Breeding ruminant livestock that produce less methane while, at the same time, achieving higher levels of performance, is feasible.
It has already been confirmed that, under the same farm conditions, there will be variations in relation to the amount of methane produced by animals within the same group.
However, under the same farm conditions, there will be variations in relation to the amount of methane produced by animals within the same group.
These were the key messages delivered by Sam Boon, who heads up the Signet sheep breeding programme at AHDB, courtesy of his presentation to the recent beef and lamb open day – hosted by the Agri-Food and Biosciences Institute (AFBI).
The event was held at the institute’s experimental farm close to Hillsborough in Co. Down.
“Some of the differences in methane production levels achieved by ruminant livestock can be attributed to genetic factors.
“The beauty of genetics is that, unlike health and nutrition, it delivers a cumulative benefit across the generations,” Boon said.
“It’s locked in. So, where health is concerned, we do a treatment this year and it impacts on the animals. But we have to do the same thing again next year in order to keep this going.
“But with genetics we can build on the process: it delivers a cumulative impact which is sustainable into the future within a population,” he added.
Breeding ruminant livestock
According to Boon, the benefit of genetic improvement, secured in the UK over the past 40 years across all livestock sectors, is now worth about £14 million on an annual basis.
“The specific figure for the beef sector works out at £7 million,” he said.
There are two ways of reducing methane output within the ruminant livestock sectors – one is through direct selection.
“The other is through a process of indirect selection,” Boon commented.
Direct selection involves the actual measurement of the methane emissions produced by livestock.
Where sheep are concerned, this work is carried out under the auspices of the ‘Breed for Change’ programme.
“We are measuring methane production levels under commercial production environments, courtesy of sheep within an actual grazing environment.
“This is the gold standard approach. The approach is also allowing us to CT scan the sheep involved in the trial.
“This allows us to measure rumen volumes. It should be possible to gauge how this relates to actual methane production levels. Cattle are that much bigger,” Boon outlined.
The AHDB representative admitted that it is harder to measure methane emission levels with cattle:
“The way around this challenge, is to measure the feed efficiency of the animals.
“We know there is a high degree of correlation between the efficiency with which animals convert feed intake into meat or milk and the associated levels of methane that are produced.”
Indirect selection involves the assessment of efficiency-related indices.
“Where dairy sires are concerned, the availability of an enviro index is now available,” Boon commented.
“So we also know that there is a more general association between growth rates, feed conversion and maternal traits, linked to the overall efficiency secured within a beef and sheep enterprise.
“The higher the levels of efficiency secured then the lower will be the levels of associated methane that are produced,” he explained.
