Frequently asked questions

Below are some common questions ram breeders and buyers often have when starting out with LAMBPLAN or MERINOSELECT.

1.What is an ASBV?

Australian Sheep Breeding Values are an estimate of an animal’s true breeding value based on pedigree and performance recorded information. They are essentially a projection of how that animals progeny will perform for a range of traits.

2.What traits are analysed in LAMBPLAN/MERINOSELECT?

The common traits analysed by LAMBPLAN and/or MERINOSELECT are growth, fat, muscle and reproduction. Optional traits include birth weight, lambing ease, disease resistance, and wool traits.

A description of every individual trait can be found in the accompanying document.

3.What is an Index?

An index combines the values of several ASBVs into one figure.

Which ASBVs are used and their relative weighting depends on the breeding objective that index is looking to highlight. Indexes are a quick way to narrow down which animals to look at however it is very important to look at the individual ASBVs

4.What does the accuracy figure tell me?

The accuracy of an ASBV reflects the amount of information used to estimate the animal’s breeding value, as a percentage of the amount of information needed to calculate its true breeding value with 100% certainty.

An animal with a higher accuracy is more likely to produce progeny as suggested by its ASBVs.

Accuracy increases as more information is gathered on that animal including pedigree information, the animals own performance, performance of half sibs and progeny performance.

5.How does the LAMBPLAN/MERINOSELECT ID system work?

The ID system ensures a unique ID for every animal in any breed of sheep anywhere in the world. 

This system identifies the breed, the flock of birth, the year of birth, and the animals own tag number.

For example, for the animal:


16 0056 2006 060137
Breed code Flock number Year of birth Tag number

6.What is genetic linkage?

Genetic linkage occurs when two or more flocks share common genes. For example when a ram has progeny in multiple flocks there is genetic linkage.

Genetic linkage is what allows animals to be compared across flock and is an essential part of producing ASBVs.

7.What is a management group?

Recording an animal’s performance within a properly assigned management group is what allows for comparison based on genetic merit. Essentially a management group keeps all non-genetic (environmental) influences at a constant amongst the group so that the measured difference in performance is due to genetic influences.

Please refer the Quality Assurance Breeders Manual for guidelines on appropriate management group structuring.

8.How long does it take before my ASBVs are meaningful?

The real benefit from ASBVs comes when you have a complete generation of records, that is, when animals first recorded as lambs become parents themselves. The ASBVs increase in accuracy and predictive power considerably.

It will usually take about 2 to 3 years to build up the useful bank of information however previous years information can be added to speed this up

With LAMBPLAN/MERINOSELECT you can add previous year’s pedigree and performance information at no cost.  This option allows you to build up more data and hence receive more reliable ASBVs within a shorter time period.

9.When I buy an animal with ASBVs, do those ASBVs and its LAMBPLAN/MERINOSELECT ID go with the animal?

Yes the ID and relevant ASBVs do go with the animal. The same ID stays with the animals for life and is used so that the system is able to pick up the pedigree and past information on that animal. On entering a new flock the individual animal will keep its own ID however any subsequent progeny will take on the flock code from the flock in which they are born.