Plant & Animal Genomes XVI Conference Plant & Animal Genomes XVI ConferenceJanuary 12-16, 2008
Town & Country Convention Center
San Diego, CA
Jorgen Odegard1 , Anna Sonnesson1 , Hossein Yazdi2 , Theo H. E. Meuwissen2
Disease resistance has received increasing attention in selection programs of farmed fish worldwide. Rapid improvement of resistance to specific diseases may be achieved by crossing domesticated populations with wild populations with high levels of resistance, which may be an option when introducing fish farming into high-risk environments. However, by crossing domesticated and wild populations, considerable losses in productivity should be expected. Backcrossing with the original domesticated population will improve productivity, but usually to the expense of the newly introgressed resistance alleles. To avoid this, selection for both productivity and disease resistance should be applied. However, using classical selection, introgression programs may take long time. This simulation study investigates the potential for improvement of such programs through genomic selection on both traits. Compared with classical selection, genomic selection increased rate of genetic gain, with the largest effect on lowly heritability traits only recorded on sibs of selection candidates (typical for diseases), increasing genetic gain per generation up to 80% compared with classical selection. At the same time, rate of inbreeding was considerably reduced, again with the largest effect in scenarios selecting on disease traits with low heritability. Hence, for a given rate of inbreeding, higher selection intensities can be tolerated for genomic selection. The results indicate that genomic selection can provide a crossbred population with improved disease resistance combined with high productivity substantially faster than traditional selection schemes. However, genomic selection of crossbred populations is rather complicated, as LD between marker and QTL alleles may differ between the founder populations.