Burp-free cow feed drives seaweed science at USC

by Janelle Kirkland

A puffy pink seaweed that can stop cows from burping out methane is being primed for mass farming by USC researchers.

As food production has a significant carbon footprint, and the methane produced by ruminants, such as cows, sheep and goats, are a sizeable contributor to that footprint, the ability to greatly reduce or remove this emissions source is a potential game-changer.

In August this year, Professor of Marine Science Nick Paul, USC’s Seaweed Research Group leader, featured in the third episode of ABC documentary ‘Fight for Planet A: Our Climate Challenge’. He was interviewed by host Craig Reucassel about his research and the enormous role that seaweed can play in reducing the cattle emissions that contribute to climate change.

The particular seaweed species, called Asparagopsis, grows prolifically off the Queensland Coast, and was the only seaweed found to have the effect in a study five years ago led by CSIRO.

“Seaweed is something that cows are known to eat. They will actually wander down to the beach and have a bit of a nibble,” said Professor Paul.

“When added to cow feed at less than two percent of the dry matter, this particular seaweed completely knocks out methane production. It contains chemicals that reduce the microbes in the cows’ stomachs that cause them to burp when they eat grass.

“If we can feed every cow in Australia, we could cut the country’s greenhouse gas emissions by up to 10 percent. This new feed supplement can complement a range of other ways that the red meat industry is reducing its carbon footprint," he said.

The USC team is working at the Bribie Island Research Centre in Moreton Bay to learn more about how to grow the seaweed, with the goal of informing a scale-up of production that could supplement cow feed on a national or even global scale.

“Seaweed offers so many benefits, as a food source for people, as an immunity booster, for restoring the biodiversity of our coastlines, and storing carbon from the atmosphere. Seaweed aquaculture and industry in Australia can also provide many opportunities for jobs and economic growth and recovery. Our research team is excited to be working to understand and realise the enormous potential that seaweed can offer to the economy, the environment and communities everywhere,” he said.