American Agriculturist Logo

How much methane does a cow burp?

Respiration chambers at Cornell University may provide some clues.

Chris Torres, Editor, American Agriculturist

May 14, 2024

4 Min Read
Two men observe a Holstein cow in a respiration chamber
RESPIRATION CHAMBER: Joe McFadden, associate professor of dairy cattle biology and animal science at Cornell University, talks about the climate-controlled respiration chambers with a visitor during a recent ribbon-cutting for the $2 million project. Photos courtesy of Cornell University

According to the EPA, a single cow produces anywhere from 154 to 264 pounds of methane gas per year. Methane is considered a much more potent greenhouse gas than carbon dioxide, hence the reason many plant-based alternatives to beef and dairy have hit the market.

But a lot of things can affect how much methane a cow can belch out. Four climate-controlled respiration chambers recently installed at Cornell University may soon provide some answers.

“It comes down to effectively testing the efficacy and safety of feed additives, and other technologies that reduce methane production by the cow, but also identifying sensor technologies that accurately quantify changes in methane emissions,” says Joseph McFadden, associate professor of dairy cattle biology and animal science at Cornell University. “And the only way you really can do that is using a system that allows us to fully quantify GHG emissions from a cow.”

The four chambers — which cost $2 million — are stainless steel with windows on all sides, each having a single stanchion that can hold one cow at a time. Along with monitoring feed and water intake, they are designed to monitor oxygen consumption, and methane, carbon dioxide and hydrogen emissions in real time, taking measurements every two to 10 minutes.

Measuring gas exchange is key to understanding overall cow energy use. For example, cows lose, on average, between 6% and 7% of the energy they consume to methane gas produced during digestion of carbohydrates.

A group touring a cow methane measurement facility

To get a balanced accounting of a cow’s energetics, researchers must estimate heat loss, which can’t be directly measured. They do that, in large part, by measuring the amount of energy from food that is used up by gases, digestion, urine and feces, metabolism, tissue, and milk. They can apply this data to indirectly calculate heat loss.

Researchers can then consider how effectively different diets and feed additives may optimize meat and milk production and animal health, and minimize greenhouse gas emissions and nutrient waste.

The chambers are also climate-controlled, meaning researchers can monitor and influence temperature and humidity.

“So, we can try our best to mimic environments that are specific to a certain region of the country, for example, and we can also monitor the gas emissions,” McFadden says. “And so the gas emissions are monitored in real time, and we are monitoring oxygen to monitor how much it's consumed by an animal.”

McFadden says research using the chambers will focus first on two things: figuring out ways to reduce enteric methane emissions, and improving how to monitor those reductions.

Other technologies such as headbox systems are already used to monitor methane emissions. But McFadden says they are not able to quantify total emissions over a day in a controlled environment. Using the chambers, he says, may provide clues to help improve their accuracy.

One study already underway is evaluating the chamber system relative to already existing GreenFeed gas sensors, which are used on many dairies. McFadden says the goal is to develop correction factors to help make the GreenFeed sensors more accurate because they are portable and can be used in many operations.

The system will also evaluate alternative dairy feeds. He says the university has gotten support from the state of California to study the effects of bromoform in seaweed to see if it can reduce methane emissions from a cow’s diet.

While the chambers will first measure methane, carbon dioxide and hydrogen, McFadden says the goal is to add capabilities to measure nitrous oxide and ammonia.

He notes respiration chambers used to exist across the U.S. In fact, USDA built several respiration chambers in the 1950s and ’60s, helping researchers learn more about ruminant energy use and nutrition. But the systems were slowly decommissioned because of retiring faculty and outdated technologies. They were also expensive to maintain, he says.

The chambers will also be used to improve Cornell’s nutritional modeling software, called the Cornell Net Carbohydrate and Protein System, which is used in formulating diets for about 70% of lactating cows in North America. The model allows a nutritionist or farmer to input feed ingredients to formulate a diet specific to the cows, feeds and conditions, and the program can predict milk yield.

Cargill and Balchem provided financial support for the project. New York state and Genesee Valley Regional Market Authority also provided financial support.

Information from an April 18 article published by the Cornell College of Agriculture and Life Sciences was used in this article.

Read more about:


About the Author(s)

Chris Torres

Editor, American Agriculturist

Chris Torres, editor of American Agriculturist, previously worked at Lancaster Farming, where he started in 2006 as a staff writer and later became regional editor. Torres is a seven-time winner of the Keystone Press Awards, handed out by the Pennsylvania Press Association, and he is a Pennsylvania State University graduate.

Torres says he wants American Agriculturist to be farmers' "go-to product, continuing the legacy and high standard (former American Agriculturist editor) John Vogel has set." Torres succeeds Vogel, who retired after 47 years with Farm Progress and its related publications.

"The news business is a challenging job," Torres says. "It makes you think outside your small box, and you have to formulate what the reader wants to see from the overall product. It's rewarding to see a nice product in the end."

Torres' family is based in Lebanon County, Pa. His wife grew up on a small farm in Berks County, Pa., where they raised corn, soybeans, feeder cattle and more. Torres and his wife are parents to three young boys.

Subscribe to receive top agriculture news
Be informed daily with these free e-newsletters

You May Also Like