Background 1 2
The local breeds of cattle that are farmed in the developing world are well-adapted to their environments in terms of disease resistance, heat tolerance and low nutrition needs. However, productivity is low and the amount of GHG emissions produced per kilogram of milk and meat can be very high. Selecting more productive animals is one strategy that can enhance productivity and reduce emissions intensity. To this end, researchers have attempted to utilize natural genetic variations in cattle populations to breed reduced-emissions cattle, but results are inconclusive as yet.
Relationship to CSA
Cross-breeding programmes can deliver simultaneous adaptation, food security and mitigation benefits. Cross-bred cattle developed for the tropical grasslands of northern Australia demonstrate greater heat tolerance, disease resistance, fitness and reproductive traits compared with the breeds normally used. These strategies make use of locally adapted breeds that are tolerant to heat, poor nutrition as well as parasites and diseases; and they will become increasingly useful as the climate changes. Cross-breeding coupled with diet intensification can lead to substantial efficiency gains in livestock production and methane output. With widespread uptake, this would result in fewer but larger, more productive animals being kept, which would have positive consequences for methane production and land use.
Impacts and lessons learned
Switching to cross-bred cattle with higher milk production potential and higher body weights will result in modest reductions in the amount of methane produced per tonne of milk. But cross-bred animals produce more milk and meat and, as a result, fewer animals are required to meet demand. Thornton and Herrero (2010) 3 estimated the impacts of widespread adoption (29% by 2030) of cross-bred animals on meat production in the rangeland systems and dairy production in the mixed systems of the tropics. The larger animals produce more than double the amount of milk and meat, compared with local breeds. Using only local breeds to meet milk demands in 2030 would require 363 million bovines, and a further 173 million bovines would be required to meet meat demands. If 29% of those local breeds were replaced by crossbreds, this could be reduced to 308 million bovines for milk production and 145 million for meat. An intervention on this scale has a mitigation potential of about 6 Mt CO2 eq.
References
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1
Thornton PK, Herrero M. 2014. Climate change adaptation in mixed crop-livestock systems in developing countries. Global Food Security 3(2):99-107.
http://dx.doi.org/10.1016/j.gfs.2014.02.002 Mixed crop–livestock systems produce most of the world's milk and ruminant meat, and are particularly important for the livelihoods and food security of poor people in developing countries. These systems will bear the brunt of helping to satisfy the burgeoning demand for food from increasing populations, particularly in sub-Saharan Africa and South Asia, where rural poverty and hunger are already concentrated. The potential impacts of changes in climate and climate variability on these mixed systems are not that well understood, particularly as regards how the food security of vulnerable households may be affected. There are many ways in which the mixed systems may be able to adapt to climate change in the future, including via increased efficiencies of production that sometimes provide important mitigation co-benefits as well. But effective adaptation will require an enabling policy, technical, infrastructural and informational environment, and the development challenge is daunting. -
2
FAO. 2013a. Climate-Smart Agriculture: Sourcebook. Rome, Italy: Food and Agriculture Organization of the United Nations.
http://www.fao.org/3/a-i3325e.pdf Between now and 2050, the world’s population will increase by one-third. Most of these additional 2 billion people will live in developing countries. At the same time, more people will be living in cities. If current income and consumption growth trends continue, FAO estimates that agricultural production will have to increase by 60 percent by 2050 to satisfy the expected demands for food and feed. Agriculture must therefore transform itself if it is to feed a growing global population and provide the basis for economic growth and poverty reduction. Climate change will make this task more difficult under a business-as-usual scenario, due to adverse impacts on agriculture, requiring spiralling adaptation and related costs. -
3
Thornton PK, Herrero M. 2010. The potential for reduced methane and carbon dioxide emissions from livestock and pasture management in the tropics. PNAS 107(46):19667–19672.
http://dx.doi.org/10.1073/pnas.0912890107 We estimate the potential reductions in methane and carbon dioxide emissions from several livestock and pasture management options in the mixed and rangeland-based production systems in the tropics. The impacts of adoption of improved pastures, intensifying ruminant diets, changes in land-use practices, and changing breeds of large ruminants on the production of methane and carbon dioxide are calculated for two levels of adoption: complete adoption, to estimate the upper limit to reductions in these greenhouse gases (GHGs), and optimistic but plausible adoption rates taken from the literature, where these exist. Results are expressed both in GHG per ton of livestock product and in Gt CO2-eq. We estimate that the maximum mitigation potential of these options in the land-based livestock systems in the tropics amounts to approximately 7% of the global agricultural mitigation potential to 2030. Using historical adoption rates from the literature, the plausible mitigation potential of these options could contribute approximately 4% of global agricultural GHG mitigation. This could be worth on the order of $1.3 billion per year at a price of $20 per t CO2-eq. The household-level and sociocultural impacts of some of these options warrant further study, however, because livestock have multiple roles in tropical systems that often go far beyond their productive utility.