An Australian team from James Cook University has identified a type of red alga, Asparagopsis taxiformis, which reduced methane production by 99% when tested on artificial cow stomachs in laboratory conditions. This species of seaweed is effective because it produces a compound called bromoform (CHBr3) that reacts with vitamin B12 in ruminant stomachs to block methane production. Trials are ongoing in Queensland.
With FAO reporting that livestock are responsible for 44% of global methane emissions, animal agriculture is becoming increasingly acknowledged as a major environmental problem. However scientists tackling this problem have found that adding a sprinkle of seaweed to cow feed has the potential to massively reduce ruminant emissions.
Initial practical experiments have been positive: pilot tests have shown that by feeding Asparagopsis to sheep at 2% of their diet, they produce between 50-70% less emissions. The fact that cows also respond well to the seaweed is significant given that they are responsible for 65% of livestock emissions. This discovery may also contribute food productivity as seaweed-eating cattle have been documented to be healthier and larger as less energy is wasted dealing with methane.
The global seaweed farming industry is not yet at sufficient scale to meet these requirements but its already positive growth may be further accelerated by this potential future demand.
Although not being a quick fix, this discovery has the potential to make significant emission reductions on a global scale if adequate sustainable sources of seaweed can be found.