18 June 2015
Breeding for Improved Disease Resistance in European Farmed Fish
Improving the genetic resistance of farmed fish to some of the most problematic infectious diseases in European aquaculture is the goal of Work Package 1 (WP1) of the FISHBOOST project. In year 1 of FISHBOOST, a series of disease challenge experiments have been undertaken on populations of juvenile fish with known pedigree. The data collected from these challenges will be used to quantify the genetic variation in disease resistance in these populations, and to develop genetic markers that can be used to find underlying resistance genes and to breed more resistant stocks.
Infectious disease outbreaks present one of the biggest threats to reliable and sustainable production of finfish in Europe. During such outbreaks, typically some fish in a population are much worse affected than others. This variation is due to both genetic and environmental factors. Quantifying and characterising the genetic factors can lead to development of more resistant stock via selective breeding programmes.
In WP1, the following disease challenge experiments have been undertaken during year 1 of FISHBOOST. The experiments incorporate viral, bacterial and parasitic diseases in several finfish species and are typically collaborative projects between industrial and academic partners. - Flavobacterium in rainbow trout (rainbow trout fry syndrome) led by INRA in France - Koi Herpes Virus in common carp led by University of South Bohemia in Czech Republic - Viral Nervous Necrosis in sea bass led by Ferme Marine du Douhet and Ifremer in France - Pasteurellosis in sea bream led by University of Padova in Italty - Sparicotyle chrysophrii in sea bream led by Andromeda and HCMR in Greece - Philasterides dicentrarchi in turbot led by CETGA in Spain |
![]() First turbot trial at CETGA |
The fish samples from these studies will now be genotyped using Restriction site Associated DNA (RAD) sequencing, and (in some cases) microsatellite markers for parentage analysis. The RAD-Seq data will generate new genetic markers dispersed throughout the genomes of each of the fish species, and analyses will be performed to determine which markers are associated with disease resistance.
In several of these studies, siblings from the same set of families will be recorded for various production efficiency traits (WP2). This is possible due to the large family sizes of the species, and this will enable powerful assessment of the genetic correlation between disease resistance trait and production traits which is important for commercial application of the results
The disease resistance challenges have largely been completed in year 1 of FISHBOOST. The sequencing and family assignment will occur in year 2, and the results of the analyses of genetic resistance in year 3.
The results of the experiments will then be applied to breeding programmes through family selection and the development of genetic marker tests for resistance genes. This improvement of genetic resistance of farmed fish stocks in Europe through selective breeding will contribute to the control of infectious disease outbreaks in aquaculture.
In several of these studies, siblings from the same set of families will be recorded for various production efficiency traits (WP2). This is possible due to the large family sizes of the species, and this will enable powerful assessment of the genetic correlation between disease resistance trait and production traits which is important for commercial application of the results
The disease resistance challenges have largely been completed in year 1 of FISHBOOST. The sequencing and family assignment will occur in year 2, and the results of the analyses of genetic resistance in year 3.
The results of the experiments will then be applied to breeding programmes through family selection and the development of genetic marker tests for resistance genes. This improvement of genetic resistance of farmed fish stocks in Europe through selective breeding will contribute to the control of infectious disease outbreaks in aquaculture.