KSP: SALMON BROODSTOCK CARRYING STERILTY TO THE NEXT GENERATION (SALSTER)

The primary objective of the SALSTER project is to explore and establish, biotechnological methods for industrial scale production of genetically sterile salmon, with the secondary aim being to conclude on the market potential of such biotechnological methods. Currently, Atlantic salmon is to a large extent cultivated in open sea cages with the associated risk of escape. Upon escape, farmed salmon can breed with wild populations, thereby affecting the genetic makeup of native populations. This effect is considered as the most negative, long-term environmental footprint of Atlantic salmon open-sea cage farming. This aspect recently gained even more relevance since wild salmon has been added to the red list of threatened species in Norway. Therefore, using sterile fish in commercial aquaculture operations is a sustainable green strategy to achieve biological containment of farmed salmon, and consequently protecting wild populations. The only method available to sterilize commercial-scale numbers of salmon is by triploidization. However, triploid salmon are generally more sensitive to suboptimal rearing environments making them prone to skeletal deformities, less tolerant to rising seawater temperature and do not present a sustainable solution for producers. In the present project, we propose to explore new possibilities for inducing sterility using gene editing. Using this technology we will further develop two methods which aims at large scale production of sterile fish that either lacks germ cells (VIRGIN salmon) or the ability to enter maturity (FOREVERYOUNG salmon). Use of such sterile solutions in production will protect wild strains of salmon, but in addition to this; these sterility methods prevent puberty, thereby avoiding substantial welfare problems, such as reduced growth, lower flesh quality and increased disease susceptibility. In addition, use of sterile fish safeguard Intellectual Property Rights (IPR) for breeding companies.

The primary objective of this project is to explore and establish, biotechnological methods for industrial scale production of genetically sterile salmon, with the secondary aim being to conclude on the market potential of such biotechnological methods. Currently, Atlantic salmon is to a large extent cultivated in open sea cages with the associated risk of escape. Upon escape, farmed Atlantic salmon may genetically introgress into wild populations, thereby affecting the genetic integrity of native populations also in terms of life history genetics. This effect is considered to be the most negative, long-term environmental footprint of Atlantic salmon open-sea cage farming. This aspect recently gained even more relevance now that wild salmon has been added to the red list of threatened species in Norway. Therefore, using sterile fish in commercial aquaculture operations is a sustainable strategy to achieve biological containment of farmed salmon. Currently, the only method available to sterilize commercial-scale numbers of salmon is by triploidization. However, triploid salmon are generally more sensitive to suboptimal rearing environments making them prone to skeletal deformities. Here we propose using two biotechnological approaches to produce sterile fish; (i) genetically sterile fish lacking germ cells in production fish (VIRGIN offspring), derived from genetically sterile but fertile broodstock (VIRGIN BS), or (ii) surrogate produced genetically sterile gametes, which results in 100% sterility in fish produced by these gametes (FOREVERYOUNG salmon). Significant benefits are associated with the proposed, new approaches in salmon. Both of these sterility methods prevent puberty, thereby avoiding significant welfare problems, such as reduced growth, lower flesh quality and increased disease susceptibility. For breeding companies sterile fish safeguard Intellectual Property Rights (IPR).