Location: Cool and Cold Water Aquaculture ResearchTitle: Genomic Selection For Bacterial Cold Water Disease Resistance In Rainbow Trout Reveals Large Within-Family Variation That Cannot Be Exploited In Traditional Family-based Selective Breeding
|Leeds, Timothy - Tim|
|MARTIN, KYLE - Troutlodge, Inc|
|Wiens, Gregory - Greg|
|PARSONS, JAMES - Troutlodge, Inc|
Submitted to: Plant and Animal Genome
Publication Type: Abstract Only
Publication Acceptance Date: 12/1/2015
Publication Date: 1/10/2016
Citation: Vallejo, R.L., Leeds, T.D., Martin, K., Evenhuis, J., Gao, G., Wiens, G.D., Parsons, J., Palti, Y. 2016. Genomic Selection For Bacterial Cold Water Disease Resistance In Rainbow Trout Reveals Large Within-Family Variation That Cannot Be Exploited In Traditional Family-based Selective Breeding [abstract]. Plant and Animal Genome. P0470.
Technical Abstract: Selective breeding is an effective strategy to improve resistance to specific pathogens, and thus has the potential to mitigate antibiotic use in aquaculture. Large family sizes of aquaculture species permits family-based selective breeding programs, but the need for specific-pathogen-free nucleus populations precludes the ability to exploit within-family genetic variation. Genomic selection (GS) simultaneously incorporates dense SNP marker genotypes with phenotypic data from related animals to predict animal-specific genomic breeding value (GEBV), which circumvents the need to measure the disease phenotype in potential breeders. Here, using a commercial rainbow trout (Oncorhynchus mykiss) population, we provide empirical data demonstrating the power of GS to exploit within-family genetic variation for bacterial cold water disease (BCWD) resistance. Animal-specific GEBV was derived for pathogen-naïve breeding candidates based solely on genotypic data after estimating SNP effects in a related training population. Pairs of full-sib sisters with divergent GEBVs for BCWD resistance were mated to a common “random” sire to test the hypothesis that progeny from high-GEBV dams exhibit greater BCWD resistance than progeny from low-GEBV dams. Across 46 paternal half-sib families, the average survival following experimental BCWD challenge in progeny from the high-GEBV dams (44.5%) was 79% greater than in progeny from the low-GEBV dams (24.9%). This response to one generation of GS is attributable solely to within-family variation that cannot be exploited in traditional family-based breeding programs. Furthermore, genome-wide association analysis in this population identified moderate- to large-effect QTL distributed among 17 chromosomes explaining up to 53% of BCWD variance. Similar genetic architecture for BCWD was observed in other unrelated rainbow trout populations.