The burp of a grazing cow might seem silly to the uninitiated. But for those working toward more climate-friendly agriculture, it’s a serious topic of interest.
There are about 90 million cows on dairy farms in the U.S. alone, and each of them burps out methane as they digest grasses in their specialized ruminant stomachs. Since methane is a greenhouse gas that can be 87 times more potent than carbon dioxide, all these bovine belches can collectively have a big impact on the climate.
But it turns out that the ocean might have a solution to this problem. Adding tiny amounts of certain types of seaweed or algae to a ruminant animal’s feed has been shown to keep the methane-generating bacteria in their gut to a minimum.
A lot of the work to bring this concept from the ocean to the farm is taking place here in New York. And some of this work focuses on other ruminant animals, too.
Symbrosia, a company working on a red seaweed-based feed additive, teamed up in 2020 with what was then Z-Farms of Dutchess County to do some testing on sheep.
They reported weight gain and other good health indicators for sheep that were fed on the seaweed additive, and up to a 77% reduction in methane from those sheep. Several New York institutions are also partnering on a major project with Maine’s Bigelow Laboratory for Ocean Sciences to develop methane-reducing feed additives from algae. “The idea behind this project is trying to build upon where the red seaweed started,” says Nichole Price, a benthic marine ecologist with Bigelow who is leading the project.
Bigelow is a major biorepository for marine microalgae, and so there are many types of algae they can cultivate that may produce compounds that are active in reducing methane. Price says they aim “to screen microalgae species of interest for production of those compounds, then to take it a step further and see if we can make a correct formulation to integrate seamlessly into conventional farm operations.”
A major partner with Bigelow on this project is the W. H. Miner Agricultural Research Institute in Northeastern New York, where animal feeding trials are taking place. “We have a wide-ranging group of experts that allows us to evaluate the whole life cycle of a potential algae feed additive in dairy cows and how it might impact methane emissions,” says Sarah Morrison, a research scientist with the Miner Institute overseeing their role in the project.
Bigelow’s New York partnership also includes biological assessments at Clarkson University in collaboration with Cornell Cooperative Extension, supply chain and socioeconomic analysis at Syracuse University, and the development of gas sensing devices on ear tags at Lelantos, a small engineering company with ties to Columbia University.
Cornell’s College of Agricultural Life Sciences also has its own moonshot research program focused on developing methane-reducing feed additives made from red seaweed. Joseph McFadden, a dairy cattle biology professor who is leading that effort, has written about some of the major hurdles that stand between theory and practical application in agriculture. Those hurdles include long-term evidence that the additives are safe for the animal and the people who consume its milk or meat, scaling up cultivation of seaweed or algae to levels needed for widespread use (cows eat a lot!), and the short shelf life of the plant or its derivative compounds.
U.S. Rep. Nick Langworthy of New York will tell you that another big hurdle is the years-long approval process required by the U.S. Food and Drug Administration (FDA). Langworthy is leading a bipartisan cohort of U.S. representatives that have introduced the Innovative Feed Enhancement and Economic Development, or FEED, Act of 2025. The legislation aims to reduce approval times for feed additives used in agriculture, including those designed to reduce methane, by shifting regulation of these additives to fall within the FDA’s Food Additive Petition process.
While there is still a long way to go with bringing the big idea of methane-reducing feed additives into practice, all these efforts represent some real progress toward making the concept a reality.
