Features Research
Update – lice resistance

Professor Frank Nilsen, of the Department of Biology at the University of Bergen and head of one of Norway’s Centres for Research-based Innovation (CRI), recently confirmed that scientists are closing in on identifying the genes that would allow selective breeding of Atlantic salmon resistant to sea lice.

         In order to zero in on the salmon genes that regulate the individual fish’s resistance to sea lice, the centre has been receiving salmon from different “families” or strains bred by the Norwegian aquaculture firm AquaGen.

         Nilsen acknowledged that the company has been greatly assisted in selecting the fish by the development of a high-density “snp chip” that aids in picking out fish whose genes indicate high natural vulnerability or resistance to sea lice.

Several so-called “crossing” experiments have been carried out on laboratory-bred strains of lice with known resistance characteristics, and historical material from more than 180 sea lice specimens continue to be reviewed at the centre and other research institutes.

This process will lead to the selection of Atlantic salmon strains that have shown resistance to the invasive parasites in laboratory experiments. (Researchers in various parts of the world have confirmed that resistance (and susceptibility) to lice infection is passed on genetically in Atlantic salmon.)

         He also said that although the program is working with dozens of strains of Atlantic salmon, it’s only working with about eight different strains of lice.

– Quentin Dodd