Influencing natural animal processes to reduce methane output
June 24, 2021
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Intervening in the natural animal processes that are occurring throughout enteric methane production is one strategy to reduce emission.
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The five strategies are: reduce the amount of fermentation, redirect hydrogen, eliminate methanogens, block methanogenesis and utilize digital technologies
Influencing natural animal processes to reduce methane output
Methane emission reduction is a heavily investigated category, particularly at different stages that occur in ruminant animal methane production. At Cargill, we’re researching the multitude of potential solutions, including one strategy in particular – intervening in the natural animal processes that occur throughout enteric methane production. Below are five critical areas of investigation.
1.) Reduce the amount of – or change nature of – fermentable substrate
The production of methane is a fermentation process that occurs naturally during the process of digestion. Increasing the rate of fermentation decreases methane production and leaves more energy for the animal. Diluting fermentable matter can also play a role in decreasing methane production.
It’s possible to formulate feed to reduce fermentable substrate and inhibit the creation of methane in the rumen. For example:
- Switching to a high starch/sugar diet: Increasing sugar and starches can help to speed up digestion, which decreases the rate of fermentation.
- Lipid feeding: Diluting fermentable matter with fat can decrease methane production.
- Probiotics: Can enhance gut microbiome and enhance digestion.
- Ionophores: Increase propionate (which utilizes hydrogen) production to decrease hydrogen available for methane production in the rumen.
2.) Redirect hydrogen to another process
Microbial fermentation, the process that creates methane in the cow’s stomach, requires hydrogen to take place. If we redirect the hydrogen to be absorbed by another chemical reaction, then (theoretically) less methane would be produced. There are several theories under investigation on which additives to include in feed that can provide the desired outcome:
- Sulfate Reducers: In theory, by adding sulfate to the diet, rumen microbes will produce hydrogen sulfides which use hydrogen.
- Nitrate Reducers: When added to the diet, nitrates have the potential to be converted to nitrite and then ammonia, which absorbs hydrogen in the process.
- Fumarate Reducers: When added to the diet, they have the potential to convert hydrogen into propionate which in turn uses up existing hydrogen.
3.) Eliminate methanogens
Methanogens are the methane-producing bacterium that live in the livestock’s gut (or rumen) that turn carbon dioxide to methane. By reducing the number of methanogens available in the rumen, we can potentially reduce the amount of methane released from the animal.
Essential oils and plant extracts are among the most investigated category in methane mitigation. So far, they have shown strong results in vitro (in lab) systems (but as you can learn here , that can be deceiving), and have shown limited effectiveness in short-term in vivo (in animal) studies.
4.) Block the process of methanogenesis
Methanogenesis is the formation of methane by methanogens in the gut. Right now, the hottest trend to do so is introducing seaweed to the livestock diet.
The principle is based on a compound called bromoform that exists in seaweed. Bromoform was intensively tested in the 70’s as a methane reducer.
You can read more about the use of seaweed-based feed ingredients and the latest pros and cons here.
5.) Disruptive technologies
AgTech is investing in the latest technology to reduce methane emission. One solution that has sparked interest is livestock wearables. For example, technology to convert methane when it is expired from the mouth of livestock.
The advantage? Wearables show no drastic impact on animal health, welfare, feed intake, production, or behavior.