Efficacy of injection vaccines against Flavobacterium psychrophilum in rainbow trout, Oncorhynchus mykiss (Walbaum)

Abstract

Efficacy of mineral oil-based experimental injection vaccines against Flavobacterium psychrophilum were tested in rainbow trout, Oncorhynchus mykiss (Walbaum), under laboratory and field conditions. The vaccines consisted of formalin- or heat-inactivated whole bacterium cell preparations of two different serotypes (Fd and Th) or a combination of serologically different F. psychrophilum (Fd and/or Th and/or Fp(T);Th). Specific antibody responses against the bacterium in plasma and skin mucus were evaluated post-vaccination with enzyme-linked immunosorbent assay. Efficacy of the vaccinations was determined by challenge trials to F. psychrophilum with the vaccinated rainbow trout. Significantly higher antibody levels in plasma were detected in vaccinated fish compared with mock-vaccinated fish. Injection vaccination did not trigger specific antibody production in the skin mucus. Significantly higher survival of i.p. vaccinated fish compared with non-vaccinated fish was observed during the challenge. The results suggest that mineral oil-based injectable vaccines containing formalin- or heat-inactivated virulent cells of F. psychrophilum effectively triggered specific antibody production and protected the fish against bacterial cold water disease.

The effects of inactivation methods of Yersinia ruckeri on the efficacy of single dip vaccination in Atlantic salmon (Salmo salar)

“…However, no significant difference was found between these groups. The present results were consistent with the results for survival of vaccinated fish with heat‐inactivated Flavobacterium psychrophilum which was similar or higher compared with fish vaccinated with formalin‐inactivated antigens (Holt, ; LaFrentz et al., ; Madetoja et al., ; Rahman, Ototake, Iida, Yokomizo, & Nakanishi, ; Rahman et al., ; Rahman, Ototake, & Nakanishi, ). Using ammonium sulphate then heat to inactivate Y. ruckeri to produce vaccines may be more advantageous because the treatment does not cross‐link proteins and may increase the shelf‐life of the bacterin because the treatment also precipitates potentially damaging proteases (Farrell & Crosa, ).…”

Bacterial coldwater disease of fishes caused by Flavobacterium psychrophilum

“…Passive immune protection to F. psychrophilum with serum from convalescent, and previously immunized rainbow trout was demonstrated (in rainbow trout) by LaFrentz et al [97]. Protection to specific molecular mass F. psychrophilum cell fractions was shown by LaFrentz et al [36], also to the P18 surface antigen [98], and to formalin-and heat-inactivated F. psychrophilum cells [99]. Additionally, protection against F. psychrophilum was shown by vaccination with an outer membrane fraction [100] and a 70-100 kD cell fraction [36] composed of O-polysaccharide components of LPS.…”

Molecular characterization and expression pattern of c-type and g-type lysozyme isoforms in starry flounder Platichthys stellate infected with Streptococcus parauberis

“…In the present investigation, the administration of bacteria intraperitoneally allowed the pathogens immediate access to the circulation. Therefore, the infected fish displayed an immune response in the skin via alternative ways, that is, (1) one mechanism for plasma proteins to get into mucus is the direct expression of the proteins by the epidermis, or (2) circulating plasma proteins are passively transferred from the secondary circulatory system to the skin mucus during infection [48][49][50]. In the present species, the lysozyme activity level in mucus was consistently higher than that in serum, both in non-challenged and bacteria-challenged groups.…”