Farmers and ranchers around the world face increased heatwaves, droughts and heavy rainfall, making it harder to grow livestock and crops. This means less financial security for farm families and, globally, bigger threats to people’s access to nutrition.
USDA Photo by Preston Keres
Methane, a super-pollutant greenhouse gas, worsens the weather impacts farmers are facing. And livestock farming itself is a major methane source, contributing about one-third of human-caused methane emissions. Helping farmers lower these emissions is essential for protecting our food systems and our communities.
The good news is that we have tools ready to go that can support reduced emissions from livestock farms so that we have access to the nutrition people need and the foods we love. These solutions can often also create benefits for farmers, like using methane as energy. But farmers need our help to get them implemented.
So, where does livestock methane come from, and what can we do about it? Read on for three exciting solutions.
Cow burps with less methane
As cows digest their food, they burp out methane (yes, it’s the burps, not the other end), and this, cumulatively, has a massive climate impact. Enteric emissions, or cow burps, account for 90% of livestock methane.
The good news is that this also presents an opportunity to lower those emissions, especially if we can provide a range of solutions that work for different farms. How we lower these emissions depends on factors like whether animals graze in a field or eat in a barn, as well as where in the world the farm is located.
If cows are kept in a barn, farmers can give them a supplement — think of it as a probiotic for cows — that reduces how much methane they burp. For these supplements to effectively lower methane, cows have to eat them at every meal, so they’re only practical for livestock that eat in a barn, not for those that graze in a field.
One such supplement, Bovaer, has been approved in more than 50 countries and can reduce enteric methane up to 30% — that’s huge! It’s a powder supplement that is added to livestock feed at every meal, just as we sprinkle cinnamon on our oatmeal or add protein powder to smoothies. Other promising supplements are in development.
Scientists are also working on enteric methane solutions, such as breeding livestock that naturally burp less methane, that work for grazing dairy cows and beef cattle.
More productive cows mean less methane
What cows eat and their health also have a direct link to methane emissions. Healthier, well fed cows produce milk and meat that has a lower methane footprint, also known as methane intensity.
In wealthy countries, cows are already highly productive. Like professional athletes, they have customized diet and nutrition plans built by professional nutritionists. This has led to highly efficient farming with low methane intensity. The essential next step for these farms is adopting additional practices and technologies — like the supplements discussed above — that lower enteric- and manure-related methane to reduce total, or absolute, emissions.
In lower- and middle-income countries, there’s often room to help farmers further optimize livestock productivity and lower methane intensity. This will almost always include improving the quality and quantity of feed available for livestock. Better feed helps animals produce more milk or meat. This in turn helps improve nutrition for families, supports farmer livelihoods and reduces methane intensity — what we call a triple-win solution.
There’s also room to help farmers enhance the health of their animals through better disease management. We can’t do our best work when we feel sick. The same goes for livestock.
For example, cows around the world can get mastitis, an infection in their udder. A dairy cow with mastitis is uncomfortable and produces less milk, all while emitting the same amount of methane. Scientists are studying both how to reduce these infections and the potential reduction in methane emissions from doing so.
Better manure management
Manure contributes the remaining 10% of livestock methane emissions. While manure storage is beneficial for water quality and can be used as a fertilizer, when manure is scraped from barns into large storage pits, microbes in it produce a lot of methane.
There are effective solutions ready to be used more widely, including covering manure storage lagoons and separating solids from liquids. Covered lagoons are often combined with flare systems that burn off methane gas or digesters that capture methane gas to use as energy. Solid-liquid separation lowers the amount of methane produced in storage and allows for more efficient recapture of nutrients to be used as fertilizer.
These solutions are often prohibitively expensive though, and farmers need financial support to adopt them. Manure solutions also can’t address methane alone; they must also be part of a holistic system that addresses other local impacts like air and water pollution.
For instance, digesters can easily cost a million dollars or more, requiring farmers to navigate complicated grants and financing. And the decision to build one should be made with local community engagement, and should also include additional treatment steps to manage unintended consequences, including ammonia, which forms a powerful pollutant, PM 2.5, that can be harmful to human health.
We can lower livestock methane emissions
Lowering methane emissions from livestock is a huge opportunity to alleviate some of the worst impacts of climate change within our lifetimes. While we know that livestock produce a lot of methane, we have ways to reduce it while also providing other economic and nutritional benefits.
But most farmers need supportive financing and policies to help them adopt existing solutions. We need to continue investing in helping farmers and investing in new solutions, too.
If we do this well, we don’t have to make a false choice between productive farms, a thriving planet and the food we love. We can have all three.