Canadian researchers Rob Kinley and Alan Fredeen have found that seaweed not only helped improve the cows’ health and growth, but also reduced their methane production by about 20%.
This and other lines of evidence led Kinley, who by then had moved to CSIRO, to team up with other CSIRO scientists and marine algae specialists at James Cook University to test a wide range of seaweeds.
They tested 20 seaweed species and found that they reduce methane production in test-tube samples from cow stomachs by anything from zero to 50%. But to do this required high amounts of seaweed (20% by weight of the sample) which was likely to present digestion issues for animals.
But when the researchers tested a particular type of seaweed collected from Queensland’s coastal waters, they thought their instruments were broken and ran the tests again. It turns out that Asparagopsis taxiformis reduces methane production by more than 99% in the lab. And unlike other seaweeds where the effect diminishes at low doses, this species works at doses of less than 2%.
Source: Michael Battaglia, CSIRO blog, October 14, 2016.