study was to detect different
pathogenicity genes (fimC, tsh, iucD, papC, fyuA, irp2) of E. coli and associated lesions in broilers. The birds showing
suspected postmortem findings for E. coli were further investigated for histopathological studies and culture isolation. The
observations revealed that E.Coli infection was found in 84% of open house farm and 16% controlled houses farms. The
genes detected at higher prevalence were fimC having 92% prevalence, followed by tsh 80%, iucD 72%, fyuA 60%, papC 48%
and irp2 32%, respectively. A total of 17 strains were identified on the basis of presence or absence of these six genes. These
results also indicate the involvement of certain genes more than others in producing severe changes in different body tissues
as in more than 50% cases, the genes including fimC, tsh and iucD were detected.
