By: Tina Casey
Cow farts are emerging as a major source of the greenhouse gas methane, but scientists in Australia may be on to a simple way to nip that in the bud. Preliminary studies are showing that feeding “algae cakes” to cows results in a significant reduction in their methane emissions.
As reported in The Australian, a team of researchers at James Cook University anticipates a sustainable quadruple whammy from the new bovine diet: algae absorbs more carbon dioxide than other plants, it can be grown as a natural water cleanser for fish farms, it can be harvested as a biofuel crop, and the leftover “cake” produces an anti-methane effect on cattle.
Algae Diet Cuts Greenhouse Gasses
The James Cook researchers note that the world’s domesticated cattle population accounts for up to 20% of methane emissions related to human activity, so in terms of greenhouse gas emissions, cow farts are no small potatoes. In developing countries cattle can account for an even larger proportion of greenhouse gas emissions. The issue is particularly significant in tropic zones, where the deterioration of pasture in the winter months results in poor fodder, which in turn leads to an increase in methane emissions. The theory behind using algae is that cows can digest it more easily, because it contains more starch and less cellulose than conventional fodder.
The “Beef and Reef” Algae Connection
Along with cutting methane emissions from cows, the researchers hope to protect the Inner Great Barrier Reef from excess nitrogen and phosphorus by promoting sustainable bioremediation at fish farms and other aquaculture operations (bioremediation uses plants to absorb pollutants rather than chemicals). Some aquaculturists resist bioremediation because it leaves them with massive quantities of biomass to dispose of. The widespread use of algae as cattle fodder could turn this liability into a profit center. To that end, the researchers are testing their cows on two species of green tide algae, Cladophora coelothrix and Chaetomorpha indicia, which were selected for their superior performance in bioremediation.
Other Methane Solutions
The livestock emissions issue is particularly acute in New Zealand, where methane from sheep and cows accounts for about half the country’s greenhouse gas emissions. Researchers there are exploring an anti-methane vaccine. Meanwhile, a team in Ireland has found that fish oil can be an effective anti-methane fodder additive.
Image: Cow by foxypar4 on flickr.com.