The 2013 dry season is proving a challenging one on many fronts for the majority of beef producers in northern Australia.

Consecutively higher than average wet seasons of 2011 and 2012 were followed by a prolonged 2012 dry season, which, for many producers, failed to eventuate into a 2013 wet season.

As a consequence pasture volumes and surface water availability in many areas are low, and many parts of northern Australia are in the grip of a severe drought.

Combined with broader industry issues including high levels of debt, reduced market access due to the import restrictions on live export cattle and lower cattle prices, the operating budgets of cattle producers are being squeezed.

Despite these factors, it remains imperative to keep in mind that one of the largest constraints limiting profitability of northern beef cattle businesses is the poor performance of extensively managed breeding herds, Ridley AgriProducts technical manager Matt Callaghan said.

“Supplements are one part of the solution to this problem and given the current situation, it is worth reviewing where and how the limited dollars available for supplementary feeding this dry season should be directed,” he said.

In a typical dry season, some producers opt to direct those scarce supplementation funds towards low input blocks or loose licks based on urea and other non-protein nitrogen (NPN) sources. Others opt for suspension-based liquid supplements.

Such supplements promote the consumption of low- protein, high-fibre pastures leading to a liveweight response off blocks or loose licks of roughly 0.1 – 0.3 kg/day above pasture alone.

In many regions, it was important to consider that between July and November this may represent a reduction in liveweight loss rather than liveweight gain, Mr Callaghan said.

These effects were recently demonstrated in a late dry season supplementation trial at Fletcher View, Charters Towers, by James Cook University. Mixed age, heavily pregnant Bos indicus breeders grazing buffel grass dominant pastures were supplemented with Rumevite 30pc Urea + Phosphorus blocks between October and December last year.

Diet quality (as measured by faecal Near Infra-Red Spectroscopy), was at maintenance requirements (6pc dietary crude protein; CP) at commencement of the trial, but had reduced to 4pc CP (below maintenance) by December.

Similarly, digestibility estimates (48-50pc) and dietary non-grass values (≤10pc) suggested that weight loss would be expected in unsupplemented, heavily pregnant breeders.

In this trial however, breeders on average consumed blocks at 109g/head/day and consequently maintained liveweight and body condition score over the late dry season.

The benefits accruing from dry season urea feeding are attributed to reducing breeder mortality and retaining body condition score (BCS), which in turn improves reproductive performance.

“The primary assumption when feeding NPN supplements is that you must a large body of feed at your disposal. If you don’t have pasture to work with, then urea supplements are not an appropriate choice,” Mr Callaghan said.

Other management decisions can have an even greater impact than urea supplements in terms of retaining body condition score on breeders, he said.

While NPN supplements can save the equivalent of 5-10 kg of liveweight/month in many northern conditions, implementation of a strategic early weaning program had an even greater impact, saving 10–15 kg liveweight/month during the dry season.

“There is however an associated cost because the early weaned calves need appropriate supplementation. These would generally be supplements containing both protein and energy,” Mr Callaghan said.

Examples include weaner pellets or vegetable protein meals fed at high rates. A decision to avoid supplementation of early-weaned calves in the dry season was likely to lead to increases in mortality, a reduction in compensatory gain ability, and later age at turn off to meet market specifications. 

The choice of supplement for early weaned calves in the northern beef industry is often driven by constraints around labour, infrastructure and management as well as nutritional considerations.

Radical weaning (< 100 kg liveweight) takes even greater management and more specific supplementation regimes. Regardless of the supplement, the addition of a coccidiostat (monensin-based rumen modifier), plenty of trough space and clean water were all key ingredients when intensively feeding weaners.

The final point of discussion, particularly applicable in dry years like this, revolved around the feeding of energy sources, Mr Callaghan said.

“This is essentially crisis feeding and becomes very expensive because these feeds are consumed at high rates (kilograms/day). Using energy-dense feeds generally leads to substitution of pasture, which does makes it an appropriate choice when pasture volumes are highly limiting,” he said.

Examples include whole cottonseed, molasses and meals or pellets high in vegetable protein meals. Grains were probably best avoided because the reality is that most northern beef properties do not have the infrastructure and time to manage large scale grain feeding programs without a high risk of digestive disorders.

Target stocks for these programs are generally cows or first/second-calf heifers in very poor body condition. Given the prolonged 2012 dry season, continuing well into 2013, there may also be an argument to supplement growing heifers to reach target joining weights later this year.

Similar to weaner feeding programs, careful consideration should be made around the ability to manage the feeding program given operational constraints. The choice of ‘which supplement is best’ should therefore be made at an individual property level.