Methane is responsible for about 30% of global warming, making it one of the most powerful greenhouse gases, with a warming potential 80 times that of carbon dioxide.

Cattle are the largest emitters of methane, with a single cow producing between 70 and 120 kg of methane annually. Overall, greenhouse gas emissions from livestock are estimated to contribute 14.5% to the global total. Methane is produced in ruminant cattle primarily when they burp, due to a type of microbe in their digestive system called methanogen.

While humans rely on animal protein, particularly from cows, methane emissions from livestock remain an unavoidable problem. Consequently, scientists are actively seeking effective ways to reduce these emissions in livestock farming. It is worth noting that pasture-raised cattle tend to release more methane than those raised in barns, primarily due to their access to larger quantities of grass.

A research group from the University of California has been working to find solutions to this crisis. They discovered that adding a substance derived from seaweed can reduce methane emissions from cattle by 40%, making cattle farming more sustainable without negatively impacting the health or weight of the animals. The researchers published their findings in the journal Proceedings of the National Academy of Sciences on December 2, 2024.

Between Pastures and Barns

Cattle raised in barns typically spend only about three months there, while those that graze in pastures do so for most of their lives. Methane gas is emitted in both cases. One proposed solution is to add supplements to cattle feed to mitigate methane emissions; however, maintaining control over the diet of pasture-grazing cattle poses a challenge. The researchers aimed to find an effective solution for this issue.

Supplements

In a study, twenty-four bulls were tested on a farm where the researchers divided them into two groups. One group received seaweed supplements for ten weeks, while the other did not. The results showed that methane emissions from the first group were reduced by 40%.

The study authors believe this method could help reduce methane emissions from both pasture-grazing cattle and those raised in controlled environments. This approach would promote more sustainable cattle farming while still meeting human demands for animal protein.