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HomeReducing waste and improving fish health: Infectious Salmon Anaemia-resistance research underway

Reducing waste and improving fish health: Infectious Salmon Anaemia-resistance research underway

Author: Rob Fletcher, The Fish Site
13 February 2018

A new project that aims to speed up the development of a strain of salmon with higher tolerance against the infectious salmon anaemia virus (ISAV) is underway in Norway.

Called iSABreed, the three-year, NOK 8 million (£720,000) project is jointly funded by SalmoBreed (a Benchmark Company) and the Norwegian Research Council and will use the latest genomic techniques in a bid to understand the key genes involved in boosting ISA-resistance.

“At SalmoBreed we’ve had a breeding programme focusing on improving ISA survival since 2001 and have managed to increase survival by 26 percent over the four generations that have been produced through the programme so far,” explains the genetics manager, Borghild Hillestad.

“However, we would like to increase the survival, as well as the phenotype quality and knowledge on ISA genetics,” she adds. “Due to low to moderate heritability of ISA survival, we think we need more specialised tools. Today, the genomic analysis shows that ISA resistance is a complex trait, with potential influence of many genes. For such a polymorphic trait, we want to make our breeding programme to target the most effective genes, so we can assure that we are speeding up the rate of genetic gain for ISA robustness”

SalmonBreed genetics manager, Borghild Hillestad

In order to improve the phenotype for ISA-resistance the initiative is going to involve a series of challenge tests.

“Two challenge tests are going to examine the survival and the viral loads on both vaccinated and unvaccinated salmon; the other challenge setups, will investigate the ‘shedder capacity’ of vaccinated and unvaccinated fish – in other words how efficiently they shed the virus,” explains Borghild.

Importantly, she stresses, these challenge tests are going to involve two separate year classes of salmon.

“There can be a huge difference in the robustness between year classes, since we are operating with different sub-populations from the base generation” she reflects.