Highlights:

The global livestock sector contributes a significant share to anthropogenic GHG emissions, but it can also deliver a significant share of the necessary mitigation effort. The need to reduce the sector’s emissions and its environmental footprint has indeed become ever more pressing in view of its continuing expansion to ensure food security and feed a growing, richer and more urbanized world population.

Livestock: a significant contributor to climate change

With emissions estimated at 7.1 gigatonnes CO2 -eq per annum, representing 14.5 percent of human-induced GHG emissions, the livestock sector plays an important role in climate change. Beef and cattle milk production account for the majority of emissions, respectively contributing 41 and 20 percent of the sector’s emissions. While pig meat and poultry meat and eggs contribute respectively 9 percent and 8 percent to the sector’s emissions.

Feed production and processing, and enteric fermentation from ruminants are the two main sources of emissions, representing 45 and 39 percent of sector emissions, respectively. Manure storage and processing represent 10 percent. The remainder is attributable to the processing and transportation of animal products. Included in feed production, the expansion of pasture and feed crops into forests accounts for about 9 percent of the sector’s emissions.

Cutting across categories, the consumption of fossil fuel along the sector supply chains accounts for about 20 percent of sector emissions.

Important reductions in emissions within reach

Technologies and practices that help reduce emissions exist but are not widely used. Their adoption and use by the bulk of the world’s producers can result in significant reductions in emissions. Emission intensities (emissions per unit of animal product) vary greatly between production units, even within similar production systems. Different farming practices and supply chain management explain this variability. Within the gap between the production units with the lowest emission intensities and those with the highest emission intensities, lies an important potential for mitigation.

A 30 percent reduction of GHG emissions would be possible, for example, if producers in a given system, region and climate adopted the technologies and practice currently used by the 10 percent of producers with the lowest emission intensity.

Efficient practices key to reducing emissions

There is a direct link between GHG emission intensities and the efficiency with which producers use natural resources. For livestock production systems, nitrous oxide (N2O), methane (CH 4 ) and carbon dioxide (CO2 ) emissions, the three main GHG emitted by the sector, are losses of nitrogen (N), energy and organic matter that undermine efficiency and productivity.

Possible interventions to reduce emissions are thus, to a large extent, based on technologies and practices that improve production efficiency at animal and herd levels. They include the use of better quality feed and feed balancing to lower enteric and manure emissions. Improved breeding and animal health help to shrink the herd overhead (i.e. unproductive part of the herd) and related emissions. Manure management practices that ensure the recovery and recycling of nutrients and energy contained in manure and improvements in energy use efficiency along supply chains can further contribute to mitigation. Sourcing low emission intensity inputs (feed and energy in particular) is a further option.

Additional practices with promising mitigation potential

Grassland carbon sequestration could significantly offset emissions, with global estimates of about 0.6 gigatonnes CO 2-eq per year. However, affordable methods for quantifying sequestration, as well as a better understanding of institutional needs and economic viability of this option, are required before it can be implemented at scale.

A range of promising technologies such as feeding additives, vaccines and genetic selection methods have a strong potential to reduce emissions but require further development and/or longer time frames to be viable mitigation options.

Mitigation interventions to contribute to development

Practices and technologies that reduce emissions can often simultaneously increase productivity, thereby contributing to food security and economic development.

Mitigation potential across the board

The mitigation potential can be achieved within existing systems; this means that the potential can be achieved as a result of improving practices rather than changing production systems (i.e. shifting from grazing to mixed or from backyard to industrial). The major mitigation potential lies in ruminant systems operating at low productivity (e.g. in South Asia, Latin America and the Caribbean, and Africa). Part of the mitigation potential can be achieved through practices related to better feeding, animal health and herd management.

Sizeable reductions could also be achieved in intermediate pork and poultry production systems, in particular, in East and Southeast Asia which rely on purchased, high emission intensity inputs, but do not operate at high efficiency levels.

Enabling environments crucial for unleashing mitigation potential

Supportive policies, adequate institutional and incentive frameworks and more pro-active governance are needed to fulfil the sector’s mitigation potential. Awareness-raising and extension are important first steps towards the adoption of better technologies and practices. These require investments in communication activities, demonstration farms, farmer field schools, farmer networks and training programmes.

Sector organizations can play an important role in raising awareness among producers and disseminating best practices and mitigation success stories. While many of the mitigation practices are likely to be profitable in the mid-term, public policies should ensure that farmers can face initial investment and possible risks. This is particularly important in least affluent countries, where limited access to credit and risk adverse strategies will prevent the uptake of novel options requiring upfront investment. The provision of microfinance schemes can be effective to support the adoption of new technologies and practices by small-scale farmers. Where the adoption of technologies and practices are costly for farmers in the short or medium term, but provide large public mitigation benefits, abatement subsidies should be envisaged.

Public and private sector policies also have a crucial role to play in supporting research and development to improve the applicability and affordability of existing technologies and practices, and to provide new solutions for mitigation. Significant additional research is also needed to assess the costs and benefits of mitigation options in practice.

Efficiency-based mitigation strategies will not always result in a reduction of emissions, especially where production grows rapidly. While keeping rural development and food security issues in consideration, complementary measures may be needed to ensure that overall emissions are curbed. Further, safeguards should be in place to avoid the potential negative side-effects of efficiency gains, such as animal diseases, poor welfare, and soil and water pollution.

International efforts should be pursued to ensure that mitigation commitments, both within and outside the United Nations Framework Convention on Climate Change (UNFCCC), are strengthened to provide stronger incentives to mitigate livestock sector emissions and ensure that efforts are balanced through the different sectors of the economy.

In least affluent countries where the mitigation potential is important, it is crucial to set up sector development strategies that serve both mitigation and development objectives. Such strategies may well condition the wider adoption of mitigation practices.

Need for collective, concerted and global action

Recent years have seen interesting and promising initiatives by both the public and private sectors to address sustainability issues. Complementary multistakeholder action is required to design and implement cost-effective and equitable mitigation strategies, and to set up the necessary supporting policy and institutional frameworks. It is only by involving all sector stakeholders (private and public sector, civil society, research and academia, and international organizations) that solutions can be developed that address the sector’s diversity and complexity. Climate change is a global issue and livestock supply chains are increasingly internationally connected. To be effective and fair, mitigation actions also need to be global.