Methane Emissions Reduction

Today, livestock are estimated to contribute about 14.5%¹ of global human-originated greenhouse gas (GHG) emissions and approximately 3% of U.S. emissions are attributed to methane produced during enteric fermentation². While many industries bear responsibility for their climate contributions, agriculture is in a unique position to drive meaningful change.

Enteric fermentation is the unique digestive process of animals with multiple stomach compartments. The natural process produces methane, a potent GHG, which is released by the animal into the atmosphere most notably through burping.

Growing methane emission concerns are putting pressure on producers to implement solutions to reduce their impact. To support farmer efforts to reduce livestock emissions, Cargill deploys a holistic approach to methane mitigation with a focus on three areas: best farm management practices, improved animal productivity through feed and nutrition, and rumen modifiers.

Best Farm Management to Increase Production

Addressing methane emissions starts with defining a farm’s efficiency – or the total amount of methane emissions compared to the output (milk or beef). Studies show that increasing animal and farm efficiency globally is one of the most effective methane mitigation strategies. By supporting the herd’s productivity, enteric methane production per kg of milk or beef is reduced, and fewer animals are needed to produce a larger amount of animal protein product.

Yet, farm efficiency varies greatly across the globe, requiring a focus on helping farmers increase production, while optimizing inputs and herd management. Cargill works closely with farmers to improve herd health and efficiency by deploying best practices to support sustainable production and help reduce methane intensity. Depending on farmer goals, best management practices can include increasing the average age of lactating dairy cows, addressing animal stress, and using technology, like Dairy Enteligen, to breed cattle to reach their full potential.

Improved Animal Productivity Through Feed and Nutrition

Ruminant dietary intervention is one of the most investigated categories in methane mitigation and is a critical area of innovation to build a sustainable food system. Cattle diets impact how feed is digested and used in the rumen; therefore, focusing on nutrition and feed management can have great environmental impact. Dietary intervention studies focus on:

• What farmers feed their cattle. Focusing on what is fed to ruminants is important because correctly balanced, high-quality feeds are more digestible and can improve production. Studies have found that feed additives, such as prebiotics, essential oils, yeasts and antioxidants, can boost intake, digestion, health and overall productivity.
• Cattle feed preparation. How feed is prepared can influence animal productivity. For example, finer grain that is cracked and ground, and smaller feed particle sizes are easier on digestion.
• How feed is digested and used. Feed’s nutritional value varies and offering the right nutrition relies on studying complex variables, like how cattle digest and use feed.

Innovation: Rumen Modifiers

Feed additives like rumen modifiers can directly influence enteric fermentation and ultimately, methane reduction. Some additives can work directly to inhibit the growth or function of methanogens, the methane producing microbes. Others can limit how much hydrogen is available in the rumen to lessen methane production. For example:

• Essential Oils. Essential oils have been studied rigorously in vitro (in lab) and in vivo (in animal) to determine their impact on eliminating methanogens. Our unpublished research has found in vivo results show little or no effect on methane reduction, whereas in vitro shows strong methane reduction. In vivo trials are critical to securing evidence validating their methane reduction effect.
• Nitrate, sulfate and fumarate. Researchers have found that modifiers, like nitrate, sulfate and fumarate are plausible solutions to redirecting hydrogen, which is a key component to synthesize methane.
• Modifiers to reduce hydrogen. Some modifiers show promise in promoting the creation of different fermentation products to reduce the hydrogen available for methane synthesis.
• Seaweed. Researchers are also looking into ways in which to block methanogenesis altogether. Bromoform-enriched seaweed is a solution that is often cited as a way to inhibit methanogenesis.

The Future of Methane Reduction

Today, farmers need trusted advisors who can help assess animal needs, advise within the context of their operation and provide new solutions and innovations. This requires a holistic approach to methane mitigation – meaning looking beyond manipulating feed and altering the natural rumen processes.

As a trusted partner and advocate for farmers, Cargill knows that an implementable solution for dairy and beef producers requires research and financial investment by dairy and beef producers, whether that be through nutrition or other avenues. With farmer livelihood at the center of our work, we foster a holistic approach to methane mitigation. Our goal is to accelerate progress and change while helping farmers to nourish the world safely, responsibly and sustainably.

Sources
¹ Tackling Climate Change through Livestock: A global assessment of emissions and mitigation opportunities (fao.org)
² Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2018 – Main Text (epa.gov)