Immunogenicity of pressure inactivated Edwardsiella tarda bacterin to Anguilla japonica (Japanese eel).
Japanese eel Anguilla japonica were immunized with inactivated Edwardsiella tarda bacterin preparations (formalin-killed cells, FKC (0.4%), formalin with heat-killed cells, FHKC (0.1% and 70 degreesC for 10 min), heat-killed cells, HKC (70 degrees C for 15 min), potassium chloride-killed cells, KKC (0.6%), tannic acid-killed cells, TKC (0.9%), citric acid-killed cells, CAKC (0.9%), pressure-killed cells, PKC (600 psi for 5 min) and electric current-killed cells, ECKC (100 mA at 12 v DC for 5 sec) via intraperitoneal injection in order to develop adequate inactivating method. Immune parameters in the immunized eel were measured to compare responses to different bacterins. Generally, eel rose agglutinating antibody titer in the serum within 2 week and the maximum titer occurred at 6 weeks post immunization. Elevated and significantly higher titer was produced with the PKC of E. tarda than other bacterin preparations. An Enzyme Linked Immunosorbent Assay (ELISA), to determine specific anti-E. tarda antibody in the serum, also showed significantly higher antibody titer with PKC than the other antigen preparations. Bacteriostatic assay with serum and live E. tarda indicated significantly higher activity in the PKC-immunized fish. Immunization with PKC also showed the increased level ofphagocytosis. PKC-inactivated vaccine at an immunization dose of 10(6) cells/fish induced high protection against experimental infection. Coincident with higher immune parameters and protection in the fish immunized with the PKC bacterin strongly suggested that pressure-killing is an effective inactivating method to develop an effective vaccine against edwardsiellosis.
Department of Fisheries and Marine Bioscience, Jessore Science and Technology University, Jessore, Bangladesh, Japan.
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Hossain
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Kawai
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Oshima
D000811:Anguilla / Q000276:immunology* / Q000382:microbiology*; D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology; D000917:Antibody Formation; D001426:Bacterial Proteins / Q000276:immunology; D020609:Edwardsiella tarda / Q000276:immunology* / Q000472:pathogenicity; D005393:Fish Diseases / Q000276:immunology* / Q000382:microbiology*; D007114:Immunization; D008264:Macrophages / Q000166:cytology / Q000378:metabolism; D010587:Phagocytosis; D015996:Survival Rate; D014611:Vaccination / Q000379:methods; D015164:Vaccines, Inactivated
D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D015164:Vaccines, Inactivated