title: Differentiation of field isolates of Pasteurella multocida serotype 3,4 from live vaccine strain by genotypic characterization.
abstract: Fifty-five serotype 3,4 isolates of Pasteurella multocida, isolated from turkeys dead from fowl cholera, were characterized (fingerprinted) genotypically for comparison with the serotype 3,4 live fowl cholera vaccine principally used in turkeys in California. Twenty-three isolates were obtained from turkeys vaccinated with the M9 live vaccine, and 32 additional isolates were from turkeys not vaccinated for fowl cholera. Methods of characterization included restriction endonuclease analysis of chromosomal DNA and ribotyping, a technique for highlighting restriction site heterogeneity of highly conserved ribosomal RNA genes and associated sequences using a radiolabeled rRNA probe. Eight different genotypes or ribotypes were detected in these isolates by the above methods. Of 23 isolates from M9-vaccinated turkeys flocks, 19 were the same ribotype as M9. Thirty of 32 isolates recovered from unvaccinated turkeys were different ribotypes from M9. The remaining two isolates resembled M9 and were recovered from two different flocks placed in succession on a turkey farm where a flock placed previously had been vaccinated with M9, suggesting interflock transmission. Ribotyping and restriction endonuclease analysis appear to be useful tools to aid in the determination of the role that the live vaccine plays in fowl cholera epidemiology.
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Veterinary Medicine, University of California, Davis 95616.
authors.forename: K P
authors.initials: KP
authors.lastname: Snipes
authors.forename: D C
authors.initials: DC
authors.lastname: Hirsh
authors.forename: R W
authors.initials: RW
authors.lastname: Kasten
authors.forename: T E
authors.initials: TE
authors.lastname: Carpenter
authors.forename: D W
authors.initials: DW
authors.lastname: Hird
authors.forename: R H
authors.initials: RH
authors.lastname: McCapes
mesh_terms: D000818:Animals; D001345:Autoradiography; D001428:Bacterial Vaccines / Q000235:genetics*; D015139:Blotting, Southern; D004269:DNA, Bacterial / Q000032:analysis; D004587:Electrophoresis, Agar Gel; D005838:Genotype; D010325:Pasteurella / Q000145:classification* / Q000235:genetics / Q000276:immunology; D010326:Pasteurella Infections / Q000382:microbiology / Q000662:veterinary*; D011201:Poultry Diseases / Q000382:microbiology*; D015347:RNA Probes; D012335:RNA, Ribosomal / Q000235:genetics; D015183:Restriction Mapping; D012703:Serotyping; D014422:Turkeys / Q000382:microbiology*
chemical_list: D001428:Bacterial Vaccines; D004269:DNA, Bacterial; D015347:RNA Probes; D012335:RNA, Ribosomal