The cleanerfish lumpfish (Cyclopterus lumpus L.)- Immunity, diseases and health

Lumpfish is used as cleaner fish to remove lice from Atlantic salmon. As the supply of lumpfish is based strictly on farmed individuals, it is a sustainable, environmental friendly and gentle alternative to medical and mechanical treatment. In recent years, the demand for lumpfish has led to an increase in the production from around 0.4 million lumpfish in 2012 to 30 million in 2018. In parallel with increased used of cleaner-fish and the rapid increase in number of lumpfish produced, health-related challenges emerged. Large scale disease outbreaks among the lumpfish, caused by Pasteurella-like bacteria, Vibrio and atypical Aeromonas salmonicida affected fish-welfare and reduced the overall efficiency of the cleaner-fish strategy. In the current project, we have focused on immunity, infections and preventive health measures of lumpfish. The goals have been to expand our knowledge of how lumpfish respond upon infections and stimulations, and to develop vaccines protecting the lumpfish against its pathogens. Although progress regarding more efficient vaccines has been made, more work is needed to optimize and develop vaccines tailored for lumpfish. We have characterized immune cells and immune responses in lumpfish by doing RNA sequencing and whole transcriptome analyses as well as in-depth analyses of selected immune molecules. Furthermore, we have developed anaesthetic protocols for lumpfish, developed protocols for pharmacokinetic analyses of plasma and different tissues of lumpfish and evaluated the effect of different antibacterial treatment of lumpfish after experimental challenge with Vibrio anguillarum, atypical Aeromonas salmonicida and Pasteurella sp. Also, we have done pathogenicity testing of different bacteria by used of an in vitro multi-well method. Our goal is that the results generated from the project will contribute to improve fish health and good ethical conditions both under production and during its use as cleaner-fish. The University of Bergen is the owner of the project. The collaborative partners are from the Norwegian Veterinary Institute, Institute of Marine Research, Computational Biology Unit (UiB), Norwegian Institute for water Research, Fjord Forsk Sogn AS, National institute of nutrition and seafood research, PHARMAQ AS, University of Stirling (UK) and University of Santiago de Compostela (Spain)

Vi har undersøkt immunceller og responser som er nyttig for komparative og anvendt forskning. Vi har etablert reprodusere smittemodeller som er viktig for å teste effekt av vaksinering og antibakteriell behandling. Bakterienes patogenisitet er undersøkt ved smitte av larver. Metoden muliggjør screening av et stor antall bakterier uten å måtte gjøre kostbare fiskeforsøk. Vi har beskrevet kliniske tegn hos syk rognkjeks, samt screenet patogene bakteriers sensitivitet overfor antibakterielle midler. Vi har undersøkt effekten av bedøvelsesmiddel. Vår erfaring er at det ikke er nødvendig å bedøve rognkjeks ved lettere håndteringer. Vi har undersøkt effekt av ulike antibakterielle midler, samt gjort farmakokinetiske analyser. Riktig behandling er nødvendig for å unngå fremvekst av resistente bakterier. Resultater våre bidrar til bedre helse og velferd for rognkjeksen. Frisk og robust fisk er en forutsetning for fremtidig bruk av rognkjeks som rensefisk i fiskeoppdrettsnæringen.

Cleaner-fish like lumpfish and wrasse have shown to be efficient tools in the fight against salmon lice and are chosen by many fish farmers as alternatives to medicinal treatment. Sea lice are one of the main health-related challenges to the aquaculture industry and increasing prevalence of resistance among lice to commonly used chemotherapeutics has stimulated commercial farming of lumpfish. In parallel with the huge increase in demand for cleaner-fish and the rapid increase in companies producing lumpfish over the last year, health-related challenges are now emerging. Large scale disease outbreaks among the lumpfish, caused by Pasteurella-like bacteria, Vibrio and atypical Aeromonas salmonicida have affected fish-welfare and reduced the overall efficiency of the cleaner-fish strategy. This situation clearly shows the need for immune prophylaxis like vaccination and/or immune stimulation of lumpfish. Immune prophylaxis stands out as the most important factor for improving fish health. In the proposed project we will focus on immunity, infections and preventive health of lumpfish. As we have experience with handling of lumpfish, immune cell isolation, cultivation of its pathogens and experiments of fish, the project builds on a solid foundation. The applicant will, in collaboration with national and international experts, characterize different subsets of immune cells and their responses upon bacteria encounter and immunostimulation, characterize pathogens and compare them with respect to virulence factors to identify the best vaccine candidate, test vaccines and develop a larval challenge model for pathogenicity testing (in accordance with the 3Rs) and develop protocols for anaesthesia and antibacterial treatment. This project will increase national collaboration and promote the internationalization of Norwegian research by international networks building and mobility. The proposal includes PI, 1 post doctor, 1 PhD (self-funded UiB) and master students.