Is seaweed the answer to India’s other ‘cow problem?’
Scientists in Australia claim to have discovered a way to reduce the methane in cow farts and belches, which are considered a major source of the greenhouse gas, especially in India.science Updated: Oct 06, 2017 18:11 IST
It’s the other cow problem that keeps some bovine scientists up at night. What to do about methane-rich cow farts and belches?
Methane is a potent greenhouse gas and in the long term (about 100 years) almost 25 times as potent as carbon dioxide in warming the planet.
Now, researchers at the James Cook University in Queensland, Australia, have found that feeding cows small amounts of seaweed may reduce the content of methane in their farts and belches.
A recent report showed that in 2016 India’s greenhouse gas emissions rose by 4.7%. Greenhouse gases include not just carbon dioxide but methane, nitrous oxide and fluorinated gases, which constitute 28% of all greenhouse gas (GHG) emissions, and in India they contribute to over 30% of GHG emissions.
Increase in these gases was also one of the major causes for GHG rising in India last year. Methane is the most important non-CO2 greenhouse gas. The biggest emitter of methane is cattle, which contribute to almost a quarter of global methane emissions.
Some researchers believe the contribution of cows to methane production is overestimated. The International Panel for Climate Change (IPCC) suggested that it was 46 kg per animal per year. Other studies peg the number in the range of 20-33 kg per animal. But with over 300 million cattle in India, the largest number for any country, the problem takes on grave proportions.
It started off a surprise discovery by an Australian farmer in 2005, his cows that fed on seaweed seemed healthier and more productive.Six years later, the farmer sold off his farm to start selling seaweed enriched cow feed.
When scientists did an experiment feeding cows seaweed, methane production reduced by up to 50% but it depended on the amount of seaweed fed to the cow. Feeding cows too much seaweed, they reasoned, would adversely affect bovine digestion.
In the latest set of experiments, researchers have found that feeding cows a particular species of red algae called Asparagopsis taxiformis could bring down methane production by over 99% in lab studies.
The results are yet to be independently verified and tested in the field, but even if they are successful it is unclear how so much of this particular algae will be sourced for the over 300 million cattle in India.