studies on the bffect of e. coli endotoxin in inducing colisepticaemia in chickens

) E. coli serogroups 01, 02, 08 and 078 were iso- lated :from chd.c kens suspected to be infected””with coli-septicaemia. col serogrop 078 was the most-:isolated predominant strain (51.8%). 2) !. coli serogroups 01, 042 and 053 were isoJ.’O).-t9d:from the intestinal contents of apparently heal tihy chickens” 3) Di:f:ferent degrees o:f cytopathic e:ffects depend-ing on the serogroups were produced in chicken embryo :fibro- blast cell culture with endotoxins~bacterial cells and cell free filtrates which extracted from ~4 coli strainsisolated from diseased chickens.4) No cytopatllic e:ffect was produced with endotoxin, bacterial cell, and cell :free :filtrate extracted from !.strains isolated :from apparently healthy Chickens.5)E. coli serogroups 02, 08 and 078 isolated fromdiseased chickens were pathogenic to 1 day old chicks.While E.£21! serogroup 01 was non pathogenic.serogroup 078was the most pathogenic strain and there was variation inthe pathogenicity within the same serogroup.