INCIDENCE OF PATHOGENIC ESCHESICHIA COLI IN SOME POULTRY SPECIES IN EGYPT AND ITS EFFECT ON CHICKENS PERFORMANCE

The highest incidence of positive pathogenic E.COLI (APEC) isolated in this study was from chickens (57.96%) followed by ducks ,pigon, turkey ,ibis and quail with a percentage ,25.48%, 5.10%, 4.46%, 3.82% and 3.18% respectively. Heart , liver and lungs were the important tissues in production of APEC E.COLI O26 , O127, O55, O119, O111, O78, O86, O2 and O114 were the most prevalent serogroups identified in this study .using PCR five virulance associated genes in the APEC serogroups were irp2 , iron, ompt, iss and hlyf from all examined isolates . xperimental infection of broiler chickens with the different isolated E.coli serogroups ,o78 and o2 showed the highest mortality rates 60% and 50% respectively  with   severe reduction in the mean body weight from 20-30% . Antibiotic sensitivity of the isolated APEC was studied.