Seaweed could hold the key to cutting greenhouse gas emissions, one cow burp at a time.
New research carried out in north Queensland could drastically reduce the impact the agricultural industry has on the global environment.
Professor of aquaculture at James Cook University in Townsville, Rocky De Nys, has been working with the CSIRO studying the effects seaweed can have on cow’s methane production.
They discovered adding a small amount of dried seaweed to a cow’s diet can reduce the amount of methane a cow produces by up to 99 per cent.
“We started with 20 species [of seaweed] and we very quickly narrowed that down to one really stand out species of red seaweed,” Professor De Nys said.
The species of seaweed is called asparagopsis taxiformis, and JCU researchers have been actively collecting it off the coast of Queensland.
“We had an inkling that we would get some success from this species, but the scale or the amount of success and reduction we saw was very surprising,” he said.
Professor De Nys said methane gas was the biggest component of greenhouse gas emissions from the agriculture industry, and the findings could help alleviate climate change.
He also added that the vast majority of methane comes from the cow’s burp rather than the gas from the other end of the cow.
Researchers use an artificial cow’s stomach to test species
To test the effectiveness of each individual seaweed species, the CSIRO created an artificial rumen.
“You create the conditions you would see in a cow’s stomach, in a bottle,” Professor De Nys explained.
“You do that by collecting a little bit of the cow’s stomach to start with.
“They get a little bit of material from inside the rumen that has all those microbes, and then they add them to different grasses or substrates, and then you add a little bit of seaweed to that.
“As they ferment … just like you would see in a compost bin or somewhere else, the gas is created and it creates pressure.”
He said by measuring and sampling the pressure of the gas, they were able to determine how much methane gas was in it.
“Once you establish that works then you can go to whole animals,” he said.
“We have results already with whole sheep; we know that if asparagopsis is fed to sheep at 2 per cent of their diet, they produce between 50 and 70 percent less methane over a 72-day period continuously, so there is already a well-established precedent.”
The thought of cows chomping down on fresh seaweed in outback Australia may be entertaining thought, however, Professor De Nys said they intend to use dried seaweed instead.
“When the seaweed is harvested it is dried, and it can be added as a sprinkle essentially to the diet, just as you would add a mixture of herbs and spices to the chicken,” he said.
Mr De Nys said trials would be underway at the CSIRO Lansdown facility near Townsville until mid-next year to analyse the effects seaweed could have on cattle production.
“We will feed animals and measure more carefully how the seaweed affects both the production of methane and any increase in weight gain in those animals,” he said.
‘Getting enough seaweed to feed millions of cows’
Research scientist with Agriculture and CSIRO, Rob Kinley had been heavily involved in the research project.
“All sectors are trying to be responsible and reduce their contribution to climate change, which in many instances relates to reducing their contributions to greenhouse gas emissions,” he said.
“Agriculture stands to be one of the first to make dramatic reductions if we can get this to market.”
However, while their research was promising, Mr Kinley was concerned about access to seaweed.
“That is the number one barrier — getting enough seaweed to feed to millions of cows.”
“Wild harvesting isn’t going to do it because it’s far too expensive and the recourses aren’t enough, so we need to get partners on board who can produce the seaweed in a cultivation process.
“Whether that be in South-East Asia where they are already farming millions of tonnes of seaweed, or beginning a new industry somewhere through the southern or western side of Australia.”
Although, according to Mr Kinley, time was less critical than money in this case.
“Money will decide how quickly we can move … the sooner we have more money to move forward with the research, the sooner we will be able to get it out,” he said.
“Three years isn’t outside the realm if we can get enough support to move with it.”