There can be significant "variation" in the emissions intensity of phenotypically identical Angus cattle, according to Angus Australia extension manager Jake Phillips.
Subscribe now for unlimited access to all our agricultural news
across the nation
or signup to continue reading
Mr Phillips, Naracoorte, New South Wales, said initial findings from the organisation's low methane beef research project in collaboration with the University of New England found that different Angus cattle can have different emission levels.
He was speaking to Stock & Land at the recent Agriculture Victoria Better Beef conference in Ballarat.
Essentially, two identical black cattle, eating the same amount of feed and gaining the same amount of weight in the same environment can have a different carbon footprint.
"Angus Australia are probably leading all of the breed societies in Australia on this," Mr Phillips said.
"We hope to have a research breeding value out in the next couple of years which would then identify which sires would have a lower methane emission compared to others."
The trials were on their third year of animals going through methane emissions testing and data was now available on the first two years of research.
The cattle were also having other phenotypes, such as weight gain, and their DNA recorded.
The breed society research was aimed at estimating the heritability of low-methane traits in the cattle and determining the correlation between these traits and others, such as weight gain.
"The science tells us that heritability is going to be useful," Mr Phillips said.
"We're also seeing plenty of variation in the emissions phenotypes coming in.
"What we know is that within a population of cattle when there's variation and there's heritability, you can select on it and make change."
Angus Australia's findings stack up with those published internationally.
Ireland
Research supported by the Irish Department of Agriculture found that there was major variation in methane emissions between cattle breeds and importantly, within breeds.
A total of 1500 cattle from 320 AI sires across several breeds, proportionate to the Irish cattle population demographic, were studied over the 70 days prior to slaughter, in a finishing system.
The cattle's individual emissions were measured each day.
The researchers, led by Professor Donagh Berry, found that Limousin cattle came out on top with a lower emission levels, compared to other breeds.
Notably, the average animal across all breeds was found to have methane emissions of 250g a day, according to Prof Berry.
However, there was huge variation where the animal with the lowest emissions emitted 180g of methane/day while the animal with the highest emissions emitted 320g.
The 20 per cent of cattle with the lowest methane emissions emitted an average of 220g/day while 20pc of cattle with the highest emissions emitted an average of 280g/day.
The verified research found that there were more Limousin-sired cattle in the first cohort, with the lower average emissions, and more Hereford and Simmental cattle, in the second cohort, with the higher average emissions.
Holstein-sired cattle were bang in the middle of the two groups and Angus and Charolais cattle were above average, with more emissions than the Holsteins but lower than the red and white breeds.
Prof Berry noted that the findings did not take into account the lifetime emissions of each animal and that there was also huge "variation" within breed.
However, he suggested that even if an animal, such as an early maturing breed like Angus was slaughtered earlier, that may not be enough to gain ground on the lower-emitting, albeit slower-maturing, breeds such as the Limousin.
Last year, Irish Minister for Agriculture Charlie McConalogue described the findings as a "game changer" for Irish cattle farming, as the country's agriculture industry moves to meet its emissions reduction targets.
Prof Berry said breeding for lower-emission emitting cattle resulted in genetic gain of about 1pc a year, not to be shirked at.
That is that if the trait was selected for in farmers' breeding programs, the cattle would have 1pc less emissions each year.
If bulls were selected for lower emissions, while not compromising on performance, a reduction of at least 20pc in beef emissions could be achieved by 2020.
Mr Phillips hoped Angus Australia would have similarly strong results from their own research over the next couple of years.
