Anti-Methanogenic Feed Supplement: Harit Dhara

News: Indian Council of Agricultural Research (ICAR) has developed an anti-Methanogenic feed supplement ‘Harit Dhara’ (HD). This supplement can cut down cattle methane emissions by 17-20% and can also result in higher milk production.

What is Harit Dhara?

  • It has been made from tannin-rich plant-based sources. Tropical plants containing tannins, bitter and astringent chemical compounds, are known to suppress or remove protozoa from the rumen.
  • It decreases the population of protozoa microbes in the rumen, responsible for hydrogen production and making it available to the archaea (structure similar to bacteria) for reduction of CO2 to methane.
  • Fermentation after using this supplement will help produce more propionic acid, which provides more energy for lactose (milk sugar) production and body weight gain.
  • Reduces methane production: An average lactating cow or buffalo in India emits around 200 litres of methane per day, while it is 85-95 litres for young growing heifers and 20-25 litres for adult sheep. Feeding Harit Dhara can reduce these by a fifth.

Methane production within cattles:

  • Methane is produced by animals having rumen.
  • Rumen is the first of the four stomachs where the cattle eat plant material, cellulose, fibre, starch and sugars. These get fermented or broken down by microorganisms prior to further digestion and nutrient absorption.
  • Carbohydrate fermentation leads to production of CO2 and hydrogen. These are used by microbes (Archaea) present in the rumen to produce methane.
  • Methane’s global warming potential 25 times of carbon dioxide (CO2) over 100 years, makes it a more potent greenhouse gas. The 2019 Livestock Census showed India’s cattle population at 193.46 million, along with 109.85 million buffaloes, 148.88 million goats and 74.26 million sheep.
  • Belching cattle, buffaloes, sheep and goats in India emit an estimated 9.25 million tonnes (mt) to 14.2 mt of methane annually, out of a global total of 90 mt-plus from livestock.
  • Being largely fed on agricultural residues i.e wheat/paddy straw and maize, sorghum or bajra stover – ruminants in India tend to produce 50-100% higher methane than their industrialised country counterparts that are given more easily fermentable/digestible concentrates, silages and green fodder.