The Problem

Livestock farming – a livelihood, source of nutrients and contributor to global warming

Methane

The methane emitted by ruminant animals makes up approximately 6% of global greenhouse gas emissions. This may not seem like a significant amount, but the potent warming effect of methane means that finding a solution to reduce the methane produced by livestock can make a real difference in achieving the goal of limiting global warming to 1.5oC.

Because methane breaks down in the atmosphere after about a decade, it does not continue to accumulate in the way that CO2 does. This means that acting now to cut methane emissions is the most effective tool we have to make a difference to global warming in the near term.

Methane

Source: Jackson et al. 2020, ERL (Fig. 1), UNFAO Enteric Methane Report

In New Zealand alone, methane emissions are our biggest opportunity to impact total greenhouse gas emissions.

New Zealand's Greenhouse Gas Emissions.

Note: Percentages in graph may not add up to 100 due to rounding.

How animals make methane

There are over 1 billion cattle globally, emitting methane through a natural process called enteric fermentation. Global production of methane from ruminant animals equates to 200 mega tons per annum.

Enteric fermentation is the process ruminants use to break down natural fibres such as grass, and convert them into energy to produce nutritious meat and milk products. During this process, opportunistic organisms called methanogens, which live in a cow’s large stomach, the rumen, create methane (CH₄) that is released in cattle burps.

Source: Processes of the methane production in ruminants (https://www.sciencenews.org.nz/sites/default/files/sn-2015/112825_cow_digestion_730)

Methane globally

A lot of progress has been made with feed additives that provide effective methane reduction.  However, because they need to be included with every mouthful of food to be highly effective, feed additives are not a viable solution for pasture-grazed livestock – which is the dominant way of farming in much of the world.

Livestock farming provides both a livelihood and an accessible source of vital high-quality nutrients to millions of people around the world but it also contributes to global warming.

Over 150 countries globally have signed up to the Global Methane Pledge, a commitment to reduce emissions of methane by 30% by 2030. About 40% of the world’s methane comes from ruminant animals.

If we can deliver a solution to these hard-to-address emissions, the effects will be game changing, and will enable sustainable livestock farming.We need a solution that will save both farmers and the planet.