title: Characterization of Escherichia coli isolated from cases of avian colibacillosis.
abstract: Forty-four western Canadian isolates of Escherichia coli associated with colibacillosis of turkeys and chickens were examined for serotype, antibiotic resistance, and production of aerobactin. The isolates belonged to fourteen O serogroups, with 39% of the strains being non-typeable. A high frequency of resistance to tetracycline, kanamycin, neomycin, cephalothin, streptomycin and erythromycin was observed. Most isolates produced aerobactin. Ten E. coli belonging to serogroups O1, O2 and O78 were also examined for pili production, hemagglutination, serum sensitivity, production of iron-regulated outer membrane proteins (IROMPS), and virulence. All isolates examined produced pili, exhibited mannose-sensitive hemagglutination of avian red blood cells and produced IROMPS under iron-restricted growth conditions. The five isolates of serogroup O1 and O2 were resistant to killing by turkey serum and were highly virulent. Only two of the five isolates of serogroup O78 were serum resistant. No correlation between serum resistance and virulence was observed in serogroup O78.
authors.affiliation: Veterinary Infectious Disease Organization, Saskatoon, Sasatchewan.
authors.forename: B J
authors.initials: BJ
authors.lastname: Allan
authors.forename: J V
authors.initials: JV
authors.lastname: van den Hurk
authors.forename: A A
authors.initials: AA
authors.lastname: Potter
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis; D001770:Blood Bactericidal Activity; D002645:Chickens / Q000382:microbiology*; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000145:classification* / Q000187:drug effects / Q000472:pathogenicity / Q000502:physiology; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary*; D006877:Hydroxamic Acids / Q000378:metabolism; D011201:Poultry Diseases / Q000382:microbiology*; D012703:Serotyping / Q000662:veterinary; D017262:Siderophores / Q000096:biosynthesis; D014422:Turkeys / Q000382:microbiology*; D014774:Virulence
chemical_list: D000900:Anti-Bacterial Agents; D001425:Bacterial Outer Membrane Proteins; D006877:Hydroxamic Acids; D017262:Siderophores; C031819:aerobactin