What role do ruminants play in methane pollution?

Bill Gates has invested in a climate technology startup aimed at reducing methane emissions from cow burps.

Rumin8 is a startup that is developing a variety of dietary supplements for cows in order to reduce the amount of methane they emit into the atmosphere.
The supplement contains red seaweed, which is thought to significantly reduce methane output in cows.

Methane is a greenhouse gas that is also found in natural gas.
Methane comes from a variety of sources, including both human and natural sources.
Anthropogenic sources account for 60% of total global methane emissions.
Landfills, oil and gas systems, agricultural activities, coal mining, wastewater treatment, and certain industrial processes are all included.
The oil and gas industries are among the largest contributors to human-caused methane emissions.
These emissions are primarily caused by the combustion of fossil fuels, landfill decomposition, and agriculture.

Ruminant animals such as cows, sheep, goats, and buffaloes release this methane mainly through burping.
They have a special type of digestive system that allows them to break down and digest food that non-ruminant species would be unable to digest.
Ruminant stomachs have four compartments, one of which, the rumen, allows them to store partially digested food and ferment it.
The animals regurgitate this partially digested and fermented food, chewing it through again to complete the digestive process.
However, as grass and another vegetation ferment in the rumen, methane, a potent greenhouse gas, is produced.

Given the large number of cattle and sheep on dairy farms, these emissions add up to a significant volume.
The ruminant digestive system is estimated to be responsible for 27% of all methane emissions from human activity.

Methane is a major contributor to climate change, accounting for 30% of warming since preindustrial times, second only to carbon dioxide.
According to a UNEP report, methane is 80 times more potent at warming than carbon dioxide over a 20-year period.
It is also the main source of ground-level ozone, a colourless and highly irritating gas that forms just above the Earth’s surface.
According to a 2022 report, ground-level ozone exposure could cause 1 million premature deaths each year.
Several studies have found that the amount of methane in the atmosphere has increased dramatically in recent years.

Scientists have been working on making these animals more environmentally friendly and less gassy.
According to a 2021 study published in the journal PLUS ONE, adding seaweed to cow feed can reduce methane formation in their guts by more than 80%.
In addition, researchers are looking for gene-modifying techniques to reduce methane emissions in these animals.
Scientists in New Zealand announced last year that they had launched the world’s first genetic programme to address the challenge of climate change by breeding sheep that emit less methane.

GMI is an informal international partnership with members from 45 countries, including the United States and Canada.
Last year, India and Canada co-chaired the GMI leadership meeting, which was held virtually.
The forum was established to achieve global reductions in anthropogenic methane emissions through collaboration between developed and developing countries with transition economies.
The forum was founded in 2004, and India has been a member since its inception, serving as Vice-Chairman for the first time in the Steering Leadership alongside the United States.

Source: https://pubmed.ncbi.nlm.nih.gov/22444607/