Synchrosmolt: Smolt production protocols and breeding strategies for synchronized smoltification

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 forseawater 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. The dataset includes RNA-seq of gill tissue from 2,805 smolts sampled before their transfer to seawater, as well as whole genome sequencing (WGS) of the 112 parents for genotyping purposes.