
TRIALS assessing live weight gains in weaners grazing the legume fodder crop leucaena across northern Australia are about to kick off.
In an interesting twist, the work will track the weight gains of the Brahman cattle through the supply chain, whether they go to feedlots, live export or direct to slaughter.
The three-year $150,000 project, co-funded by Meat & Livestock Australia and The Leucaena Network, will involve three producer demonstration sites: the Blennerhassett family's Goshen Station at Mt Garnet, Pinnarendi Station at Mount Surprise and the Northern Territory Department of Primary Industries' Douglas Daly Research Farm.
Weaners will go in at six months, grazing several varieties of leucaena until they hit their target weights for the various markets.
Executive officer with The Leucaena Network Bron Christensen said the aim was to determine whether cattle coming off leucaena demonstrated any difference in the ability to gain weight throughout the supply chain to those coming off pasture.
How the difference in wet and dry seasons affects weight gains will also be studied.
Ms Christensen said live weight gain was the focus of the latest leucaena research because its uptake largely comes back to enterprise viability.
Millions has been invested in leucaena research over the years, including the development of a psyllid-resistant variety, and it has been shown to reduce methane emissions intensity by up to 20 per cent.
It is heralded as a way to increase carrying capacity in northern and coastal Queensland, reduce age at turn-off and extend feedbase quality further into the dry season.
Improving marketing windows
In the Northern Territory, live cattle export suppliers are finding leucaena offers the potential for weight gains during the dry season which could see more lucrative marketing windows targeted.

At Blackbull Station, Douglas Daly, Brahman steers gained up to 100 kilograms last dry season in a small trial area where the Cunningham variety was planted in improved jarra grass.
Blackbull is a 15000 hectare freehold cattle and hay operation owned by Peter Maley and Tory Angus which runs 6500 head and typically produces for the live feeder steer trade, turning off two-year-olds at 280 to 380 kilograms.
Most of the property is improved to a mixture of jarrah, buffell and strickland and 60ha of leucaena was trialled last year.
Weed competition meant the majority of that had to be replanted this year but manager Logan Reid said the 30 steers that did manage to graze one 20ha paddock, spending 70pc of their time between the end of May and October in the leucaena, put on an average of 100kg where they would normally only maintain their weight in that period.
If that could be replicated on a larger scale, it would make a massive difference to what could be achieved at Blackbull, he said.
"We could aim to market steers in that December to January bracket when the live export trade struggles for supply and prices go up.
"It could also mean a larger carrying capacity during the dry season."
Mr Reid said the initial trial went into recently-established jarra so this year they have planted another 47ha into more established pasture in the hope of reducing weed competition.
They have also tried other varieties, including Wondergraze and Redlands, and planted in three different row spacings to attempt to determine the right balance of leucaena-to-pasture for their region.
The trials are being run in conjunction with Meat & Livestock Australia.
"Our hope is to eventually get 1000ha of leucaena in. It's a supplement to the other improved pasture, when it backs off over the dry season," Mr Reid said.
"It's challenging to work out where and how to plant and it also needs to be managed - if it is let go to seed it will spread where you don't want it and it has to be kept at a grazable height.
"In the east, they are cultivating prior to planting but our high rainfall (1100mm) means erosion could be an issue."