Conceptual framework for how optimizing light regimes and genetics can improve synchronization of smolt development

In the project 'Smolt production protocols and breeding strategies for synchronized smoltification' researchers from NMBU, UiT, and NOFIMA are digging into the molecular biology and genetics of the smoltification process in Atlantic salmon.



Norwegian salmon farming is facing several challenges, one of which is a ~12-14% loss after seawater transfer. Numerous factors are responsible for this loss, but smolt quality and susceptibility to pathogen infection seem to be major contributing factors. This emphasizes that too many fish transferred to seawater in Norwegian salmon farms are not ‘optimal smolts’ suited for seawater transfer. This project will focus on two major factors contributing to this issue; the rearing protocols used for smolt production and the genetic contribution to variation in the response of fish to these rearing protocols. We believe that the interaction between these factors cause variation in smolt fitness in seawater and in turn to smolt losses. To improve smolt robustness, it is necessary to (i) develop new and better markers for predicting seawater performance and to (ii) produce smolts of both higher and more uniform seawater adaptability; i.e. higher survival and growth and less welfare issues. This project will address these key challenges by exploring optimization of smolt production protocols, validating novel markers for smolt ‘seawater readiness’, and study the possibilities to perform selective breeding for more uniform and ‘synchronized’ smolt development.


The main objectve of the “SynchroSmolt” project is to deliver improved smolt production protocols, monitoring tools, and enhanced broodstock to produce robust smolts with improved growth rates, survival, and welfare after sea transfer.

 In a nutshell the project will:

  • Evaluate light regimes on smolt development and performance in sea for individual fish
  • Identify genetic variation associated with smolt development and subsequent sea performance
  • Validate novel molecular markers for ‘smolt status’ in fresh water predictive for seawater performance