Methane Emission From Livestock and its Mitigation Strategies

India is the third-largest greenhouse gases emitter in the worldwith a total share of 6.76%,As per to 20^th Livestock Census, India had the most livestock population in the world, numbering 535.78 million and this releases a significant amount of methane, a gas with a warming potential 20 times greater than that of carbon dioxide. India is thought to have the world’s largest livestock population, which produces methane, which can considerably increase global temperatures. India’s emissions of methane from livestock currently stands at about 13% of global emissions from livestock. According to reports livestock accounts for 78% of India’s total 24 million tonnes of methane emissions.

With an annual global contribution of 14.5%, the livestock sector is a significant source of anthropogenic (caused by humans) methane emission. According to estimates, over a 20-year period, the Indian livestock industry could increase surface temperatures by up to 0.69 millikelvin, or about 14% of the total increase brought on by the livestock industry worldwide. The impact on climate change is global in result, so the negative impact due to livestock emission is not restricted to India. Methane emissions can be reduced by using better livestock rearing techniques, such as using the right feed types and increasing livestock productivity.

Methane levels in the atmosphere are mostly influenced by the growth of the livestock population. However, lowering methane levels may be possible through improved livestock productivity, population stabilization, better feed, and manure use. Methane emissions in the context of India are concerning because two major sources, livestock and paddy fields, are expanding quickly. Both sources have ties to the food and economic security of India.

Sources of Methane Emission

Comparing other agricultural subsectors, such as rice cultivation and open burning of crop residue, Indian livestock contributes the most methane emissions. The production of rice and enteric fermentation in ruminant animals are the two main biogenic sources of CH₄. Animal production-related greenhouse gas emissions from the agricultural sector include CH₄ emissions from domestic animals directly, CH₄ and N₂O emissions from manure and grazed lands, and N₂O emissions from soils. In India, there is an urgent need to lower livestock-related GHG emissions. Methane emissions are influenced by animal diet composition and the ratio of various feeds, including soluble residue, hemicellulose, and cellulose content. GHG emissions from animals come from two sources:

(a)During digestion: In herbivores, methane is created as a by-product of “enteric fermentation,” an enzymatic digestion process developed by symbiotic microorganisms living in the rumen media and used to break down carbohydrates into simple molecules for bloodstream absorption.

(b) From animal waste: Organic substances like proteins and carbohydrates can be found in animal excrement. Anaerobic bacteria convert the carbon skeleton in animal manure to methane during the process of decomposition in damp, oxygen-free settings. Nitrogen can also be found in animal excrement in the form of a number of complicated molecules. Animal waste is subjected to microbial nitrification and denitrification processes, which produce nitrous oxide that is released into the atmosphere.Due to the large population of livestock in India, even though the emission rate per animal is much lower than in developed nations, the total annual CH₄ emission from enteric fermentation and animal wastes is approximately 9–10 Tg.

Mitigation Strategies for Methane Emission

• The management of India’s cattle population may become challenging under the current governmental framework. The sacred cow policy in India prohibits the slaughter of cows. “The government may consider this issue from an economic and ecological perspective in addition to an ideological one.

• By increasing the productivity of its livestock, which would lead to a decrease in the number of animals raised, India could partially reduce its methane emissions from animal husbandry. India should address this issue without using techniques that have proven problematic in Western nations, such as the excessive use of antibiotics and hormones. “Even without such interventions, there is ample scope to improve milk yields through selective breeding and balanced feed,” says the World Health Organization. India’s milk yields continue to be about five times lower than the best-performing nations, like the USA.

• The National Livestock Mission, which includes, among other things, Breed Improvement and Balanced Rationing, is being carried out by the Department of Animal Husbandry and Dairy. Methane emissions from livestock can be decreased by feeding them premium-quality balanced rations.

• Reduced feed intake per unit of output methods are the most efficient means of reducing methane emissions from cattle. GHG emissions can be decreased by using fermented manures like biogas slurry in place of unfermented farmyard manure. To keep greenhouse gas emissions at the desired level, balanced farming methods must be implemented.

• Methane emissions could be decreased via ruminant cattle population reduction, breeding controls, and waste management. The most efficient method for reducing methane emissions is to decrease the number of ruminant animals. Increased cattle production might make it possible to use fewer animals to produce an equivalent amount of output while producing enteric methane at a lower rate. Some breeding management techniques that could be utilised to limit methanogenesis include genetic selection and breeding of low methane emitters. Additionally, manure management practises like shortening the duration of manure storage and assisting anaerobic digesters may greatly reduce CH₄ emissions.

• The most promising method for reducing methane emissions from cattle is to increase the productivity and efficiency of livestock production through enhanced nutrition. enhancing pastures, processing feed, adding more concentrates to the ration, etc. By increasing concentrates in ruminant feeds, the roughage concentrate ratio can be changed, lowering methane emissions. However, increasing concentrates increases the formation of lactic acid, which may result in ruminal acidosis. Increasing the quality of the pasture is another efficient method for lowering enteric methane emissions. Leguminous forages increase digestibility, so mixed pastures like alfalfa-grass pastures have been shown to reduce emissions by 25% compared to grass-only pastures. The same goes for feed processing methods like ensilaging, chaffing, and grinding, which have been shown to reduce emissions by 10%.

Conclusion

Climate change poses a serious danger to the viability of the livestock production system, where mitigation and adaptation measures are crucial for lowering livestock-related GHG emissions. In addition to helping to meet international obligations, reducing enteric methane emissions in ruminants will also improve animal performance and the effectiveness of energy use. If we want to maintain livestock production in the face of changing climatic conditions, both these mitigation and adaptation strategies must work together. Any attempt to lessen the effects of climate change must adopt a multidisciplinary strategy, bringing in fields like housing, health, and animal nutrition.

The uncertainties surrounding the nature and scope of the impact on the output level should likely be addressed soon away so that government officials and policymakers can develop the necessary measures. Significant research and development are required to boost the accessibility and affordability of efficient mitigation methods. Therefore, to adapt to the scenario of a changing climate, further study on appropriate breeding programs, utilisation of the genetic potential of native breeds, genetic conflict between adaptation and production traits, and simulation models are warranted.

India today unquestionably leads the world in milk production. It is already the biggest producer and will continue to outpace its rivals in the years to come. However, from the perspective of climate change, this growth cannot and should not avoid scrutiny. Animal husbandry is the foundation of milk production, and raising cattle, buffalos, and goats is a significant source of the extremely potent greenhouse gas methane.

Anuj Kumar¹,Amit Kumar², D K Singh³, Ahmad Fahim⁴ and Rohit Kumar⁵

¹Ph.D. Research Scholar, ²Professor and Head, ³Professor, ⁴Assistant Professor, Department of Livestock Production Management, ⁵Ph.D. Research Scholar, Department of Animal Nutrition, College of Veterinary and Animal Sciences, Sardar Vallabhbhai Patel  University of Agriculture and Technology, Meerut, 250 110, India

Corresponding author:

Email- *drvetanuj@gmail.com