Environmental influences place the greatest limitations on beef production. While genetic potential may offer tangible improvements for traits that impact levels of production, if the environment is too restrictive, those improvements may never be fully realised.

Environmental limitations include the feedbase underpinning the production system through to temperature extremes. Within these two areas, it is possible to broaden the limitations to include parasites and diseases that are more common in particular locations or within temperature ranges; and plant type and availability of macro & micro elements essential for efficient livestock metabolism.

Perhaps subconsciously, producers do include these factors in their selection process. However, there does seem to be a move by many producers to focus largely on genetic selection as the basis for improvements or increases in production.

There is perhaps a paradox emerging where selection of better genetics has resulted in no improvement in herd production or in some cases a drop in production levels.  This can be attributed to the impact of the production environment.

Reproduction, body condition

The traits that decline more quickly or are more susceptible to the influence of the environment are those associated with reproduction and with body condition. In terms of production and overall enterprise profitability, reproduction is a critical performance trait. There have been many analyses conducted on enterprise profitability.

Consistently these studies show the impact on a business’s profitability from modest increases in reproduction can be significant. The “Proof of Profit from EBV based selection” published by MLA, suggests that for a northern beef enterprise, a modest lift (3pc) in reproduction rates can result in an income increase of 11pc.

Achieving these improvements with genetic selection is certainly possible. The evidence presented in reports such as the “Proof of Profit from EBV based selection” demonstrate the gains that can occur when bulls are selected and used, based on well described and accurate EBVs.

However these gains are often a long-term process and require producers to remain focussed on clear objectives.

Not all producers have time on their side, particularly if their production levels are average of falling below average. While short-term adjustments may be made to mitigate the impact of environmental limitations can be made, such as reducing stocking numbers or using strategic supplementary feeding programs, these are generally stop gap measures.

Longer-term strategies to increase production will often require making changes to a breeding herd.

Crossbreeding

The most effective and positive change that can be made is to adopt a well-designed crossbreeding program. The value of crossbreeding is often greatest in the expression of the lowlier heritable traits – that is, those traits which are most impacted by the environment.

In breeding herds, crossbreeding programs therefore offer the most positive improvement in the factors that have a direct impact on a herd’s productivity and therefore its overall profitability.

The opportunity to utilise breeds that have the greatest ability to adapt to local environmental challenges is one that shouldn’t be overlooked. The Southern Multibreed project, which is funded by the MLA Donor Company and is being conducted by NSW DPI and UNE, has continued to demonstrate the potential of crossbreeding to increase producers’ overall profitability.

The project has shown that Brahman genetics over Hereford or Angus genetics can result in a 14pc advantage from hybrid vigour.

From a production level this advantage would generally mean faster growth, resulting in replacement females reaching puberty at a younger age than purebred females.  This advantage allows producers greater opportunity to select their replacement females to join at an earlier age and potentially set those females up earlier for lifetime production.

Considering the limitations of environmental conditions, this improvement in growth as well as earlier puberty may start to offset some of the restrictions that cause lower production levels in herds – particularly when the environment results in slower growth, later joining and larger cows which may take longer to recover from calving and returning to oestrus.

With the release of Genomic Breeding values, particularly for hard-to-measure traits such as Pregnant in four months, producers with crossbred herds have the increased ability to select genetically within their herds. As well as selecting for those animals that are physically better adapted to the environment, selection for genetic traits can also be done with confidence.

Ultimately achieving increased production requires producers to consider how to operate within the restrictions of their environment.

Taking advantage of well proven opportunities such as crossbreeding, combined with new genomic selection tools may go a long way in ensuring the ‘E’ in ‘G x E’ is not overlooked in the next round of selection.

Alastair Rayner is the General Manager of Extension & Operations with Cibo Labs and Principal of RaynerAg.  Alastair has over 28 years’ experience advising beef producers & graziers across Australia.   He can be contacted here or through his website www.raynerag.com.au