Recent discoveries in molecular genetics have provided the tools for more accurate selection of sheep with high merit for production or disease resistance traits. Genetic markers enable selection within breeds where a desired gene is present, introgression of a gene into other breeds and the establishment of mixed breeds carrying the gene. The DNA tests available to identify an increasing number of useful genetic mutations in sheep are the key to the efficient introduction and maintenance of these mutations in sheep flocks and the test results should be combined with breeding values for other traits controlled by additive genes to optimise genetic gain across all traits. This approach to flock improvement is particularly useful where traits have low heritability, are expensive or difficult to measure, or where the expression is sex-limited. Strategies based on either direct markers or haplotype tests continue to develop as the list of genes known to affect sheep production grows. Because of the ability of some of these mutations to quickly change production levels in flocks it is important that their introduction is matched by the higher management skills required to profitably run high performance flocks.

G. H Davis, John C McEwan, K. G Dodds

Proceedings of the World Congress on Genetics Applied to Livestock Production, Volume , , 04.01, 2006
Download Full PDF BibTEX Citation Endnote Citation Search the Proceedings

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.