Steer trial puts grazing theory to the test

The demonstration was set up to compare the performance of steers from ten different breeds and crossbreeds under the latest grazing land management recommendations.

It was also about answering how much Brahman content a steer being produced in Central Australia can have in order to gain production benefits before meat eating quality is affected.

Pastoral production officer with the NT Department of Primary Industry and Fisheries, Chris Materne said a good deal of grass modelling on different ways to graze cattle in the north, such as stocking numbers, rotation and spelling, had been done ‘on the desktop’.

That had come up with the best strategies for improved land condition and optimum business outcomes and the producer demonstration was about putting those strategies into practice.

Seven properties from the South Australian border to Tennant Creek each provided up to eight 200 kilogram weaner steers for the research.

The cattle were grown out to 2.5 years on the Northern Territory Government’s Old Man Plains Research Station near Alice Springs under the primary management practice of matching stocking rate to carrying capacity.

A forage budget, used to determine stocking rate for seasonal conditions, was undertaken before they entered the trial.

The steers were put in a two paddock rotation to incorporate pasture spelling, which is another key grazing land management strategy.

Steers were mustered quarterly to collect performance data and were also monitored remotely.

While the full carcase feedback details are still to come, with the steers being processed in South Australia this week, preliminary findings indicate that pasture quantity and quality played the key role in weight gain.

Mr Materne said the majority of steers surpassed their target weights of 575kg at 30 months, averaging weight gain greater than .5kg per day with a p8 fat depth greater than 6mm.

Genetics came into play towards the end of the trial when the steers began to separate in terms of fat coverage, he said.

The range of the last p8 fat depth measurements was 5 to 14mm.

Mr Materne said producers in central Australia were exploring quality beef markets for premium prices but the perception was Meat Standards Australia graded beef could only be produced during exceptional seasons.

“We now know we can consistently supply cattle for top-end markets under variable and unpredictable climates, by using certain grazing strategies,” Mr Materne said.

“We want to hit the premium markets so if breed does influence that, producers may need to look at limiting certain breed content - we expect the carcase feedback to provide much more data on that.”

Mr Materne said to change the breeding of a herd in Central Australia, it was at least a ten-year process.

“So we want to know exactly what the benefits of that are before making that decision,” he said.

The steer challenge was an extension of long-term quality grazing trials set up on the research station to investigate the effect of different strategies on land condition, quality beef productivity and business profitability.

The production aim of the work, involving 450 Droughtmaster breeders, is to consistently produce two-and-a-half year old grass fed steers direct to slaughter and MSA grading, regardless of season.

By implementing permutations of three key grazing strategies - spelling, long-term carrying capacity and stocking rate adjustment for season variability - researchers and cattle managers have been able to lift stocking rates at OMP from .5 to 2.2 head per square kilometre under extremely variable and unpredictable conditions.