Low-Carbon Livestock Management Methods

Overview

Over 60% of livestock emissions – the largest contributor to the agriculture sector’s greenhouse-gas output – stem from enteric fermentation. This is a natural part of the digestive process of ruminant animals such as cattle, sheep and goats. During digestion, microbes in the digestive tract break down food and produce methane as a by-product. This is problematic because methane is a powerful greenhouse gas. It has a shorter half-life than carbon dioxide, but traps 84 times more heat than CO2 in the first two decades after it is released.

Ruminants play a sizeable role in our food system: they supply 51% of protein from livestock, of which two-thirds is from dairy and one-third from meat, according to the UN Food and Agricultural Organization.

Source: IEA, BloombergNEF.

Emission targets on the agriculture sector are rare – all the more so for goals specific to livestock. However, there are exceptions: New Zealand aims to reduce methane emissions from biological sources (biogenic methane) by 10% below 2017 levels by 2030 and 24-47% by 2050. The target is a range to reflect the uncertainty surrounding the actual reduction required to meet the 1.5-degree temperature goal and future technological developments, according to the government. And it should be achievable if current improvements in emission intensity of meat and milk production continue.

Impact

Global emissions from livestock management rose 15% over 2000-2017. This growth was primarily driven by increased enteric fermentation in middle-income countries (notably China), with this process accounting for nearly two-thirds of global livestock emissions. Wealth and population growth have boosted demand for animal products, helping to raise enteric emissions in non-Annex I parties by 23% over that period. This compares with a 12% reduction in Annex I countries where demand for beef has stalled and production efficiency has been improved.

A range of mitigation strategies is available to reduce emissions or increase production efficiency, at varying levels of development and with varying levels of potential to reduce different gases (table below). Note that a given strategy may be able to reduce a given greenhouse gas but has a side effect of increasing another: for example, a decrease in enteric methane emissions may lead to an increase in emissions from applied manure.

Source: Grossi, G., Goglio, P., Vitali, A. and Williams, A.G., ‘Livestock and climate change: Impact of livestock on climate and mitigation strategies’, Animal Frontiers, 9:1, January 2019. Note: N2O = nitrous oxide.

With regard to enteric fermentation, strategies include enhancing forage quality meaning pastures with less fiber and higher soluble carbohydrates, thereby reducing methane production. This can be improved through plant breeding, using different grass types or grazing on less mature pastures. Another example is feed additives (eg, electron receptors or chemical inhibitors): some of the most widely available types could reduce emissions by 10-15%, while newer products with more mitigation potential are being piloted. However, some would need to be added daily to feedstuffs, which could be a challenge for animals that roam free and are mostly fed on grass, and the impact of such products on overall animal health has yet to be fully determined.

On livestock management: genetic selection has the highest mitigation potential for methane. While it may not necessarily reduce the greenhouse-gas output from livestock overall, it should improve the ratio of such output per animal to slow emission growth. Another strategy to reduce emissions (and potentially boost profitability) would be to lower the number of unproductive animals on a farm. Improving ‘stocking rates’ can be combined with feed or breeding approaches so that the number of livestock kept in a given space may be reduced without reducing production volumes.

Opportunity

The most common policy types in this area are mandates and financial incentives. For example, as part of the Canadian Agricultural Partnership, the AgriScience program offers grants of up to C$5 million over five years or a cost-sharing arrangement for projects that promote sustainable growth and emission reduction. Further support is available from the provincial and territorial governments. A new tool was launched by trade body Beef + Lamb New Zealand Genetics in 2019 enabling sheep breeders to select animals with genetically lower methane emissions. The tool was developed through a collaboration between government and industry research institutes.

Alternatively, financial incentive programs could be adapted to implement obligations that would aid emission reduction. As an example, members of the European Parliament’s environment committee voted in 2019 to restrict subsidy payments to livestock farms if they exceed a stocking density of 0.7 livestock units per hectare of utilized agricultural area, as a way to incentivize farmers to shift to less intensive farming. The EU (including the U.K.) had an average stocking density in 2016 of 0.8 livestock units per hectare of utilized agricultural area, and this can be much higher, with 13 of the 28 countries exceeding the 0.7 threshold that year.

The agriculture sector is already governed by an extensive range of regulations, suggesting that these could be extended to achieve climate-related objectives. For example, the U.K. Committee on Climate Change has recommended that the Clean Air Strategy could be modified to require feed additives that reduce methane emissions from livestock and U.K. feed producers could be mandated to incorporate methane-inhibiting additives in compound feed. At least in the U.K., there are relatively few feed manufacturers, reducing monitoring costs for the government. However, such a strategy would only be effective for markets where a sizeable share of animals are confined to a given area and feed is brought to them, rather than the livestock grazing or seeking feed in open pasture, etc.

One of the reasons why enteric emissions have stabilized in developed nations is stagnating demand for red meat, especially beef. Government with ambitions to decarbonize the agriculture sector will therefore need to consider how to influence consumer behavior regarding food (and food waste). For example, there is growing consumption of, and investment in, plant-based and cultured meat alternatives. These products have the potential to displace a significant share of meat consumption, if market strategies, pricing and consumer attitudes evolve. This could help to reduce the agriculture sector’s greenhouse-gas output, given their lower emission intensity.

Source

BloombergNEF. Extracted from G20 Policy Scoreboard report published on February 1, 2021 and from Advancing Agriculture: Decoding Carbon Emissions insight published on August 6, 2020. Learn more about BloombergNEF solutions   or   find out how to become a BloombergNEF client.