Livestock in the Global Food System

Globally, the term livestock refers to domesticated terrestrial and aquatic animals farmed by humans for a variety of goods and services—including meat, milk, eggs, fiber, and physical labor—across a diverse array of agricultural systems.

In the high-income nations, farmed animals are most often kept in intensive production systems that have negative consequences for the environment and for human and animal health. In alternative farming and traditional food systems elsewhere in the world, subsistence farmers and small-scale commercial farmers raise livestock in extensive production systems with fewer negative impacts.

As the world faces the challenge of bringing food production in line with planetary boundaries while addressing global hunger and confronting the climate crisis, it is imperative to rethink industrial models of livestock production and their continuing impacts on people, animals, and the environment.

WHAT IS LIVESTOCK FARMING?

Livestock farming includes supply chains related to the management, breeding, employment as labor, and slaughter of livestock animals. While the term most often refers to the species most commonly exploited for food and fiber, including cows, pigs, goats, and sheep, its full scope encompasses a wide diversity of species impacted by human use.

The United States Department of Agriculture (USDA) defines “livestock” more narrowly than common usage, including only hogs, sheep and lambs, cows and calves. Poultry raised for meat or eggs are excluded from the USDA definition, as are fish.

In the United States, most livestock farming is conducted intensively for commercial profit rather than for subsistence. The largest livestock industries are those raising chickens, cattle, turkeys, and pigs—9 billion chickens, 32 million cattle, 241 million turkeys, and 121 million pigs are slaughtered annually, with cattle the most lucrative at a production value of over $50 billion per year.

Livestock farming forms a foundational role in the diets of around 400 million subsistence farmers around the world. East and Southeast Asia produce by far the most livestock worldwide, specifically chickens and pigs. Latin America ranks second globally for livestock production, with cattle and chicken leading production roles. North America and Western Europe have similar production levels, although Western Europe produces more dairy and pork and less beef and chicken than North America. In South Asia, the most common livestock are buffalo, followed by dairy cattle. Sub-Saharan Africa produces the fewest livestock overall, with production focused on small ruminants, including goats and sheep.

WHICH ANIMALS ARE KEPT AS LIVESTOCK?

Livestock such as horses and alpacas are often kept primarily or entirely for entertainment, labor, or fibers and not necessarily for food use. There are around 38 different species of livestock raised by humans worldwide, with over 8,800 distinct breeds. Many of these breeds have unique cultural and ecological connections to specific regions and human social groups, while some of the most commonly commercially exploited livestock worldwide, including pigs and chickens, have been selectively bred to intensify specific traits beneficial to the industrial livestock industry. Many different species of animals are kept as livestock:

• Chickens, ducks, geese, and turkeys
• Cows, goats, and sheep
• Pigs
• Camels
• Donkeys and mules
• Yak, bison, and buffalo
• Rabbits
• Llamas, alpacas, vicuñas
• Guinea pigs
• Ostrich and emu

TYPES OF LIVESTOCK FARMING

There is wide variability within livestock farming, shaped by regional practices, local ecology, and the species farmed. Livestock may be allowed to range on pastures or kept indoors in the confinement of industrial operations. Farming systems may be devoted solely to raising livestock or may grow crops concurrently. Some livestock farmers grow their own animal feed or raise animals on pasture, while many others purchase livestock feed produced elsewhere. Industrial animal farming systems, in particular, are entirely dependent on commercially manufactured animal feed to sustain high numbers of livestock in confinement.

INTENSIVE LIVESTOCK FARMING

Intensive livestock farming is an industrial production method that concentrates large numbers of animals in confined areas, often indoors in barns or pens. Animals in these industrial facilities generally do not have outdoor access and have minimal space to move around. Especially in high-income nations, the vast majority of cattle, pigs, and poultry are farmed in industrial confined animal feeding operations (CAFOs).

Industrial livestock production aims to breed and slaughter large numbers of animals as cheaply as possible, flooding commodity markets with inexpensive, mass-produced meat and dairy products. Compared to the animal densities in rangeland systems that practice extensive animal agriculture, CAFOs raise animals in extraordinarily high densities on very small areas of land. While the land footprint of CAFOs is small compared to the amount of pasture that would be required to raise the same number of animals outdoors, CAFOs rely on importing industrially farmed animal feed. Outsourcing animal nutrition to other farms makes the true land and resource footprint of CAFO products much larger than the land occupied by the CAFO facility. 

Intensive livestock farming is the dominant production model in the US, where a few large agribusiness companies control most of the livestock industry. Four large firms dominate over 85% of the US beef industry. This market concentration makes it difficult for smaller producers to compete against industrial giants and leaves independent livestock farmers vulnerable to supply chain disruptions and market fluctuations that agribusiness giants can better withstand.

Over the past few decades, the global industrialization of food production has spread the intensive livestock model worldwide, especially to many nations of the European Union,[1] Southeast Asia, and East Asia. In many countries, government policies support the formation of intensive production systems.[2] In the Global South, intensive livestock production—particularly for poultry and hogs—has gained a foothold in Brazil, China, Ethiopia, India, Kenya, Mexico, and Vietnam.

SEMI-INTENSIVE LIVESTOCK FARMING

In semi-intensive livestock farming, animals are permitted to graze, forage, or scavenge in enclosed pastures. However, pastures may be highly managed for nutrient content, and animals may also be given indoor shelter and supplemental food.[3] Animals may be confined to some degree during various steps in the semi-intensive production chain.

Keeping grazing animals like sheep in fenced areas of pasture is a form of semi-intensive farming.[4] Pastured pig operations are another example, where pigs spend significant time grazing and foraging outdoors while also having access to indoor housing and supplemental feed.[5] Poultry may also be raised in semi-intensive systems where they are given access to pasture during part or all of the day but kept confined in barns at night.[6]

In much of the Global South and in many lower-income nations, semi-intensive operations are typically small-scale, labor-intensive family farms that provide food for local foodwebs and reflect traditional land management patterns. In the US, semi-intensive livestock farms most often supply local and regional markets with niche or alternative products, including pastured eggs and heritage pig breeds.[7]

EXTENSIVE LIVESTOCK FARMING

In extensive livestock farming, animals roam and graze freely on large expanses of land. Extensive farming most often features ruminants like cows, sheep, and goats that naturally subsist on wild forage grasses. In contrast to intensive systems, extensive livestock production involves very low livestock densities and comparatively large areas of land. Unlike in semi-intensive systems, extensive livestock animals obtain all of their nutrition from forage and are not typically provided with year-round supplemental food.[8]

Extensive animal production may be low-yield or seasonal and can involve limited human and animal interaction except at particular points in the animals’ lives, such as when they are born, castrated, dehorned, shorn, or taken to slaughter.

Pastoralism is a particular form of extensive livestock farming practiced mostly in marginal rangelands, drylands, and other areas of the world where poor soil and arid or harsh weather conditions mean that typical field crops for human consumption cannot be grown. Subsistence pastoralists rely principally on livestock products for their nutrition. Pastoral livestock systems adapt to the seasonal availability of forage and water, relying on the natural movements of animals in search of food and naturally-occurring ecosystem biodiversity to sustain livestock.[9] Traditional shepherd grazing, practiced in rural areas of of India, Kenya, Hungary, and many other countries, is an example of pastoralism. Globally, there are around 180 million subsistence pastoralists worldwide who raise animals extensively in environments that would otherwise be unusable for agriculture.

In the US, hybrid intensive/extensive systems have become the dominant model of cattle ranching nationwide. Cattle graze vast tracts of private or public rangeland in freely-roaming herds without additional food or shelter. However, many calves intended for beef production are removed from the rangelands and transported to industrial feedlots, where they are then confined and provided with industrial animal feed designed to promote rapid growth before slaughter. Over 650 million acres of US private and public land are used for grazing livestock, more than any other form of land use in the nation. 

NOMADIC LIVESTOCK FARMING

Nomadic livestock farming is a highly mobile system based on the seasonal migration of both humans and animals. Nomadic communities do not have permanent settlements, and they may travel significant distances to seek out available pasture and water. This system is highly dependent on biodiversity and the seasonal growth cycles of plants. Goats, sheep, cows, and camels are common livestock raised in this system, and they live and move in social groups with kinship-based nomadic communities.

Nomadic livestock farming, also called nomadic pastoralism, is primarily practiced in arid and semi-arid areas of the world, including Kenya, Iran, India, Somalia, Algeria, Russia, Afghanistan, and Nepal. In Iran, nomadic livestock herders keep nearly 60% of all sheep and nearly 40% of all goats in the country.[10] In Afghanistan, around 80% of the land is used for livestock grazing by nomadic farmers. Nomadic pastoralism is a traditional cultural characteristic of farming in Somalia, where nomadic people and animals often cross national borders.[11]

TRANSHUMANT LIVESTOCK FARMING

Transhumant livestock farming is a form of pastoralism in which livestock move seasonally between ecological zones, often from highlands to lowlands, to take advantage of changing seasonal grazing opportunities. Transhumant farmers return to the same fixed pastures year after year during their seasonal moves.

Many European countries have transhumant pastoralists, who use as many as 74 million acres for grazing. There are significant areas of transhumant pastoralism in Spain and Portugal and in both Central and Eastern Europe. Cross-border transhumance occurs in France, Italy, Switzerland, and Spain, where national laws protect traditional livestock migration routes. In sub-Saharan Africa, transhumant pastoralism is often practiced to help livestock—and the people who rely on them—survive seasonal dry periods. Nearly half of livestock farmers in Cameroon are transhumant pastoralists.[12]

Traditional transhumant livestock systems can exist in balance with the ecosystems in which they have developed. Some species of plants and animals have adapted to the seasonal movements of herds. For example, transhumant herds in northwest Spain play an important role in maintaining griffon vulture populations.[13] The decline or interruption of traditional transhumant farming systems can weaken or break ecological linkages that support regional biodiversity.[14]

ORGANIC LIVESTOCK FARMING

Organic livestock farming avoids synthetic inputs, including agrichemical pesticides and fertilizers, genetically modified plants or animals, antibiotic drugs, and added growth hormones. Organic livestock farms must also promote natural resource conservation and biodiversity in their management practices. However, farmers may also use organically produced commercial feed crops, and the extra land required for producing these feed crops reduces the environmental sustainability of organic animal production.

Organic farming often occurs within semi-intensive systems. In the US, 2.3 million acres of grazing land were organically certified in 2016. In Europe, around 34 million acres were devoted to organic farming in 2019, including livestock production. Organic farming is practiced in 160 countries, although the high-income nations of the Global North dominate the global market for organic livestock products.[15]

IS LIVESTOCK FARMING BAD?

Livestock farming has very different impacts depending on where it occurs, what sort of production practices it involves, and the nature of the local food system in which it exists. Over 1 billion people in subsistence agricultural economies depend to some degree on livestock, many of them raised extensively through traditional farming methods for food and other necessities. Livestock production contributes significantly to the agricultural gross domestic product of South Asia and sub-Saharan Africa through a heterogeneous mix of small-scale industrial and extensive systems with a range of resource footprints and environmental impacts.

Some forms of livestock farming, including transhumant and pastoral farming, can play a role in preserving local biodiversity and promoting beneficial species interactions developed over long histories of interaction between livestock and natural environments. Traditional transhumant and nomadic livestock systems allow for food production from non-arable land, which farmers cannot otherwise cultivate for agriculture. In many areas of the Global South particularly, livestock farming has deep traditional cultural and kin-based ties, especially for Indigenous populations. Livestock farming may form an important part of human nutrition in areas where hunger is prevalent and there are currently no suitable plant-based alternatives for traditional animal-based foods.

In the high-income nations, intensive industrial livestock farming for the commercial agrifood supply chain is not required for local nutritional needs and has immense negative impacts on animal welfare, environmental sustainability, and human health. Industrial animal agriculture pollutes air and water, contributes to the climate crisis, and exacerbates global food disparities by providing cheap meat, dairy, and eggs in excess to wealthy consumers worldwide, and particularly in the Global North.[16]

MARKETING AND TRANSPORTATION

Over the past decade, 80% of growth in the global meat and dairy markets came from intensive livestock production, growth that has been strongly promoted by agribusiness corporations with consolidated control over profits in the livestock sector. The global meat industry has heavily marketed cheap meat products to consumers and successfully lobbied for pollution exemptions and other permissive laws and policies that facilitate industrial animal farming.

Marketing tactics promoting meat consumption are linked to high rates of chronic disease[17] in the Global North in the context of increasing malnutrition and hunger in vulnerable populations of the Global South. Aggressive marketing by animal producers in the high-income nations has resulted in a normalization of high meat consumption in the Global North and gradual dietary shifts toward more animal-based diets worldwide. These shifts continue to disrupt and co-opt traditional cultural relationships to food in many areas of the world.

In both regional and international supply chains, livestock raised in intensive systems face the hardships of long-distance transportation, including being deprived of food or water and being exposed to extreme weather during their journeys. In recent years, international live transport, which currently involves around two billion animals annually, has been exposed as a particularly inhumane practice that subjects animals to extreme confinement and suffering. 

ENVIRONMENTAL IMPACTS

High-density industrial livestock farming is a key contributor to global climate change. Every year 32 billion acres of forest, mostly in the Global South, are converted to allow grazing and cultivation of industrial feed crops for livestock, while one-third of all global grain production goes to support industrial livestock. Intensive grazing of rangelands has also contributed to degradation of 20% of the world’s grasslands.

Animal farming is responsible for 16.5% of all anthropogenic greenhouse gas emissions,[18] and methane accounts for about half of these emissions. Cattle contribute the highest emissions from sources including their digestion and manure, followed by pigs and chickens. In the last 15 years, methane emissions from cows have increased by 50% and emissions from pigs by 37%.[19]

Intensive livestock farming contaminates water and soil with large amounts of animal waste, damaging local ecosystems and wildlife. Air pollutants, including volatile organic compounds, ammonia, and hydrogen sulfide, contaminate the surrounding environment and threaten the health of nearby populations.[20]

ECONOMIC AND SOCIAL EFFECTS

The lucrative nature of corporate US meat production by agribusiness firms has prompted other countries, notably Brazil and China, to increasingly adopt the intensive farming model. And while the US has a huge appetite for its own domestic meat production, free trade agreements between the US and other countries also allow US agribusiness giants to flood markets of the Global South with cheap industrial meat, dairy, and industrial animal feed.

Free trade agreements also eliminate tariffs that protect local farmers. Many small farmers are unable to compete with large-scale intensive operations and cannot access the resources and technology needed to enter consumer markets dominated by multinational agribusiness corporations benefiting from friendly regulation and massive economies of scale.

Extreme weather events brought on by climate change can disrupt traditional pastoral and extensive farming communities that raise animals in relative ecological balance, leaving their foodwebs economically and socially unstable. Environmental degradation impacts plant diversity and food sources for pastoralist livestock, making it harder for herds managed by pastoralists to find sufficient forage in their traditional ranges.[21]

DISEASES

Animals in crowded industrial conditions such as CAFOs are at higher risk of infectious diseases and more likely to transmit infectious diseases to people. To control these risks without reducing livestock densities, industrial livestock producers administer routine sub-clinical doses of antibiotics for disease prevention and growth promotion. In the Global North, use in livestock accounts for 50–80% of all antibiotic use. This practice of blanket prophylactic application of powerful antibiotics promotes the development of antimicrobial resistance, which contributes to around 23,000 deaths every year in the US. Worldwide, antibiotic resistance may cause 10 million deaths annually by 2050.[22] The World Health Organization has declared growing antimicrobial resistance one of the most critical risks to global health.[23]

Many infectious diseases of high public health concern move from animals to humans, making industrial animal farms a prime breeding ground for medically important illnesses. The COVID-19 pandemic likely arose from a disease in bats, and SARS, MERS, and HIV-AIDS all originated in animals and caused millions of human deaths worldwide. In 2009, the H1N1 swine flu pandemic emerged from intensive pig farming and killed 12,000 people in the US and up to 575,000 people worldwide in its first year of circulation. Infections arising from human contact with animals in the crowded, stressful conditions of intensive farming risk the appearance of new, highly virulent diseases, and intensive farming has been flagged as a likely hotspot for the emergence of dangerous future pandemics.

CONCLUSION

Industrial livestock production uses immense resources in the form of land, crop yields, and environmental mitigation capacity. Although certain forms of traditional small-scale livestock farming support vulnerable populations worldwide with comparatively few environmental impacts and distinct cultural value, the growing global dominance of large-scale industrial livestock production carries enormous risk to human and ecological health. Intensive livestock farming of the sort practiced by the US and other high-income nations continues to have wide-ranging negative impacts on ecosystems, animals, and rural economies. Safeguarding the future of global food production requires a transition away from the most damaging forms of industrial animal agriculture as part of a broader food systems transformation prioritizing animal welfare, human wellbeing, and environmental sustainability.

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[1] David Sanchez Carpio and Stanka Becheva, “The Urgent Case to Stop Factory Farms in Europe” (Food and Water Action Europe and Friends of the Earth Europe, September 2020), https://www.foodandwatereurope.org/wp-content/uploads/2020/10/Factoryfarms_110920_web.pdf.

[2] Yukyan Lam et al., “Industrial Food Animal Production in Low- and Middle-Income Countries: A Landscape Assessment” (Johns Hopkins Center for a Livable Future, 2016), https://clf.jhsph.edu/sites/default/files/2019-01/IFAP-in-low-and-middle-income-countries-a-landscape-assessment.pdf.

[3] J. M. Moorby and M. D. Fraser, “Review: New Feeds and New Feeding Systems in Intensive and Semi-Intensive Forage-Fed Ruminant Livestock Systems,” Animal (published online July 2021), https://doi.org/10.1016/j.animal.2021.100297.

[4] EFSA Panel on Animal Health and Welfare, “Scientific Opinion on the Welfare Risks Related to the Farming of Sheep for Wool, Meat and Milk Production,” EFSA Journal 12, no. 12 (December 2014), https://doi.org/10.2903/j.efsa.2014.3933.

[5] Hyun-Suk Park, Byungrok Min, and Sang-Hyon Oh, “Research Trends in Outdoor Pig Production—A Review,” Asian-Australasian Journal of Animal Sciences 30, no. 9 (September 2017): 1207–1214, https://doi.org/10.5713/ajas.17.0330.

[6] Mini Singh et al., “Demographics and Practices of Semi-Intensive Free-Range Farming Systems in Australia with an Outdoor Stocking Density of ≤1500 Hens/Hectare,” PLOS One 12, no. 10 (October 2017), https://doi.org/10.1371/journal.pone.0187057.

[7] M. S. Honeyman et al., “The United States Pork Niche Market Phenomenon,” Journal of Animal Science 84, no. 8 (August 2006): 2269–2275, https://doi.org/10.2527/jas.2005-680.

[8] EFSA Panel on Animal Health and Welfare, “Scientific Opinion on the Welfare Risks Related to the Farming of Sheep,” https://doi.org/10.2903/j.efsa.2014.3933.

[9] Saverio Krätli and Ilse Koehler-Rollefson, “Pastoralism: Making Variability Work” (FAO 2021), https://www.fao.org/3/cb5855en/cb5855en.pdf.

[10] Hamid R. Ansari-Renani, “An Investigation of Organic Sheep and Goat Production by Nomad Pastoralists in Southern Iran,” Pastoralism 6 (2016), https://doi.org/10.1186/s13570-016-0056-y.

[11] Rustam Haydarov et al., “Evidence-Based Engagement of the Somali Pastoralists of the Horn of Africa in Polio Immunization: Overview of Tracking, Cross-Border Operations, and Communication Strategies,” Global Health Communication 2, no. 1 (2016), https://doi.org/10.1080/23762004.2016.1205890.

[12] Paolo Motta et al., “Cattle Transhumance and Agropastoral Nomadic Herding Practices in Central Cameroon,” BMC Veterinary Research 14 (2018), https://doi.org/10.1186/s12917-018-1515-z.

[13] Pedro P. Olea and Patricia Mateo-Tomás, “The Role of Traditional Farming Practices in Ecosystem Conservation: The Case of Transhumance and Vultures,” Biological Conservation 142, no. 8 (August 2009): 1844–1853, https://doi.org/10.1016/j.biocon.2009.03.024.

[14] Tenzing Ingty, “Pastoralism in the Highest Peaks: Role of the Traditional Grazing Systems in Maintaining Biodiversity and Ecosystem Function in the Alpine Himalayas,” PLOS One 16, no. 1 (January 2021), https://doi.org/10.1371/journal.pone.0245221.

[15] M. Chander et al., “Organic Livestock Production: An Emerging Opportunity with New Challenges for Producers in Tropical Countries,” Revue Scientifique et Technique 30, no. 3 (December 2011): 969–983, https://doi.org/10.20506/rst.30.3.2092.

[16] Carpio and Becheva, “The Urgent Case to Stop Factory Farms in Europe,” https://www.foodandwatereurope.org/wp-content/uploads/2020/10/Factoryfarms_110920_web.pdf.

[17] An Pan et al., “Red Meat Consumption and Mortality: Results from 2 Prospective Cohort Studies,” Archives of Internal Medicine 172, no. 7 (April 2012): 555–563, https://doi.org/doi:10.1001/archinternmed.2011.2287.

[18] Richard Twine, “Emissions from Animal Agriculture—16.5% Is the New Minimum Figure,” Sustainability 13, no. 11 (June 2021), https://doi.org/10.3390/su13116276.

[19] Keren Dopelt, Pnina Radon, and Nadav Davidovitch, “Environmental Effects of the Livestock Industry: The Relationship between Knowledge, Attitudes, and Behavior among Students in Israel,” International Journal of Environmental Research and Public Health 16, no. 8 (April 2019), https://doi.org/10.3390/ijerph16081359.

[20] Lam et al., “Industrial Food Animal Production in Low- and Middle-Income Countries,” https://clf.jhsph.edu/sites/default/files/2019-01/IFAP-in-low-and-middle-income-countries-a-landscape-assessment.pdf.

[21] Global Agenda for Sustainable Livestock, “Smallholder Livestock Systems: Innovations for Sustainability” (Global Agenda for Sustainable Livestock, September 2019), http://www.livestockdialogue.org/fileadmin/templates/res_livestock/docs/2019_Sept_Kansas/Policy_brief_ago_2019_ok_web.pdf.

[22] Zhengxin Ma, Shinyoung Lee, and K. Casey Jeong, “Mitigating Antibiotic Resistance at the Livestock-Environment Interface: A Review,” Journal of Microbiology and Biotechnology 29 (October 2019): 1683–1692 ,https://doi.org/10.4014/jmb.1909.09030.

[23] “Global Antimicrobial Resistance and Use Surveillance System (GLASS) Report: 2021” (Geneva: World Health Organization, 2021), https://www.who.int/publications-detail-redirect/9789240027336.