Escherichia coli Infection in Poultry

Abstract

SUMMARY The serological examination of 797 E. coli strains isolated from cases of “coli-septicaemia” (243 strains) and other avian diseases is reported. Over 60 per cent of the strains from “coli-septicaemia” belonged to the serological O groups, O2, O78 or O1. The E. coli strains isolated from other avian diseases showed less serological uniformity, although over 18 per cent belonged to the O2 group. The results of pathogenicity tests using the common avian serotypes are described, and a syndrome resembling naturally occurring “coli-septicaemia” was reproduced by the intravenous inoculation of the E. coli serotypes most commonly isolated from field cases. The results of in vitro sensitivity tests showed that all E. coli strains tested were sensitive to furazolidone and that the incidence of tetracyclinc-resistant strains isolated from field outbreaks of disease had increased over the past 4 years. A small therapeutic trial in experimentally infected birds demonstrated the efficacy of furazolidone.