The Value of ASBVs for the Commercial Producer

BRETT WILSON
DOHNE DATA MANAGER
LEURA, NEW SOUTH WALES

“Dohne breeding value, combined with a Classer’s Grading system means Dohnes have the most advanced across-flock evaluation system for sheep in Australia.”

IMAGINE you are a commercial Dohne breeder at a multivendor Dohne sale to purchase some rams for your flock, but the rams are hard to compare.
The rams are from different areas within the state (or country), have had different levels of nutrition, vary widely in age, some are twins, others are from a maiden ewe, etc.
How do you even the playing field to compare these rams as best as possible?
It is important that breeders focus on the individual ASBVs that will enhance their flock, based on their breeding objectives.

Breeding Values
Genetic improvement is one of the fundamental tools available to sheep producers to increase the productivity of their flock.
The Australian Dohne Breeders Association (ADBA) has teamed up with Sheep Genetics (SG) who provides a world’s best practice genetic evaluation service, to deliver credible and accurate breeding values.
SG provides information to help sheep producers more effectively select sheep using Australian Sheep Breeding Values (ASBVs) and Indexes.
The system is focused on maximising dollar returns for commercial sheep producers while ensuring conformation, quality and type standards are improved.

What are ASBVs?
ASBVs describe the expected performance of a sheep’s progeny, not just the performance of the sheep itself. An ASBV therefore describes the breeding value of a sheep – and as a breeder; that is what you need to know.
ASBVs are generated by Sheep Genetics and are designed to be used by ram breeders and commercial producers to compare the genetic potential of rams (and ewes), for a range of production traits; across flocks, independent of environment and management.
Pedigree performance records allow all Dohne ASBVs and Indexes to be reported across-years and across- flocks.
The result is that the predicted performance of all Dohnes from Registered Dohne ram breeding flocks can be directly compared, regardless of whether the stud is large or small, old or new, in a dry or wet area, north or south.
Dohne ram breeders produce ASBVs for major measured performance traits including; weaning and post weaning weight, fleece weight, fibre diameter and CV of fibre diameter. Many breeders
also record eye muscle, fat depth and reproduction.
Dohne ASBVs have increased accuracy by accounting for factors that can improve the ability of measured information to describe a sheep’s breeding value.
Factors accounted for include the trait heritability, if the sheep was a twin or single, date of birth of the lamb, the sheep’s pedigree performance and difference in environment between groups.

ASBV trait name, abbreviation and description
Most trait name abbreviations will have an extra letter that describes the age the trait is being reported for. W before the trait abbreviation indicates the Weaning age (6 up to 16 weeks
of age); P is Post-weaning age (7 up to 10 months of age); Y is Yearling age (10 up to 13 months of age).

Percentile Band Report

PERCENTILE BAND reports are critical because they allow breeders to compare the standard and scale for a trait. A report like table 1, shows the range of ASBVs across all Dohne sheep in the current year of drop.
This allows comparisons between individual rams and the entire Dohne drop for each trait and index. For example; a ram that is above the 5% band value will be one of the highest performing sheep for that trait. Close to the 50% band will be around average.
Lower than the 90% band will be one of the lowest performing sheep for that trait. It is important to realise that breeders don’t always want to be at the high end of the bands. Where a breeder wants to be positioned along the scale depends on the breeding objective of the flock.

Table 1 Dohne Percentile Band Report from 7th February 2019.

A balanced objective
ASBVs can play an integral role in the selection of rams and ewes for specific breeding objectives, assisting breeders, both stud and commercial, to make faster genetic gains in the areas of those selected traits. It is very important however, to visually (subjectively) choose sheep based on your environment, management and personal choices.

Additional Information can be found at:
• dohne.com.au
• sheepgenetics.org.au/home
• ramselect.com.au/#/home