ONE of the most iconic images at any bull sale occurs during the pre-sale inspection. Over the course of a morning, sale bulls will be inspected by producers with hands full of catalogues, supplementary sheets, and loose notes.

While each of these various items contain essential data and information to be factored into the purchase decision, it is important to know what the data means and to know the difference between ‘nice to know’ and ‘need to know.’

The starting point for many producers is to consider the genetic potential of the bulls presented and their suitability in meeting specific breeding objectives.

As the number of genetic traits that have EBVs available increases, the complexity of the data on offer has also increased. For many people, the amount of data on offer can become overwhelming.

The risk of ‘switching off’

Unfortunately, this feeling of data overload can result in a number of reactions that can lead to less desirable outcomes. The first is that producers simply “switch off”. When this happens, they fall back on looking only at a bull’s physical appeal and if anything is considered, it’s the raw data published in the supplementary sheets.

The concern with ‘switch off” is that a bull’s physical appearance does not always reflect his genetic potential or suitability to a particular breeding objective.

Raw data shows how that bull as an individual has grown, and what he weighs to that point in time. It reflects his interaction with that particular environment and nutrition. There really is no way to know if the progeny that will be bred by that bull will reflect that level of growth in a different environment.

Not all producers ‘switch off” and look only at raw data. Many choose two or three EBVs that they consider of importance and rank their bulls using these traits.

However there are a few risks in this approach. Using only one or two traits to make major selection decisions can have longer term implications for a herd. Many traits have correlations that will result in other changes occurring in a herd that may actually take the production of a herd backwards as a result of changes in mature cow size, less fatness or lower growth.

It is easy to appreciate the frustration felt by some producers who look at the information they are offered and then try to determine what to do with it all.

Target markets and selection indices

One of the more effective ways to understand and use the data that is provided is to start with the data that most closely aligns with the program a producer is operating. Producers looking for bulls should be able to describe themselves as being a producer who targets a specific market with their steers and surplus heifers, and either breeds or buys replacements.

Using these broad descriptions, producers should be able to find within their chosen breed a Selection Index that applies to their program. Most catalogues provide the description of the characteristics of the selection indexes, so it’s possible to choose the one closest to the program operated by each individual.

The benefit of the selection index is that it brings the large number of EBVs into a single figure. The selection indexes effectively rank animals considering the relevant growth, carcase & fertility attributes of each animal. The calculation already allows for correlations between traits, which provides a more balanced selection decision on bulls most suitable for use within a particular commercial enterprise.

This process is a more efficient way for producers to work through the data they have been offered on individual bulls. It also means that if there is a need to find a bull that “ticks all the boxes but “also has a bit more of this trait,” a producer could look at bulls that rank well in the chose index, and then from that group choose those which also rank well for their preferred trait.

In approaching their data use this way, their overall selection remains pretty balanced across the traits, with slightly more emphasis on one or two traits that mater in their own herd. This overarching balance should prevent a herd direction changing too much as the result of single trait selections.

A few points to be aware of

While selection indexes work very well as a tool to start the discussion on bulls, it is important to look over the range of reported traits to ensure that the individual bulls being considered do not have any predisposition towards traits that are unfavourable in a particular program.

The nature of selection indexes does mean that some animals may have a high index value – reflecting several traits that have economic importance. However, that same animal may also have individual EBVs that are unfavourable for some producers.

A typical example may be a bull with high 400 and 600-day weights, but very low Calving Ease.  Even with a lower calving ease the bull may still have a high selection Index figure.

This doesn’t mean the selection index is less valuable. Instead, it highlights the need to check the bulls that have been ‘drafted into consideration” to ensure they meet specific requirements of a breeder.

A second consideration is to recognise that the system used to develop selection indexes – BreedObject – allocates a degree of emphasis for each EBV.  The emphasis used by BreedObject does not mean that an individual herd will see changes occur in line with this emphasis. It is better to remember when looking at the index to consider the longer-term change that the genetics will bring, as well as the direction of that change.

For raw data that is often included in supplementary sheets, the information is perhaps best considered in the helpful but not essential category of data.  As previously highlighted, a bull’s average daily gain, current weight and scans are a result of the environment that he has experienced to that point.

While that may be helpful to know, it’s difficult to use that to make predictions on his progeny’s performance or the long-term performance of his daughters that are bred into a herd.

In juggling all that data, it may be handy to remember that starting broadly with an index, working down to check individual traits before looking at individual performance is possibly the easiest way to keep track or and understand the data that’s on offer.

 

Alastair Rayner is the Principal of RaynerAg, an agricultural advisory service based in NSW.  RaynerAg is affiliated with BJA Stock & Station Agents.  He regularly lists and sell cattle for clients as well attending bull sales to support client purchases.  Alastair provides pre-sale selections and classifications for seedstock producers in NSW, Qld, and Victoria.  He can be contacted here or through his website www.raynerag.com.au