Breeding cattle for lower methane emissions
Take-home Message: Genetic variation in methane yield highlights the possibility of breeding cattle for naturally lower methane emissions. BSAS 011 (2012)
Selective breeding from cattle and sheep that are shown to naturally produce less methane is one promising way to achieve lower herd methane emissions.
Recent research has provided evidence of this natural variation occurring in Australian Angus cattle.
Certain animals were shown to produce significantly less methane than others in the test herds when feed intake was the same.
In order to study natural variation in methane emissions, researchers calculated the methane yield (MY) of individual cattle. MY is the amount of methane produced for a given quantity of feed consumed (l/kg of dry matter intake (DMI)) and comparisons of this value can show whether an animal produces more or less methane than another after equal feeding.
The report puts forward early-stage, but encouraging, evidence that differences in the genetic make-up of individual cattle can result in different methane outputs.
Data was collected from 280 yearling-age Angus cattle in experiments across two years, in which methane production was measured whilst animals were fed a fixed daily quota of roughage diet. Different sires were equally represented so that any effects of relatedness could be noted.
A threefold range in MY values was observed amongst the yearling Angus cattle tested (14.6 – 57.7 l/kg DMI).
While methane production (MP, l/day) was shown to increase as DMI and live-weight (LW) increased, MY was not. It was shown to be mostly unrelated to DMI and LW, therefore implying that it may be possible to select desirable animals that also produce less methane from their feed.
The idea that MY may be a heritable trait was supported by the range of average MY values produced from offspring of different sires.
Sires whose offspring had the lowest average MY values had methane yields that were 19-24% lower than sires whose offspring had the highest average MY values.
Overall, these results show that it is possible to identify cattle that naturally produce less methane from their feed during digestion.
These results suggest that further research into natural variation in methane production and subsequent selective breeding in ruminants may be an effective way to reduce methane emissions whilst rearing animals fit for market.
Full details: Herd R, Bird S, Donoghue K, Hegarty R and Arthur P: “Genetic improvement of Australian Angus cattle for lower methane emissions.”
For further information contact: BSAS on 01314 454508