RESEARCH - Research Summary

Animal Production Theme

Research Summary

Atlantic cod (Gadus morhua) and haddock (Melangrammus aeglefinus) are two promising marine finfish species for aquaculture in Atlantic Canada, as both of these species are prime white flesh fish that demand a high market price and have established markets in North America and Europe. Ongoing collaborative efforts between aquaculture companies in Atlantic Canada, and government (Fisheries and Oceans Canada, Institute for Marine Biosciences, National Research Council) and university researchers have provided valuable data that can be used to directly enhance the commercial production of both of these species. However, most of these studies do not directly address fish welfare issues with respect to the environmental conditions that these fish face in cage culture, and their impact on growth, mortality and disease resistance. This is one of several AquaNet funded projects to improve aquaculture husbandry practices for new aquaculture species to support the diversification and success of Canada’s marine aquaculture industry.

In cage culture, the species under study face seasonal fluctuations in temperature and temperature extremes (<0 and up to ~16-18 degrees) which create stress in fish. The goal of this research project is to enhance fish growth and decrease disease-related losses at haddock and cod cage-culture sites in Atlantic Canada. The project has four components: 1) to determine how feeding frequency and diet composition can be optimized at the cage-sites when water temperatures are sub-optimal; 2) to develop species specific markers/molecular probes that can be used to determine the fish’s immunological status; 3) to use molecular probes and stress-indices to investigate how fish density within the cages, husbandry practices and cage-site temperatures relate to disease susceptibility/immune function; and 4) to perform laboratory and on-site experiments to test the effectiveness of immunostimulants at “boosting” immunity, and helping to prevent infection with pathogens/parasites of greatest concern to cod and haddock culture in Atlantic Canada (Nodavirus, Loma, Aeromonas, Vibrio).

Milestones achieved in the first year of this three year project include conducting feeding behaviour, growth measurement and swim-performance tests of cod, DNA sequencing of the primary immunological molecules from haddock and cod to pursue stress tests, measuring their effects on the immune system, and developing and refining effective immunostimulant protocols. To date, the project has led to a much better understanding of the stress responses of haddock and cod in relation to both husbandry and environmental conditions and the effectiveness of immunostimulants on parasite resistance.

Network Investigators

Kurt Gamperl, Ocean Sciences Centre, Memorial University of Newfoundland, St. John’s, NL
Brian Dixon, Department of Biology, University of Waterloo, Waterloo, ON
Duane Barker, Centre for Aquaculture and Seafood Development, Marine Institute of Memorial University of Newfoundland, St. John’s, NL
Joe Brown, Ocean Sciences Centre, Memorial University of Newfoundland, St. John’s, NL
Stewart Johnson, Institute for Marine Biosciences, National Research Council, Halifax, NS
Scott McKinley, Faculty of Agricultural Sciences, The University of British Columbia, Vancouver, BC
George Iwama, Institute for Marine Biosciences, National Research Council, Halifax, NS
Atef Mansour, Northwest Atlantic Fisheries Centre, Fisheries and Oceans Canada, St. John’s, NL