DNA test offers gains

Dr Lee has been working with some of the studs using DNA testing developed by the Sheep CRC which can predict many economically important traits.

Tests are also available for Poll status to identify any Poll animals which are carriers of the horn gene, and parentage verification.

He said the technology had substantial benefits to studs and the industry as a whole by improving meat and wool quality and reproduction.

For example, a blood sample from an animal was collected on a specific bar-coded card by making a small cut on the ear, and sent to Sheep Genetics or the Sheep CRC for DNA testing.

The 12k Low Density Single Nucleotide Polymorphism test provides information on 12,000 genetic markers measuring a large number of traits including those not normally available until later in life, such as adult wool weight or mature weight, or reproduction, and for traits that are difficult to measure on breeding animals, such as lean meat yield and intramuscular fat.

The test is available for four breeds - Merino, White Suffolk, Poll Dorset and Border Leicester, where enough animals and traits have been measured in the Sheep CRC Information Nucleus Flock and the Sheep Genomics flock as a reference population.

The early adopters of LD SNP tests have typically been studs that are already doing significant measurements and performance recording and looking for a further ways to increase genetic gain.

Some 20,000 parentage verification and 4000 LD SNP tests have been conducted since the tests became available, but in the next 12 months it is expected that use of the test will increase among Merino, maternal and terminal sire breeders.

"We are seeing many breeders and consultants looking at the technology and learning about it so we are expecting increased testing in the next 12 months," Dr Lee said.

At next month's Sheep CRC conference Concept to Impact in Adelaide on July 9, Dr Lee will outline how genomics is being used in stud breeding programs to increase genetic gain.

He said testing was most common in Merinos after breeders had an opportunity to evaluate rams based on growth and wool.

This reduced the need to test all animals and instead breeders could focus on the individuals with the highest ranking ASBVs.

"Modelling indicates that genomic testing around 20 per cent of the ram drop is expected to give over 80 per cent of the potential gain if all rams are tested," he said.

"If you are needing five new rams for next year's ram team they will likely come out of the top animals based on ASBVs as yearlings. It is a bit like football - if you are low on the ladder there isn't much chance of making the finals, or in this case making the ram team."

* Full report in Stock Journal, June 19, 2014 issue.