Enhanced efficacy of an attenuated Flavobacterium psychrophilum strain cultured under iron-limited conditions

Systemic and mucosal immune response of rainbow trout to immunization with an attenuated Flavobacterium psychrophilum vaccine strain by different routes

“…In the present study, IP immunization alone resulted in significant IgM production in serum and in gill and skin mucus while other routes of immunization did not result in significant anti-F. psychrophilum IgM production. This is in contrast to previous studies [31,32,38] showing antibody production following immersion delivery. The reason for the lack of specific antibodies in fish following immersion or AI routes is unclear but could be related to dose delivered and the use of larger fish in this study.…”

“…The efficacy of this vaccine has been improved by growing the bacteria under iron limiting conditions and has recently been shown to provide significant protection against CWD in coho salmon [32]. A deeper understanding of the immune response of fish to F. psychrophilum especially at the mucosal surfaces, which is the natural route of infection is important for further fine tuning the efficacy of the CWD vaccine and for better health management of farmed salmonids.…”

Complete Genome Sequence of Flavobacterium psychrophilum Strain CSF259-93, Used To Select Rainbow Trout for Increased Genetic Resistance against Bacterial Cold Water Disease

“…Herein we report the complete genome sequence of F. psychrophilum strain CSF259-93 utilized in the National Center for Cool and Cold Water Aquaculture (NCCCWA) rainbow trout selective breeding program. The CSF259-93 strain has been used to derive a live attenuated vaccine (8, 9) and has been characterized biochemically and immunologically (10–16). The strain belongs to multilocus sequence type 10 (17).…”

Assessment of cross‐protection to heterologous strains of Flavobacterium psychrophilum following vaccination with a live‐attenuated coldwater disease immersion vaccine

“…A number of earlier studies have clearly elucidated the advantages and feasibility of developing and using a vaccine against BCWD (Fredriksen et al., ; Håstein, Gudding, & Evensen, ; LaFrentz, LaPatra, Call, & Cain, ; Madetoja et al., ). In recent years, a rifampicin resistant strain of F. psychrophilum (CSF259‐93‐B.17) has been developed as a live‐attenuated vaccine and optimized to provide cultured salmonids protection from BCWD (LaFrentz et al., ; Long et al., ; Sudheesh & Cain, ). Previous research has shown that immersion vaccination provides significant protection and is effective in Coho salmon and rainbow trout following laboratory challenge with the virulent parent strain CSF259‐93 (Long et al., ; Sudheesh & Cain, ).…”

“…In recent years, a rifampicin resistant strain of F. psychrophilum (CSF259‐93‐B.17) has been developed as a live‐attenuated vaccine and optimized to provide cultured salmonids protection from BCWD (LaFrentz et al., ; Long et al., ; Sudheesh & Cain, ). Previous research has shown that immersion vaccination provides significant protection and is effective in Coho salmon and rainbow trout following laboratory challenge with the virulent parent strain CSF259‐93 (Long et al., ; Sudheesh & Cain, ). Over the past decade, this vaccine has been further investigated and enhanced following production under iron limited conditions (designated B.17‐ILM), and optimized under a range of conditions (LaFrentz, LaPatra, Call, Wiens, & Cain, ; LaFrentz et al., ; Long et al., ; Makesh, Sudheesh, & Cain, ; Sudheesh & Cain, ; Sudheesh et al., ).…”