Methane emissions from livestock, such as sheep and cows, are a major contributor to greenhouse gas emissions in Australia and a critical environmental challenge for the agriculture sector.
Studies show that livestock is responsible for 70 per cent of all methane emissions derived from Australian agriculture.
A team of researchers at the Tasmanian Institute of Agriculture (TIA), Dr Apeh Omede, Dr Jay Kocharunchitt and recently graduated honours student, Ms Luorui Li, are exploring new types of natural feed additives to see if they can reduce methane emissions from livestock without affecting their health, growth or production.
They've conducted laboratory research that mimics the fermentation process in a sheep's stomach and so far, there's been positive signs that the feed additives are working.
The research focussed on adding two natural bioactive compounds to a model sheep stomach in the laboratory - probiotic bacteria and glycoprotein. The effects of these two compounds were tested across multiple doses and incubation times.
Lead researcher, Dr Apeh Omede, said the goal is to reduce emissions without compromising health and productivity of livestock.
"There's an emerging focus that natural bioactive compounds are a sustainable alternative to synthetic feed additives," Dr Omede said.
"While direct methane output has not yet been investigated, there are several strong indicators of anti-methane emission activity that has emerged.
"One of the key findings was a significant increase in propionate which is a fatty acid produced in livestock stomachs, while there was a reduction in the ratio of acetate, another fatty acid, to propionate. This shift is widely associated with lower methane production and positive effect on productivity."
The study also observed enhanced total volatile fatty acids, which suggests more efficient livestock stomach fermentation overall.
"It's likely there can be methane mitigation through these natural compounds, and they can also support productivity," Dr Omede said.
"The research highlights the untapped potential of naturally derived compounds to improve livestock sustainability. As climate pressures on agriculture intensify, such innovations could play a key role in reducing methane."
Dr Omede hopes to continue the research with animal trials to validate the laboratory findings.
The funding for the project was provided through the JM Roberts Charitable Trust, which was established in 2003 by the late John Roberts, a Tasmanian orchardist and farmer, to support environmental sustainability, agricultural innovation, and the education of young people about the importance of landcare.
Since 2020, the JM Roberts Charitable Trust has generously provided $20,000 of seed funding to TIA each year, supporting a total of 12 projects.
