The majority of those emissions, around two-thirds, come from cattle, and the demand for beef

and dairy is continuing to increase.

One way to quickly reduce these potent levels in livestock is to stop methane from being

produced in their stomachs, and that comes down to what they eat.

I'm heading into the bush, inland from the Townsville port, to meet a leading authority

on what's being described as a game-changer for the global livestock industry. It's

a super-feed supplement made from seaweed.

The Australian research body FutureFeed has found a seaweed species unique to Australasia

called Asparagopsis, which could be the most viable solution for curbing methane emissions

in cattle and sheep.

I've come to a research station in Woodstock, northern Queensland.

Rob Kinley is FutureFeed's chief scientist.

Hi Rob, I'm Kate.

I'm Dr Rob Kinley, welcome to Landsdown. Want to take a look around?

Yeah, sounds good.

This is ground zero for the first beef study that was done using the seaweed. So in the

facilities that we're coming up to, we have some respiration chambers in there. And that's

where we can put the cattle in for 24 to 48 hours and measure their emissions around the

clock.

By simply adding dried amounts of Asparagopsis to cow feed, Rob and his team saw methane

levels dramatically drop.

It was unbelievable how potent this was. Then we moved on and on and on to where we are

standing here today, with a product that we can potentially take methane emissions more

than 90 per cent out of lot-fed animals, animals that get their feed mixed for them.

Once they do eat it, it interrupts the metabolism of a certain kind of microbe in the gut that

produces the methane.

Incorporating it into the feeding system is the trick. As long as the seaweed is of good

quality and that's where the cultivators come in.

Tiny gland cells in seaweed make and store the organic compound bromoform, that can block

carbon and hydrogen atoms from forming methane.

That's what US aquaculture startup CH4 Global is farming in South Australia, the bromoform.

So we're farmers, we're not actually harvesting from the wild. We're taking some wild material,

turning it into a large number of baby weedlings, putting those weedlings

out to sea and letting them grow.

From seedling to final processing takes between 45 and 60 days.

This is in the raw form, the dried seaweed. It's been from the hatchery, it's gone out

to sea and grown. We've harvested it, we've dried it and then we bring it in here to see

how much bromoform is in the actual seaweed samples.

A cow eats about 12 to 14 kilos of feed a day, we need to get about 50 grammes, 50 grammes

of seaweed in that mix of 12 to 14 kilos. So, if you had that vial filled up to the

line here, that's all that the cow would have to consume every day to wipe out the methane

in its stomach.

One challenge that needs to be overcome is how to ensure that cows grazing outside get

the right amount of seaweed in their diet, as you can't just spread it on the ground

and leave them to it.

A larger hurdle is scaling production in this nascent industry. CH4 Global wants to become

a commercial-scale supplier, but it would be the world's first.

We're ready to go to the market now, but not at the scale of the demand that exists out

there. We need to spend the next six months getting better at it, improving our trade

over the next six months, that will allow us to bring our cost of goods down, understand

our product inside and out, and then know how to hit that green button and do scale.

So go from your one hectare, 10 hectares to 100, 1,000 hectares.

Earlier this year, the company announced a world-first agreement to supply enough Asparagopsis

supplement for up to about 10,000 head of cattle. A promising start, but there are about

1.5 billion in the world. So we're just at the beginning of a long journey to methane-free

livestock.