WORK under way on Dorpers in a satellite flock in Western Australia will help create better eating quality lambs, without compromising yield or growth.
The Resource Flock began life in 2007 as the Information Nucleus Flock under the Sheep Co-operative Research Centre (CRC), but is now run by Meat and Livestock Australia.
Professor of animal genetics Julius van der Werf, University of New England, Armidale, said the project would determine where Dorpers were situated in terms ofmeat yield and quality.
The focus then shifts to the development of genotyping tools, adding to traditional methods such as pedigree and performance recording.
Prof van der Werf, also the program leader for the genomics program in Sheep CRC, said this was a long-term project to ensure breeds such as Dorpers had the tools to produce high yielding carcases while maintaining eating quality.
The project involves the slaughter of the lambs, all of which are DNA tested, to collate data on traits such as intramuscular fat (IMF) and tenderness.This information is used to develop a genomics test, which in turn will then be used to calculate a breeding value, giving producers an estimation of the breeding value of that animal from an early age.
“The idea is to create an index which can balance these otherwise antagonistic traits, so producers will be able to select for high meat yield without reducing eating quality”, Prof van der Werf said.
“Those eating quality traits are important because if you keep just selecting for meat yield and growth, then the intramuscular fat level goes down.
“It’s quite likely we can measure lean meat yield in abattoirs very soon and we’re also working with MLA and the CRC on measuring intramuscular fat at chain speed in abattoirs.”
He said this meant processors would eventually be able to develop a price signal for these traits, however, this may take several years.
“If you pay for the trait, it’s an incentive to breed for the trait,” he said.
Prof van der Werf said the genomic test was still about two to three years off commercial release for Dorper producers.
His suggestion at this stage for the best way breeders could use this technology was to select the best ram lambs to test, and, using genomic testing, narrow them down to the best of the group to use for breeding.
A trial being conducted in Western Australia is helping to develop genomic tests for Dorper and White Dorper sheep for hard-to-measure eating quality traits.
Therefore, a producer might genotype 20 young rams, but use the best five for breeding to make better selections,reduce generation intervals and increase genetic progress.