Genetics is the knowledge of how genes affect the way an animal looks or performs. It includes ‘heritability’, which describes how much of a trait is passed on from the parent to the offspring and ‘correlation’, which explains how one trait is related to another.
A wealth of genetics knowledge already exists and allows us to predict the performance of progeny, based on the performance of their sire or dam and other relatives.
The genetic merit of sheep and their estimated breeding values are predicted by directly measuring the performance of traits at particular times or by using indirect measures of a trait, that is, information about other traits that are related to the trait in which we are interested.
However, a sheep’s own performance is the result of both its genetics and the ‘environment’. The important environmental influences include nutrition, climate, diseases and parasites, whether the animal was a single or twin, whether its dam was a mature ewe or a maiden, its sex, its age relative to its flock mates and other factors about how the animal was managed.
To predict the performance of a sheep’s progeny based on its genetics, we need to exclude the environmental factors. Also, to increase the accuracy of this information we include performance data from its relatives: its sire and dam, siblings and half-sibs (i.e. brothers and sisters and half-brothers and half-sisters) as well as other relatives, especially the individual’s own progeny.
The result calculated is the ‘estimated breeding value’. For sheep in Australia, this is calculated and published as an Australian Sheep Breeding Value (ASBV) in LAMBPLAN (for meat sheep breeds) or MERINOSELECT (for Merinos). When ASBVs are calculated they also incorporate all that is known about the heritability of a trait and the correlations it has with other traits.
ASBVs are more accurate than using the raw measurement from a trait, especially for traits that have lower heritabilities, a smaller range of expression or lower accuracy of measurement. ASBVs also allow unrelated animals from different studs under different management conditions to be compared objectively.
ASBVs are only available for sheep when performance data has been collected using procedures outlined in the Sheep Genetics’ Quality Assurance Manual. Many sheep studs provide ASBVs for a range of traits on each of their sheep.
The Sheep CRC conducts genetic research through its Information Nucleus. This is a group of 8 flocks located across Australia, using many breeds and diverse industry sires to:
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ASBVs stand for Australian Sheep Breeding Values. They are the national language for benchmarking sheep based on their genetic merit and are produced by Sheep Genetics. ASBVs describe a sheep’s breeding value for a trait, e.g. fleece weight or body weight, and express the relative breeding value of sheep across different breeding flocks of that breed (or across breeds in the case of Terminal breeds). They are equivalent to estimated breeding values (EBVs) used in other livestock industries e.g. BREEDPLAN in the beef cattle industry.
The Merino Sheep Breeding Trainer Guide has been developed by Sheep CRC and Meat & Livestock Australia to allow vocational and education trainers (primarily in the TAFE, Agricultural College and School systems) to deliver up to date knowledge and skills in the area of Merino breeding to their students. It is designed to be used in conjunction with three Power Point presentations, produced by the Sheep CRC on developing a breeding objective, selecting a stud and rams and selecting ewes.
Selection Assist enables producers or their advisors or classers to compare results from different breeding directions, so as to choose which is most applicable to their flock. The program predicts the likely outcome of selected breeding objectives. It also shows the impact of reproductive rates and where the progress can come from within a flock.
Visually assessed traits are included in the breeding objective of all stud and commercial sheep breeders, regardless of their target market or environment.
Sheep Genetics provides you with practical information on the genetic potential of your sheep. Sheep are ranked according to various production characteristics using Australian Sheep Breeding Values (ASBVs) across flock or Flock Breeding Values (FBVs) within flock. See Sheep Genetics brochures available for download below. To download other publications click here.
Download the genetics publications below.
This Conference combined world class science with its practical application.
This Conference combined world class science with its practical application.
These proceedings are from the showcase conference of the Australian Sheep Industry CRC 'Wool meets Meat - tools for a modern sheep enterprise' conference held in Orange (NSW) during 2006.
A new training initiative is being rolled out nationally to help sheep producers combine top genetics with superior ewe feed management to boost reproduction rates and productivity. West Australian producers have an opportunity to attend a Bred Well Fed Well workshop, funded by Meat & Livestock Australia (MLA) and Australian Wool Innovation (AWI) through their Making More from Sheep initiative. The workshop was developed by...
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http://www.sheepcrc.org.au/information/news/bred-well-fed-well-is-coming-to-western-australia-08-02-2012.php
While a wetter than average summer in South Australia has raised the prospects of flystrike problems for many graziers, Phil and Ann Hammat are confident their flock will come through unscathed. The Hammats, of Baderloo Poll Merinos, Spalding, have been selecting for a plain body type and proactively applying preventative chemical treatments since they ceased mulesing in 2004. Their flock of 900 stud Poll Merino ewes and 350...
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http://www.sheepcrc.org.au/information/news/better-breeding-delivers-against-flystrike-sa-case-study-24-01-2012.php
In the midst of Western Australia’s tough fly season, Dandaragan sheep producer Peter Wilkinson is confident his sheep will stand up to the test thanks to a long-term investment in genetics. Together with parents Ron and Deanna, Mr Wilkinson operates the Challara Merino Stud, which first embraced breeding for body and wool types that were less susceptible to flies almost 20 years ago. “We were seeing a lot of fleece rot...
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http://www.sheepcrc.org.au/information/news/better-breeding-delivers-against-flystrike--wa-case-study-19-12-2011.php
A new wave of young researchers from the Sheep CRC is building future R&D capacity for the thriving Australian sheep industry. Postgraduate researcher Sam Clark is one of 31 doctorate and masters students undertaking the Sheep CRC postgraduate education program.
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http://www.sheepcrc.org.au/information/news/new-wave-of-sheep-genetic-researchers-deliver-for-the-future-06-07-2011.php
