Replacing 2% of cows’ feed with an Australian seaweed ended the cows’ methane production.
In a five-year study, Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) discovered that the seaweed, Asparagopsis taxiformis inhibited 98.9%of methane production by cattle, after 72 hours.
However, the pink seaweed is not abundant, and only grows in temperate tropical waters.
It grows prolifically along the Queensland coast, but scientists are now trying to devise a way to make it a farm crop that can be widely harvested, so that its methane-busting properties can be fully exploited.
If researchers can achieve that, there’s a national — and potentially global — market waiting for an Asparagopsis feed additive for cattle.
As a greenhouse gas, methane has a high heat-trapping potential, it but only lasts 10 years in the atmosphere.
Therefore it does not accumulate like carbon dioxide or nitrous oxide greenhouses gases.
Methane only increases if the number of ruminants emitting it increases.
Nevertheless, it has been estimated if all the cattle in Australia ate the seaweed, the country could cut its greenhouse gas emissions by 10%.
In general, cattle produce less methane if they are on a grain diet, compared to a grass diet, because methane is a by-product of digestion of high-fibre roughage.
Scientists found that chemicals in Asparagopsis diminished the microbes in cows’ stomachs that produce methane.
Scientists also aim to maximise the concentration of the effective chemical, so that a lesser amount of seaweed can have the desired effect.
When added to cow feed at less than 2% (on a dry matter basis), it stopped methane production. It isn’t hard to get cattle to eat it. Where it grows on the Queensland coast of Australia, cattle seek it out and eat it without encouragement.
According to CSIRO, the idea for their research started with farmers like Joe Dorgan in Canada, who noticed that his cattle in a paddock by the sea were more productive, and this was attributed to the storm-tossed seaweed they were eating.
Researchers investigated and found seaweed improves cow health and growth, but also reduces their methane production.
The study of feed additives to reduce belched methane is in full swing globally, and some of these additives are quite effective.
DSM, a Dutch company, continues to file for authorisations around the world for its methane-reducing feed additive, 3-NOP, (3-nitrooxypropanol). It reduces methane production by around 30%, by suppressing an enzyme in the cow’s stomach.
In July, 3-NOP was submitted for EU feed additive approval, for dairy cows.