Identification of novel anti-methanogenic pasture and freshwater and algae feed supplements

The University of Adelaide

  • Project code: PRO-016745

  • Project stage: Current

  • Project start date: Sunday, April 16, 2023

  • Project completion date: Monday, September 9, 2024

  • National Priority: NCO - National Challenges and Opportunities - M


The National Farmers’ Federation 2030 Roadmap envisages Australian agriculture trending towards carbon neutrality by 2030. Achieving this goal will require innovative research to reduce methane emissions from ruminants. To address ‘Objective 4: Methane Abatement’, we propose to apply a multidisciplinary approach which harnesses the resources and expertise across SARDI Livestock, Pasture and Aquaculture Research Divisions to investigate the methane-reducing potential of legume pastures and freshwater plants/algae. Identification of pasture germplasm that can be adopted at-scale, or new supplements from freshwater species, will complement existing Asparagopsis-derived Bromoform supplementation to ruminants in intensive feedlot environments


Our approach has three pillars:

  1. assessment of the saponin profile and resulting anti-methanogenic potential within germplasm from three pasture species, Lucerne, burr medic and spotted medic,
  2. characterisation of in vitro methane-emission profiles of selected freshwater plants/ algae and assessment of appropriate concentrations for optimal methane reduction efficacy, and
  3. in vitro screening using abattoir-derived sheep rumen fluid, rather than canular-derived rumen fluid, allowing assessment across breeds and livestock age categories

Our approach will develop an innovative ‘Anti-methanogenic Assessment Platform’ (AAP) for realistic assessment of the methane-reduction potential of existing, widely adapted pasture species and comparison against efficacy of methane reduction from supplementary feeding with freshwater plants/algae. Following the selection and intensive screening of the different species, we will conduct a comprehensive economic analysis to determine the cost-benefit of methane reduction feeding and supplementation strategies which could be validated on-farm, and subsequently developed into extension and adoption opportunities for the livestock industry.  


National Rural Issues

Research Organisation

The University of Adelaide

Objective Summary

Recent research has demonstrated significant reductions in methane emission from a number of marine and freshwater plant and algae species. The majority of these trials have been conducted in cattle, either from canular or abattoir derived rumen fluid (in vitro) or animals in the field (in vivo). These studies have demonstrated differences in methane emission responses depending on animal age and breed. Given these differences and the paucity of comparative sheep studies, we propose to undertake an intensive in vitro screening project to identify and quantify a wide range of pasture and freshwater plants and algae as potential methane-reducing feed supplements suitable for sheep.


Project outcomes are:

  1. Identify pasture and freshwater plants and algae species suitable to reduce methane emissions on-farm by 20 – 30%
  2. Identity saponin profiles in pasture species to be used as markers for identification of methane reducing pasture genotypes
  3. Refine harvesting and processing techniques to optimise the methane reducing properties
  4. Identify age and breed within in vitro methane emissions profiles using rumen fluid collected from Finisher lambs, mature animals, and sheep of different breeds

Extension pathways and capabilities outcomes:

  1. Determine the on-farm applicability, economic feasibility, and potential risk to establish, harvest and process pasture freshwater plants and algae species
  2. Engage with producers to develop collaborative opportunities for extension and adoption opportunities
  3. Provide post-graduate training opportunities (Honours level) & encourage retention of young researchers in the agricultural industry, and
  4. Support the career development/retention for early and mid-career researchers in the agricultural industry