Approximately 65% of Australian agricultural greenhouse gas emissions are attributed to methane emissions. As majority of Australian sheep and beef cattle are grazed (~ 95%), there is clear potential for exploiting the anti-methanogenic potential within existing, widely adapted pasture species such as Lucernes and medics. There is also an as-yet untapped opportunity to explore new sources of anti-methanogenic compounds such as freshwater plants and algae, which may have commercial potential as supplements, and which have the potential to be grown with relative ease in shallow ponds.

We have identified a research gap in the exploration of anti-methanogenic compounds on sheep methane emissions. We also see an opportunity to better understand the effect of breed and age on methane-production and how this phenotype may affect the efficacy of anti-methanogenic compounds.

In this project, we propose to develop and deploy a ‘Anti-methanogenic Assessment Platform (AAP)’ to identify and characterise methane-reducing properties within diverse germplasm of Lucerne and medic pasture species and freshwater plant and algae species. Pasture species shown to be high in saponins will be intensively screened using an in vitro rumen approach to characterise gas production and emissions, analysing differences in response to animal age and breed.

The information from this project will be used to (1) inform future pasture breeding efforts, (2) assess the potential for commercialisation of supplements derived from freshwater or algae species, and (3) undertake cost-benefit analysis of on-farm feeding and supplementation strategies.