title: Comparative evaluation of a bivalent killed Salmonella vaccine to prevent egg contamination with Salmonella enterica serovars Enteritidis, Typhimurium, and Gallinarum biovar Pullorum, using 4 different challenge models.
abstract: We evaluated a newly developed commercial bivalent killed Salmonella vaccine Oilvax SET for its ability to decrease contamination with Salmonella enterica serovars Enteritidis and Typhimurium in layer chickens. In either an oral or intravaginal challenge model, the fecal shedding was decreased in vaccinated hens, but egg contamination was not evaluated due to scarcity of contaminated eggs even in the unvaccinated control groups. In contrast, an intravenous and an intraperitoneal challenge resulted in the relatively high level of egg contamination in unvaccinated chickens, which was significantly reduced in vaccinated chickens. In a second experiment, 2 strains of Salmonella serovar Gallinarum biovar Pullorum, which has the common O9 antigen with SE and transmits vertically into eggs, were used to test the efficacy of the Oilvax SET against egg transmission. Vertical egg transmission by the Pullorum strain was significantly reduced in the vaccinated groups of hens. The Oilvax SET can be a useful tool in the control of Salmonella egg contamination in laying hens.
authors.affiliation: Laboratory of Zoonoses, School of Veterinary Medicine and Animal Sciences, Kitasato University, Towada, Aomori 034-8628, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Okamura
authors.forename: Hajime
authors.initials: H
authors.lastname: Tachizaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Kubo
authors.forename: Shuichi
authors.initials: S
authors.lastname: Kikuchi
authors.forename: Akiko
authors.initials: A
authors.lastname: Suzuki
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Takehara
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nakamura
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis / Q000096:biosynthesis; D002645:Chickens / Q000276:immunology*; D004531:Eggs / Q000382:microbiology*; D005243:Feces / Q000382:microbiology; D005260:Female; D005506:Food Contamination / Q000517:prevention & control*; D006801:Humans; D011201:Poultry Diseases / Q000276:immunology* / Q000517:prevention & control*; D012481:Salmonella Infections, Animal / Q000276:immunology / Q000517:prevention & control*; D022562:Salmonella Vaccines / Q000276:immunology*; D019779:Salmonella enterica / Q000276:immunology*; D012477:Salmonella enteritidis / Q000276:immunology*; D012486:Salmonella typhimurium / Q000276:immunology*; D015164:Vaccines, Inactivated / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D022562:Salmonella Vaccines; D015164:Vaccines, Inactivated