Breeding for extended temperature tolerance

Offentlig prosjektsammendrag

Growth rate and the time fish spend in seawater are among the most important factors for the economy of an Atlantic salmon farmer, and also affect the risks of problems with diseases and loss of fish. Temperature is a key parameter for growth and welfare in salmon farming. Salmon sea cage farms along the Norwegian coast from Rogaland to Finnmark have periods of very cold seawater and/or periods of very warm seawater. However, climate changes are affecting where the optimal temperatures for producing salmon in sea cages are, and sites that used to be very good on the west coast of Norway and Scotland now have periods with too high temperatures. Areas in northern Norway, Iceland, Canada and Russia that used to be on the cold side for farming salmon now have increased temperatures, and salmon farming is being explored in these areas. Also, farming of Atlantic salmon is spreading geographically to regions outside the natural biological optimum for salmon, and countries in southern Europe and Asia are experimenting with salmon farming. Finally, land-based farming of salmon during parts or all of the production cycle is becoming more common. This opens for better control of temperature in critical times, but also for the temptation of increasing the rearing temperature towards the upper limit in part of the production. The present project seeks to determine if it is possible to genetically select salmon with different temperature optima.