According to Teagasc, Ireland’s first large-scale measurement of methane emissions in beef cattle has yielded “promising” results.
The state agency is undertaking a large-scale characterisation of methane emissions in Irish beef cattle.
It conclusively shows that some beef cattle can produce up to 30% less methane emissions, on average, for the same level of productivity.
The state agency has collaborated with colleagues at UCD and the ICBF for the research.
They are “making strides” towards identifying and ultimately breeding for low methane emitting beef cattle to improve the environmental sustainability of Ireland’s national beef cattle herd.
To date, the relationship between methane output and feed intake has limited the genetic selection of low methane emitting ruminant livestock.
Methane emissions in beef cattle
Teagasc Walsh Scholar PhD student Paul Smith explained:
“In general, on the same plane of nutrition, animals that consume more feed tend to produce more methane on a daily basis.”
“This relationship has so far made it difficult to breed low methane emitting animals without negatively impacting feed intake, which is a key driver of animal productivity, particularly in forage-based production systems.”
However, Teagasc’s Professor Sinéad Waters, Professor David Kenny, Paul Smith, and Stuart Kirwan, along with UCD’s Dr Alan Kelly and ICBF’s Dr Stephen Conroy, working collaboratively through an ERA-GAS funded project ‘RumenPredict’, have recently developed a novel approach to quantifying emissions in beef cattle, capable of disentangling the relationship of feed intake with methane output.
Their study was recently published in the American Journal of Animal Science.
The group showcase the benefits of using a new concept termed residual methane emissions (RME) to select low methane emitting animals without impacting animal productivity.
Residual methane emissions can be defined as the difference between an animal’s actual and expected methane output, based on the quantity of feed consumed daily and its bodyweight.
They calculated RME values for 282 beef cattle undergoing feed efficiency and methane measurements at the ICBF Progeny Test Centre in Tully, County Kildare.
Then, they ranked animals as high, medium, and low on the basis of RME.
“Low RME animals produced 30% less methane, but maintained the same level of feed intake, feed efficiency, growth and carcass output as their high ranking RME contemporaries.”
Breed beef cattle with lower methane emissions
Discussing the significance of the findings, Teagasc researcher Professor Waters said:
“Considering the recent greenhouse gas emissions targets set out in the government’s Climate Action Plan and particularly our requirement to reduce biogenic methane, the ‘RumenPredict’ project demonstrates the future potential to breed beef cattle with lower methane emissions.”
“This project was the first to employ GreenFeed technology to measure methane emissions in Irish cattle.”
Teagasc, UCD and ICBF have deployed this technology across their research facilities. Smith said this “enhances our national capacity to measure methane emissions accurately”.
Head of Animal and Bioscience research at Teagasc, Professor David Kenny, said that it would be “critically” important for the continued economic and environmental sustainability of Ireland’s multi-billon euro beef industry that we continue to apply state-of-the-art science to identify and breed from the most productive, yet low methane emitting cattle.
“This new methane measurement approach, coupled with ongoing work to develop nutrition-based mitigation solutions, will deliver a more resilient Irish beef industry.”
Senior author on the study, UCD’s Dr Alan Kelly added, views the results as “encouraging” findings for Irish beef producers.
He said low RME cattle from the national beef herd produced a third less methane for the same level of performance and feed input.
He added that these emission differences are recorded for all universally accepted metrics of methane expression, be it daily emissions, methane yield or methane intensity.
“Going forward, from a research perspective, we need to understand the biology underlying why these cattle are producing less methane.”
Commenting on the research’s future direction, ICBF’s Dr Andrew Cromie said,
“The work Paul Smith and the team completed has helped us identify the key methane trait (i.e., RME), which we must focus on for methane mitigation in the future.”
“The next step for the ICBF, Teagasc and UCD team will be to broaden the investigation into the relationship between RME and other important traits at a genomic level with a view to harnessing this information within our national beef cattle genetic selection indices.”