Posts Agriculture, Climate, Environment, Food

Greenhouse gases in cow burps warm up the climate. To mitigate this effect, researchers at Luke study different feeding and breeding strategies to reduce the amount of methane emitted by cattle.

Year after year, the Earth has hit new record high levels of heat-trapping greenhouse gases in the atmosphere. To avoid the most destructive effects of a warming climate, emissions of greenhouse gases need to be cut rapidly and in all sectors of our societies. Even cows play a role in this effort.

Ruminants like cows have an impact on climate because they burp a lot of methane, a potent greenhouse gas. As there are over a billion cattle in the world, cutting their emissions could help slow down climate change substantially.

Scientists at the Finnish Natural Resources Institute (Luke) are interested in what controls methane production in cattle.

“Cows are very valuable creatures. They provide high-quality food and necessary work power especially in poorer countries,” says senior scientist Alireza Bayat from Luke.

“But we need to solve the methane problem.”

Cutting the emissions of cattle could help slow down climate change substantially, says Ali Bayat. Photo: Eetu Ahanen.

Nutritional interventions have potential

Cows burp out around 95% of all the methane they emit. The rest come out from the other end of the animal.

The reason behind these emissions are microbes. They live in specialized compartments in ruminants’ stomachs and allow their host to digest feed very efficiently. The climatic downside of this collaboration is that the microbes do their work in anaerobic conditions and produce methane as a byproduct.

Alireza Bayat and his colleagues study the effect of nutrition on these emissions.

“So far, nutritional interventions have been the most promising way to reduce emissions from ruminants. At Luke, we have tested strategies such as adding different fats and oils to the cows’ diets, and proven that they reduce methane emissions.”

Research is also ongoing on other kinds of feed additives that inhibit enzymes involved in methane production. Certain compounds have been found to reduce methane emissions from cattle by up to 60%, without adversely affecting the health and performance of the animals.

Bayat and his fellow researchers at Luke have also found that along with diet and microbes, individual properties of cows affect methane emissions.

“Our results do not let us make clear conclusions on a single most important factor in reducing the emissions,” Bayat describes.
“It’s a complex system that you can study from different angles. But we are a team – we complement each other.”

Nutrition plays an important role in how much methane cows emit. Photo: Outi Pihlman.

Special chambers make the research possible

The research is conducted at a special facility in Jokioinen, Finland, where Luke has four metabolic chambers. They allow studying dairy cows’ energy metabolism and methane emissions with a ‘gold standard’ technique.

“The chambers have been used to generate invaluable data for scientific purposes,” Bayat says.

“By using them we can measure the cows’ energy expenditure and methane production under different experimental conditions.”

The metabolic chambers have been utilized for example to examine the effect of antibiotics on methane emissions, and test different dietary strategies on cows that emit low or high amounts of methane.

“Thanks to their transparent view and friendly conditions, the chambers do not affect feed intake and milk yield of the cows,” Bayat explains. “To my knowledge Denmark is the only other Nordic country with a similar facility.”

Luke also does international collaboration on the topic. Luke’s research and empirical evidence from the chambers have contributed to improving scientific models that predict methane emissions from cattle in different regions and under different nutritional conditions.

Text: Antti Miettinen

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