Improving animal nitrogen use efficiency and reducing nitrous oxide emissions on dairy farms

Whole farm systems analysis from the WFSAM project

The study examined two theoretical approaches for improving nitrogen use efficiency (NUE) in dairy cows to reduce associated nitrous oxide emissions for three dairying regions of south-eastern Australia:

  1. Maintaining the same level of N exported in milk from a reduced N intake; 
  2. Increasing the amount of N exported in milk for the same level of dietary N intake.

Treatments covered four supplementary feed N concentrations combined with four milk N concentrations.

The results showed that both options can improve NUE and reduced nitrous oxide emissions, though significantly greater abatement in nitrous oxide emissions can be achieved by improving animal NUE via reductions in the amount of N in supplementary feed, as opposed to increasing N exported in milk.

Primary researcher


Christie KM, Rawnsley RP, Harrison MT, Eckard RJ (2013). Using a modelling approach to evaluate two options for improving animal nitrogen use efficiency and reducing nitrous oxide emissions on dairy farms in southern Australia. Animal Production Science, 54, 1960-1970,

More information

Research Theme


Project Status


Project Leadership

Dr Christie Ho
  • Dr Christie Ho
  • Senior Research Scientist
  • Agriculture Victoria

Richard Eckard
  • Professor Richard Eckard
  • Director
  • Primary Industries Climate Challenges Centre

Richard Rawnsley
  • Dr Richard Rawnsley
  • Senior Research Scientist
  • Tasmanian Institute of Agriculture

Fact Sheet

Project Team

  • Dr Brendan Cullen
    University of Melbourne
  • Dr Matthew Harrison
    Tasmanian Institute of Agriculture
  • Dr Alexandria Sinnett
    Agriculture Victoria
  • Karen Christie
    Tasmanian Institute of Agriculture
  • Natalie Doran-Browne
    University of Melbourne

Funding Organisations

  • Agriculture Victoria
  • Australian Wool Innovation Limited
  • Dairy Australia
  • Department of Agriculture and Water Resources
  • Meat and Livestock Australia
  • Tasmanian Institute of Agriculture
  • University of Melbourne

Collaborating Organisations

  • Agriculture Victoria
  • Tasmanian Institute of Agriculture