A Scottish research consortium working in collaboration with the Scottish Aquaculture Innovation Centre (SAIC) has unveiled a new plan aimed at developing resistance to sea lice by using selective breeding.
The research, which also involves Hendrix Genetics and the Institute of Aquaculture at Stirling University, is being overseen by Dr. Smaragada Tsaididou and Prof. Ross Houstin at the Roslin Institute based at Edinburgh University.
Genetic data is being used to create a novel method for identifying salmon that display an enhanced natural resistance to sea lice. In the past selective breeding using genomic tools has usually been conducted by looking at thousands of DNA sequences, which can be a very expensive process. However, by using a new method called genotype imputation, the project has identified a lower cost model that would make the technique affordable for breeders and producers.
It uses a much smaller number of genetic markers to judge the resistance salmon have to the lice. Variations are looked for at specific positions in fish genes which show how they will respond to disease and parasites, which will then allow breeders to choose parent fish that display better resistance. The technique mirrors others that have already been successfully used in livestock breeding programmes, and the expectation is that the method would also prove effective in other aquaculture species such as tilapia and shrimp, as well as being a preventative method which could improve resistance to gill disease and other health traits. Prof. Houston, who chairs aquaculture genetics at the institute, said:
‘Sea lice is one of the costliest health-related problems for the global salmon industry and can have a wide-scale impact on salmon health and welfare. In this study we used low density genetic markers to predict the resistance of salmon to sea lice. This is potentially a more cost-efficient way of breeding salmon with improved resistance to parasites and other diseases, helping to improve animal welfare and production.’
Caroline Griffin, aquaculture innovation manager at SAIC, added:
‘Collaborative research projects are crucial for finding new methods for enhancing fish health and wellbeing, while also supporting the future sustainability of the industry. Sea lice continues to be a prominent challenge for the sector worldwide and developing cost-effective, data-led techniques for future breeding could transform the ways in which we manage and treat sea lice on fish farms.’