How Improved Practices Could Reduce Livestock's Greenhouse Gas Footprint
Jan 11, 2018
According to recent estimates by the UN’s Food and Agricultural Organization (FAO), global livestock production accounts for just under 15 percent of all anthropogenic (human-sourced) greenhouse gas emissions. These emissions include carbon dioxide emissions from producing animal feed and clearing land for grazing, enteric emissions from the gastro-intestinal systems of ruminant animals such as cattle, buffalo, sheep, and goats, and methane and nitrous oxide generated from animal waste.
Some analyses, such as a 2014 report from the British think tank Chatham House, have insisted that reducing global demand for meat through regulation or imposing taxes on its consumption is a crucial step toward preventing catastrophic global warming and its consequences. However, such recommendations have not been widely embraced to date, either by environmental groups advocating a vigorous response to the threats of climate change or by national governments outlining their plans of action under the Paris Climate Accord, because of both social and economic problems that would be associated with adopting such an approach.
Even though meat and dairy products are often over-consumed in developed countries, governments in those countries are for the most part, reluctant to impose rules or taxes that would restrict their citizens’ choices and preferences in that area. That is not the case in developing countries, where lack of access to protein from animal sources is an ongoing problem. In its most severe form, kwashiorkor, in which lack of protein leads to severe malnutrition, is most prevalent among children in developing countries, and leads to wasting and lifetime health consequences, and causes as many as 6 million deaths per year worldwide. A low share of animal protein in one’s diet can also cause iron or zinc deficiency, as accessible protein from plant sources does not always contain these micronutrients.
Livestock production is also essential to supporting the livelihoods of millions of families around the world, especially in developing countries. According to the International Livestock Research Institute (ILRI) headquartered in Nairobi, Kenya, about 750 million people in developing countries rely primarily on livestock production, especially in arid or semi-arid rural regions where pastoral grazing of ruminant animals is the main viable economic activity.
Fortunately, there are many ways to change the way that livestock are raised that will reduce their greenhouse gas emissions overall. For example, a 2015 study by scientists at the University of Nebraska found that corn that has been partially processed before being fed to beef cattle can improve the grain’s digestibility, increasing feed efficiency and reducing resulting methane emissions. Adding vegetable oils such as crude soybean or linseed oil, or less expensively, corn byproduct feeds which retain some corn oil, to a cattle herd’s finishing diet can also reduce methane emissions.
At the farm level, beef and dairy producers can also add methane digesters to their operations, which can convert the methane otherwise emitted from the cattle’s manure into electricity which can be utilized on the farm or even fed back into the power grid. Although such equipment is expensive, cost-sharing assistance from federal or state programs can make them more affordable. The United States lags behind other major livestock producing nations, such as China and India, in adopting this technology. Other improvements in manure handling practices, such as covering stored manure with straw and composting, could also lead to reduced emissions.
Research is also underway at the University of Bristol in England that is developing technology that would allow producers to identify the emissions footprint of individual pasture-fed cattle, and thus cull their herds of poor performing animals.
At the corporate level, integrated hog and poultry firms are taking steps to reduce their greenhouse gas footprint. For example, in December 2016, Smithfield Foods, working with the Environmental Defense Fund, announced plans to scale back fertilizer application on grain produced to feed its hogs, and to install methane digesters at farms raising the company’s hogs under contract. In May 2017, Tyson Foods, working with the World Resources Institute, announced plans to look at ways to reduce emissions along its supply chain of turkey, broiler, hog, and cattle producers.
In South Africa, villagers in Kwazulu Natal province has switched from raising cattle to raising goats, which are both hardier in the face of drought stress and have a more modest greenhouse gas profile. These changes, sponsored under a project funded by the national and state government as well as Heifer International, are also beneficial to women farmers in the region, because goats are easier for them to manage than cattle.
Improvements in grazing practices, that can reduce soil carbon losses in grasslands and rangelands, can be adopted in both developed and developing countries. Rotational grazing practices, under which an area of grassland is intensely grazed for a short period and then left alone for a period to allow the grass plants to regrow, have been used successfully in the United States for decades, and has been introduced for use in Southern Africa in recent years as well.