When the researchers fed beef steers varying amounts of red seaweed and tracked them over 21 weeks, they found that methane emissions dropped by up to 80%.
Livestock alone are responsible for roughly 14.5% of emissions, the majority of which is methane gas.
This methane arises in the stomachs of cows and their ruminant relatives before being belched out into the air.
Particularly promising is the red seaweed Asparagopsis taxiformis, which has unusually high amounts of bromoform in its cells.
When the steers were eating more fiber, the seaweed was relatively less effective at reducing methane emissions.
Overall, the steers that received the lower and higher amounts of seaweed slashed their methane emissions by 45% and 68%, respectively.
“We have to make sure that we have that balance where animals don't even know that it's there,” he said. »