UK: Landcatch and its scientific partners have applied a technique known as genomic selection -a method of screening the DNA of individual fish - to identify those that are most resistant to sea lice infection, one of the biggest problems facing the aquaculture industry.
The company announced to the Aquaculture UK conference in Aviemore that several million selected eggs will be commercially available by December, in Landcatch’s next spawning, to improve the resistance of the next generation of Atlantic salmon.
Dr Alan Tinch, director of genetics at Landcatch, told delegates at the conference that the industry may never get to the stage where farmed salmon are completely resistant to sea lice, but this development is a major advance in tackling the issue.
He said: “We are excited to bring this advance in technology to market and to take a step forward in reducing the impact of sea lice on welfare and performance of salmon.”
The firm’s scientists have demonstrated that sea lice resistance is inherited and can be predicted using DNA markers. The latest advance shows that sea lice resistance is controlled by a handful of DNA regions with large effects, a hundred or so regions with small effects and thousands of regions with minimal effects.
The Landcatch team takes a small fin sample from each fish and use a recently-developed SNP chip to analyse more than 100,000 markers, known as single nucleotide polymorphisms (SNPs). These SNPs help scientists locate genes associated with disease and, subsequently, predict the sea lice resistance of individual fish to be used in breeding.
Dr Tinch added: “Salmon breeding takes a leap forward with the successful implementation of genomic selection for sea lice resistance. We now have a high resolution digital quality image of the genetic value of each of our broodstock and predict with high accuracy which males and females are the most resistant to sea lice.”
Collaborators in the project are the universities of Glasgow, Stirling and Edinburgh, (including The Roslin Institute and Edinburgh Genomics) and Affymetrix UK Ltd. The work was funded by the UK’s innovation agency, the Technology Strategy Board, and the Biotechnology and Biological Sciences Research Council.