reducing emissions from livestock fact sheet

The Reducing Emissions from Livestock Research Program (RELRP) is funded by the Australian Government to develop practical on-farm options to reduce emissions from livestock while maintaining, and even increasing productivity. The RELRP will deliver information and technologies to help producers reduce methane and nitrous oxide emissions on-farm. The economic and environmental benefits of adopting farming practices that lower livestock emissions may include:

• improving the conversion of feed to energy
• reducing nitrogen losses from intensive production systems and
• the potential to create offsets under the Carbon Farming Initiative¹.

Direct livestock emissions account for around 11 per cent of Australia’s greenhouse gas emissions. This includes:

• methane emitted directly from livestock and
• methane and nitrous oxide resulting from livestock manure and urine.

Methane and nitrous oxide are significant greenhouse gases as they are 21 and 310 times more potent than carbon dioxide over a 100 year period². Therefore, any reduction in these emissions from the livestock sector will play an important role in  Australia’s efforts to reduce greenhouse gas emissions and mitigate future climate change. The key areas of focus for the RELRP include measuring methane emissions from livestock, adapting rumen function and managing and measuring emissions from manure.

Measuring methane emissions from livestock

Accurate measurement of methane emissions from livestock is required to assess the effectiveness of methane reduction methods. These techniques may be used to measure on-farm reductions in methane emissions under future offset markets. The RELRP is assessing innovative methane measurement techniques for their accuracy:

Open path laser technology
Directly measures greenhouse gas emissions from grazing livestock. Early results show that this technology can accurately measure methane emissions from livestock in small paddocks. Further testing will be conducted in commercial scale paddocks.

Open path infra-red technology
Involves sending beams of infra-red light across paddocks containing grazing animals to analyse the reflected light for gas concentrations. This project is underway, with testing of the infra-red technology to commence early in 2011.

Managing and measuring emissions from manure

Gas recorders are being used to assess the amount of methane and ammonia released from manure stockpiles. Ammonia can be a precursor for nitrous oxide emissions and comes from animal urine and manure. Early results confirm that ammonia emissions from manure stockpiles are carried by wind to adjoining land where it may become a source of nitrous oxide emissions. More effective management of manure stockpiles may reduce methane and
nitrous oxide emissions. The RELRP is examining the effectiveness of two manure management practices;manure stockpile aeration and composting and urease inhibitors.

Manure stockpile aeration and composting
Both aeration and composting may reduce the amount of methane that is produced from manure stockpiles. Researchers are refining appropriate methods and analysing the methane reduction potential of both practices.

Urease inhibitors
Researchers are examining ways to reduce nitrous oxide emissions from manure by using urease inhibitors on
feedlot manure stockpiles. Urease inhibitors are chemical additives that stop urea (found in animal urine and
manure) converting to nitrous oxide. Early results show that applying urease inhibitors decreases the rate at which
nitrous oxide is emitted from manure.

Adapting rumen function

A diverse group of microbes in an animal’s rumen create energy through food digestion, releasing methane as
a by-product. The RELRP is looking at a number of ways to reduce methane production in the rumen by changing the way it operates. Methods being trialed include:

• animal breeding,
• biological controls,
• dietary supplements and feeding new forage plants.

Animal breeding
Researchers are investigating whether livestock can be bred as low methane emitters without compromising
production. High and low methane emitting cattle and sheep sires have been identified through the RELRP. The offspring of these sires are being assessed for their methane production. Rumen samples from these animals are also being analysed to identify the best indicators for measuring methane production in the rumen.

Biological control
Three biological control methods are being examined for their ability to reduce methane production from livestock. The first uses viruses to attack the microbes which produce methane; the second uses specialised proteins to target methane producing microbes; and the third uses other microbes (methanotrophs) to break down the methane produced in the rumen into other substances.

Dietary supplements and feed alternatives
A range of dietary supplements and feed alternatives are being trialed to assess whether they can reduce methane emissions from livestock. Supplements being considered include oils, fats, tannins, probiotics, nitrates, enzymes, marine algae and Australian native vegetation. Laboratory experiments have shown that some dietary oil and fat supplements can reduce methane emissions. Analysis using on-farm research has indicated that certain oil and fat supplements can reduce emissions by around 10 per cent in Victorian dairy systems. Early research shows that the methane inhibitor bromochloromethane reduces methane levels by up to 91 per cent in goats. While this technology will not be used under commercial conditions, it does provide evidence on how the rumen adapts to conditions where methane production is stopped completely. This information is important when developing future techniques that minimise methane production without affecting animal productivity.

New forage plants
Several alternative plant forages such as broccoli leaves and some Australian natives (tar bush, the golden wreath wattle and a number of salt bush species) have been shown to reduce methane emissions in laboratory experiments. Further research is planned to confirm these results under field conditions.

Mapping rumen microbiology
In order to assess the effectiveness of dietary changes on methane production, researchers are examining the complex microbiology of the rumen. This project has successfully developed a sound method to calculate the effect of such interventions on the rumen microbe population that creates methane.

Communicating research outcomes
To aid in the communication and extension of the RELRP’s research findings, five national demonstration sites are being developed. These are located at:

• University of New England, Armidale, NSW
• CSIRO Lansdown Research Station near Townsville, Qld
• University of Western Australia, Pingelly, WA
• Demo-dairy near Terang, Vic
• Department of Primary Industries Victoria, Hamilton, Vic.

Producers and industry stakeholders will be engaged through a number of forums and training workshops held on each demonstration site.

Partnerships
Research presented in this fact sheet is a result of partnerships between:

• Australian Wool Innovation
• CSIRO
• Dairy Australia
• Department of Agriculture, Fisheries and Forestry
• Department of Primary Industries Victoria
• Meat and Livestock Australia
• Sheep CRC
• South Australia Research and Development Institute
• University of Melbourne
• University of New England
• University of Queensland
• University of Western Australia
• University of Wollongong

About the Climate Change Research Program
The Climate Change Research Program is part of Australia’s Farming Future, the Australian Government’s climate change initiative for primary industries. The program funds research projects and on-farm demonstrations to help prepare Australia’s primary industries for climate change. Research focuses on reducing greenhouse gas pollution, improving soil management and climate change adaptation. The program is providing practical management solutions to farmers and industries. The Department of Agriculture, Fisheries and Forestry manages the Climate Change Research Program.

Acknowledgement
Information contained in this fact sheet was obtained from a research progress report provided by Meat and Livestock Australia, including input from the research partners listed.

Further information
For further information on the Climate Change Research Program or any of the funded projects please contact the Australia’s Farming Future hotline: 1800 638 746 or visit the website.

1. For further information on carbon offsets

2. Intergovernmental Panel on Climate Change (1995). Second Assessment Report Working Group I: The Science of Climate Change. Cambridge University Press.