title: The efficacy of five avirulent Edwardsiella tarda strains in a live vaccine against Edwardsiellosis in Japanese flounder, Paralichthys olivaceus.
abstract: We evaluated the tissue persistence and live vaccine efficacy of five avirulent Edwardsiella tarda strains (E22, SU100, SU117, SU138, and SU244) isolated from the Japanese eel (Anguilla japonica) and from the environment. The live vaccines, containing a single strain, were injected intraperitoneally into Japanese flounder (Paralichthys olivaceus). Viable bacteria from all the strains (excluding SU100) were recovered from trunk-kidney tissue 28 d post-injection. Japanese flounder inoculated with E22 had the highest relative percentage survival (RPS = 45%) in an artificial challenge with virulent E. tarda (NUF806). The serum of E22-vaccinated fish had a significantly higher agglutination titer against NUF806. In contrast, there was little or no increase in the agglutination titer of the fish that were inoculated with the remaining avirulent strains. Injection with avirulent E. tarda increased the expression of cytokine genes, including interleukin-1beta (IL-1beta), type 1 interferon (IFN), and IFN-gamma in head-kidney of the Japanese flounder.
authors.affiliation: Aquatic Animal Health Division, National Research Institute of Aquaculture, Fisheries Research Agency, Mie 516-0193, Japan. takanoto@fra.affrc.go.jp
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Takano
authors.forename: Tomomasa
authors.initials: T
authors.lastname: Matsuyama
authors.forename: Norihisa
authors.initials: N
authors.lastname: Oseko
authors.forename: Takamitsu
authors.initials: T
authors.lastname: Sakai
authors.forename: Takashi
authors.initials: T
authors.lastname: Kamaishi
authors.forename: Chihaya
authors.initials: C
authors.lastname: Nakayasu
authors.forename: Motohiko
authors.initials: M
authors.lastname: Sano
authors.forename: Takaji
authors.initials: T
authors.lastname: Iida
mesh_terms: D000818:Animals; D058491:Bacterial Load; D001428:Bacterial Vaccines / Q000276:immunology*; D002470:Cell Survival; D002478:Cells, Cultured; D020609:Edwardsiella tarda / Q000472:pathogenicity*; D004756:Enterobacteriaceae Infections / Q000276:immunology / Q000401:mortality / Q000517:prevention & control / Q000662:veterinary*; D005393:Fish Diseases / Q000276:immunology / Q000382:microbiology / Q000401:mortality / Q000517:prevention & control*; D005432:Flounder; D010586:Phagocytes / Q000166:cytology / Q000382:microbiology
chemical_list: D001428:Bacterial Vaccines