Background for the project

With decreasing wildlife fisheries resources the aquaculture production today is subject to major expansion. Here efficient prophylaxis against infectious diseases is a prerequisite for an environmentally sustainable industry. The long and relatively protected coastline of Denmark gives ideal conditions for sea-rearing of rainbow trout and it is expected that the current production at approx. 8000 metric ton per year can be increased by a factor five within the next 5 years. However, despite intensive use of commercially available vaccines against bacterial infections, the mortality and use of antibiotics has remained unacceptably high.

 

New research from an expiring project has revealed, that the currently used vaccines provide insufficient protection against Danish pathogen variants and also that the vaccination implies some unacceptable side effects. Hence, the present project aims at developing and implementing tailor-made vaccines against Danish variants of the major bacterial pathogen in the marine trout farming, Aeromonas salmonicida (A.s.).

 

Also, emphasis will be on developing a complete vaccination program by which optimal disease prophylaxis against important bacterial infection throughout the lifetime of the fish can be obtained. In depth understanding of protective immunity will be pursued. New A.s. vaccine candidates will comprise autogenous antigens (autovaccine).

 

Vaccine delivery by bath and/or oral administration in combination with feed immunostimulants will be pursued for vaccination of small fish while injection vaccination of larger fish will comprise testing of new adjuvants and as well as rearing under specific pathogen free conditions up to vaccination. The project will combine research and development at all levels from molecular immunology analysis to vaccine testing under field conditions.

 

The project work will be organized into 7 workpackages (WPs)

  • WP1 Project management
  • WP2 Development of an experimental autogenous vaccine for injection
  • WP3 Characterization of protective immune mechanisms
  • WP4 Epidemiology of Aeromonas salmonicida
  • WP5 Determination of optimal vaccination strategies under laboratory conditions
  • WP6 Vaccine testing and optimizing under field conditions
  • WP7 Project synthesis, dissemination and training