Project Summary
Bacterial coldwater disease (BCWD), caused by Flavobacterium psychrophilum, is one of the most important diseases leading to losses of farmed rainbow trout (Oncorhynchus mykiss), an industry valued at more than $200M. The disease has led to significant economic losses, accounting for 70% of total mortalities. Typically, BCWD-infected fish would be treated with antibiotics, but this raises issues due to antibiotic resistance and stringent regulatory controls on antibiotic treatments. To counter these losses, new technologies to prevent disease, including vaccines, are necessary to reduce costs to farmers and continue to grow the industry. There are currently no commercially approved vaccines to prevent BCWD in the U.S. Medgene intends to develop a novel subunit vaccine that can be incorporated into the fishes’ feed. By utilizing our innovative vaccine-development platform to rapidly produce vaccine products for changing and emerging diseases, we can quickly produce vaccines against BCWD for implementation in fish trials. This project specifically targets the NCRAC Research Priority “Theme B: Fish Health Sessions – 1. Disease Management & Medication Use – b. Bacterial Coldwater Disease.” With the development of a stable, safe, and effective vaccine for trout feed, Medgene has the potential to significantly decrease economic losses for the trout farmer.
Objectives
Objective 1: Develop a novel subunit vaccine against the BCWD pathogen F. psychrophilum. To achieve this objective, Medgene will develop multiple vaccine constructs encoding full-length proteins for use as subunit antigens in a multivalent vaccine. The proteins will be produced by our scalable recombinant bacterial platform and adjuvanted with the Montanide GR 01 adjuvant for oral administration via coated fish feed.
Objective 2: Assess the serological response to the BCWD vaccine in vaccinated fish by serological assay. To provide initial in vivo validation of the proposed BCWD vaccine, Medgene will evaluate the serum from vaccinated fish. Two feeding regimens with four dose levels for the BCWD vaccine will be evaluated, and the serological response to vaccination will be assessed.
Objective 3: Assess the efficacy of the BCWD vaccine at preventing disease in F. psychrophilum-challenged rainbow trout. To achieve this objective, Medgene will perform a challenge experiment in rainbow trout vaccinated with the proposed BCWD vaccine. Fish will be vaccinated at the dose level determined most effective in Objective 2 and exposed to the pathogen to assess the ability of the vaccine to confer immunological protection against BCWD.
Duration: 1 Year (January 1, 2026-December 31, 2026)
Participants
PI: Casey Wright, Ph.D., Medgene
Co-PI: Luke Oliver, Ph.D., University of Idaho
Extension Liaison: Myron Kebus, D.V.M., Michigan State University
Industry Liaison: Luke Fredrickson, Houdek
Project Outline
Award Amount
$148,387
Award Number
2022-38500-38103, $23,099
2023-38500-40773, $18,911
2024-38500-42307, $106,377
