2001 United Kingdom foot-and-mouth outbreak

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https://en.wikipedia.org/wiki/2001_United_Kingdom_foot-and-mouth_outbreak 

 

Notice telling people to keep off the North York Moors

The outbreak of foot-and-mouth disease in the United Kingdom in 2001 caused a crisis in British agriculture and tourism. This epizootic saw 2,000 cases of the disease in farms across most of the British countryside. Over 6 million cows and sheep were killed in an eventually successful attempt to halt the disease. Cumbria was the worst affected area of the country, with 893 cases.

With the intention of controlling the spread of the disease, public rights of way across land were closed by order. This damaged the popularity of the Lake District as a tourist destination and led to the cancellation of that year's Cheltenham Festival, as well as the British Rally Championship for the 2001 season and delaying that year's general election by a month. By the time that the disease was halted in October 2001, the crisis was estimated to have cost the United Kingdom £8bn.

Background

Britain's last outbreak had been in 1967, and had been confined to a small area of the country. The Northumberland report issued after the 1967 outbreak had identified that speed was the key to stopping a future outbreak, with the recommendation of identified animals being slaughtered on the spot on the same day as identification, and the carcasses buried in quicklime.

In 1980, foot and mouth treatment policy passed from the hands of the UK Government to the European level as a result of European Community (EC) directive, 85/511. This set out procedures, such as protection and "surveillance zones", the confirmation of diagnosis by laboratory testing and that actions had to be consulted with the EC and its Standing Veterinary Committee. An earlier directive, 80/68, on the protection of groundwater gave powers to the Environment Agency to prohibit farm burials and the use of quicklime unless the site was authorised by the Agency.

Since the 1967 outbreak, there had also been significant changes in farming methods. The closure of many local abattoirs meant that animals for slaughter were now being transported greater distances.

Start of crisis

A government notice on a quarantined Oxfordshire farm

The first case of the disease to be detected was at Cheale Meats abattoir in Little Warley, Essex on 19 February 2001, in pigs from Buckinghamshire and the Isle of Wight. Over the next four days, several more cases were announced in Essex. On 23 February, a case was confirmed in Heddon-on-the-Wall, Northumberland, from the same location as the pig in the first case; this farm was later confirmed as the source of the outbreak, with the owner, Bobby Waugh of Pallion, found guilty of having failed to inform the authorities of a notifiable disease and banned from keeping farm animals for 15 years. He was later found guilty of feeding his pigs "untreated waste".

On 24 February, a case was announced in Highampton in Devon. Later in the week, cases were found in North Wales. By the beginning of March, the disease had spread to Cornwall, southern Scotland and the Lake District where it took a particularly strong hold.

During investigation of the Great Heck rail crash, which took place on 28 February in North Yorkshire, investigators visiting the crash site had to go through a decontamination regimen, to prevent possible contamination of the crash site's soil with the virus.

The Ministry of Agriculture, Fisheries and Food (MAFF) adopted a policy of "contiguous cull" – all animals within 3 kilometres (3,000 m) of known cases would be slaughtered. This was immediately clarified as applying only to sheep, not cows or pigs. The policy of MAFF was that where affected carcasses from the cull could not be disposed on site, they would have to be taken to a rendering plant in Widnes; as such, the corpses of infected animals were taken through disease-free areas.

By 16 March, the number of cases was at 240. Around the time, the Netherlands had a small outbreak, though the disease was contained by vaccination; the vaccinated animals would later be destroyed, in line with EU requirements on trading.

Professor David King was appointed to approach MAFF policy in a scientific manner, alongside Professor Roy Anderson, an epidemiologist who had been modelling human diseases at Imperial College and was on the committee concerned with BSE. By the end of March the disease was at its height, with up to 50 new cases a day.

In April, King announced that the disease was "totally under control". The effort to prevent the spread of the disease, which caused a complete ban of the sale of British pigs, sheep and cattle until the disease was confirmed eradicated, concentrated on a cull and then by burning all animals located near an infected farm. The complete halt on movement of livestock, cull, and extensive measures to prevent humans carrying the disease on their boots and clothing from one site to another, brought the disease under control during the summer. The culling required resources that were not immediately to hand. With about 80,000–93,000 animals per week being slaughtered, MAFF officials were assisted by units from the British Army commanded by Brigadier Alex Birtwistle. From May to September, about five cases per day were reported.

End of outbreak

The final case was reported on Whygill Head Farm near Appleby in Cumbria on 30 September. The Department for Environment, Food and Rural Affairs (Defra) downgraded to "high risk" the last area to be denoted "infected" on 29 November. The last cull in the UK was performed on 1 January 2002 on 2,000 sheep at Donkley Woods Farm, Bellingham, Northumberland. Restrictions on livestock movement were retained into 2002.

The use of a vaccine to halt the spread of the disease was repeatedly considered during the outbreak, but the government never decided to use it after pressure from the National Farmers Union. Although the vaccine was believed to be effective, export rules would prevent the export of British livestock in the future, and it was decided that this was too great a price to pay, although this was controversial because the value of the export industry (£592 million per year; MAFF figures reported by the Guardian) was small compared to losses to tourism resulting from the measures taken. Following the outbreak, the law was changed to allow vaccinations rather than culling.

The consensus today is that the FMD virus came from infected or contaminated meat that was part of the swill being fed to pigs at Burnside Farm in Heddon-on-the-Wall. The swill had not been properly heat-sterilized and the virus had thus been allowed to infect the pigs.

Seeing as FMD virus was apparently not present in the UK beforehand, and given the import restrictions for meat from countries known to harbour FMD, it is likely that the infected meat had been illegally imported to the UK. Such imports are likely to be for the catering industry and a total ban on the feeding of catering waste containing meat or meat products was introduced early in the epidemic.

Spread to the rest of Europe

Number of outbreaks of foot and mouth disease in Western Europe in 2001

Several cases of foot and mouth were reported in Ireland and mainland Europe, following unknowing transportation of infected animals from the UK. The cases sparked fears of a continent-wide pandemic, but these proved unfounded.

The Netherlands was the worst affected country outside the UK, suffering 25 cases. Vaccinations were used to halt the spread of the disease. However, the Dutch went on to slaughter all vaccinated animals and in the end 250,000–270,000 cattle were destroyed, resulting in significantly more cattle slaughtered per infected premises than in the UK.

Ireland suffered one case in a flock of sheep in Jenkinstown in County Louth in March 2001. A cull of healthy livestock around the farm was ordered. Irish special forces sniped wild animals capable of bearing the disease, such as deer, in the area. The outbreak greatly affected the Irish food and tourism industry. The 2001 Saint Patrick's Day festival was cancelled, but later rescheduled two months later in May. Severe precautionary measures had been in place throughout Ireland since the outbreak of the disease in the UK, with most public events and gatherings cancelled, controls on farm access, and measures such as disinfectant mats at railway stations, public buildings and university campuses. The 2001 Oireachtas Rince na Cruinne, or Irish Dance World Championships, was cancelled this year due to these measures. Causeway 2001, an Irish Scouting Jamboree was also cancelled. Three matches involving Ireland in rugby union's 2001 Six Nations Championship were postponed until the autumn.

France suffered two cases, on 13 March and 23 March.

Belgium, Spain, Luxembourg and Germany carried out some precautionary slaughters, but all tests eventually proved negative. Further false alarms that did not result in any culling were signalled in Finland, Sweden, Denmark and Italy. All other European countries imposed livestock movement restrictions from infected or potentially infected countries.

The outbreak caused the delay by a month of the local elections. Part of the reason was that bringing together so many farmers at polling stations might cause extensive spread of the disease. However, more importantly, it was widely known before the outbreak that the Government had chosen the day of the local elections to hold the general election. Holding a general election during the height of the crisis was widely seen as impossible – Government work is much reduced during the four-week campaign and it was seen as inappropriate to divert attention away from management of the crisis. The announcement was leaked to newspapers at the end of March. Prime Minister Tony Blair confirmed the decision on 2 April. Opposition leader William Hague concurred with the reasons for delay, and even suggested a further delay to ensure that the crisis was truly over (though it was alleged that he was hoping the Tories would be more popular and do better at the coming election the later it took place, perhaps because of bad government handling of the foot and mouth situation). The general election was eventually held on 7 June, along with the local elections. It was the first delay of an election since the Second World War.

Following the election, Blair announced a re-organisation of the government departments. Largely in response to the perceived failure of the Ministry of Agriculture, Fisheries and Food to respond to the outbreak quickly and effectively enough, the ministry was merged with elements of the Department of the Environment, Transport and the Regions to form the Department for Environment, Food and Rural Affairs (Defra).

Reports

A government notice on the 2001 UK foot and mouth disease outbreak. King's Sutton is in Northamptonshire, south of Banbury.

As the 2001 outbreak seemed to cause as much harm as the previous outbreak in 1967, there was a widespread government and public perception that little had been learnt from the previous epizootic (despite the publication in 1968 of a report, the Northumberland Inquiry, on the previous outbreak). In August 2001 therefore, in an effort to prevent this failure to learn from history from happening again, HM Government launched three inquiries into various aspects of the crisis. They were:

• Inquiry into the lessons to be learned from the foot and mouth disease outbreak of 2001. This inquiry was devoted specifically to the government's handling of the crisis. It was chaired by Sir Iain Anderson CBE, previously a special adviser to Tony Blair, and reported in July 2002.
• The Royal Society Inquiry into Infectious Diseases in Livestock. This inquiry examined the scientific aspects of the crisis, for instance the efficacy of vaccinations, the way the virus spreads and so on. It was chaired by Sir Brian Follett and also reported in July 2002.
• Policy Commission on the Future of Farming and Food. This inquiry focused on the long-term production and delivery of food within the country. It was chaired by Sir Donald Curry and reported in January 2002.

All three inquiries reported their findings to the public. However, the inquiries themselves took place in private. The lack of a full public inquiry into the crisis caused a group of farmers, business leaders and media organisations to lodge an appeal at the High Court against the government's decision not to hold such an inquiry. Margaret Beckett, Secretary of State for Environment, Food and Rural Affairs, had ruled out a public inquiry on the grounds that it would be too costly and take too long. After a four-day hearing, the court sided with Beckett and the Government.

An Independent Inquiry into Foot and Mouth Disease in Scotland initiated by the Royal Society of Edinburgh was chaired by Professor Ian Cunningham. This embraced not only the scientific aspects of the outbreak, but also economic, social and psychological effects of the event. The costs to Scottish agriculture of the FMD outbreak were estimated to be £231m and the loss of gross revenue to tourism to be between £200–250m for Scotland as a whole. It recommended that there should be a regional laboratory in Scotland, and priority be given to the development of testing procedures. The delay in imposing a ban of all movements until the third day after confirmation, the use of less than transparent modelling techniques and the failure to call on more than a fraction of the considerable relevant scientific expertise available in Scotland were criticised. The case for emergency protective vaccination, without subsequent slaughter, was supported by the evidence and it was recommended that contingency plans should include emergency barrier, or ring, vaccination as an adjunct to slaughter in clinical cases. Reservations about the consumption of meat and milk from vaccinated animals were seen to be unjustified. The importance of biosecurity at all times and throughout the agricultural industry was emphasised and it stated that SEERAD (The Scottish Executive Environment and Rural Affairs Department) should take the lead in establishing standards to be applied in normal times and at the start of an outbreak. A Chief Veterinary Officer (Scotland) should be appointed and a "Territorial Veterinary Army" formed from professionals to be called upon should need arise. Burial of carcasses, where conditions permit, was identified as the preferred option for disposal of slaughtered animals. The Scottish Environment Protection Agency (SEPA) should have a clear role in contingency planning and management of any future emergency. There was a need for operational guidelines for slaughtermen. In formulating movement restriction, the dispersed nature of many holdings should be taken into account. There should be a clear and consistent strategy for compensation for slaughtered animals. The closing down of the country initially for no more than three weeks and then reopening in non-affected areas was recommended. Great importance was placed on contingency planning, on the need for regular exercises and on the setting up of an independent standing committee to monitor the maintenance of effective planning. In all, some twenty seven recommendations were made to the Scottish Executive.

The Farm Animal Welfare Council, an independent advisory body established by the Government in 1979, also published a report. Its recommendations including material from both The Royal Society Inquiry into Infectious Diseases in Livestock and the Independent Inquiry into Foot and Mouth Disease in Scotland.

Health and social consequences

The Department of Health (DH) sponsored a longitudinal research project investigating the health and social consequences of the 2001 outbreak of FMD. The research team was led by Dr Maggie Mort of Lancaster University and fieldwork took place between 2001 and 2003. Concentrating on Cumbria as the area that was worst hit by the epidemic, data has been collected via interviews, focus groups and individual diaries in order to document the consequences that the FMD outbreak had on people's lives. In 2008, a book based on this study was published, titled Animal Disease and Human Trauma, emotional geographies of disaster.

Under the EU systems, compensation could be paid to farmers, but only those whose animals were slaughtered; those who suffered as a result of movement restrictions, albeit due to government action, could not be compensated.

Later reaction

In the light of the reports' extensive recommendations, in June 2004, Defra held a simulation exercise in five areas around the country to test new procedures to be employed in the event of a future outbreak. Unlike the outbreak in the 1960s, the main reason that MAFF failed to respond quickly enough was the high level of cattle movement in the modern-day market: by the 21st century, cattle were being moved quickly up and down the country without tests for disease. However, the government was accused by the NFU of acting too slowly in the early stages of the outbreak, and the Agriculture Minister attempted at least as late as 11 March to claim incorrectly that the outbreak was under control.

Environmental impact of meat production

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Environmental_impact_of_meat_production 

The environmental impact of meat production varies because of the wide variety of agricultural practices employed around the world. All agricultural practices have been found to have a variety of effects on the environment. Some of the environmental effects that have been associated with meat production are pollution through fossil fuel usage, animal methane, effluent waste, and water and land consumption. Meat is obtained through a variety of methods, including organic farming, free range farming, intensive livestock production, subsistence agriculture, hunting, and fishing.

Nutritional value and environmental impact of animal products, compared to agriculture overall

Categories	Contribution of farmed animal product [%]
Calories	18
Proteins	37
Land use	83
Greenhouse gases	58
Water pollution	57
Air pollution	56
Freshwater withdrawals	33

Meat is considered one of the prime factors contributing to the current biodiversity loss crisis. The 2019 IPBES Global Assessment Report on Biodiversity and Ecosystem Services found that industrial agriculture and overfishing are the primary drivers of the extinction, with the meat and dairy industries having a substantial impact. The 2006 report Livestock's Long Shadow, released by the Food and Agriculture Organization (FAO) of the United Nations, states that "the livestock sector is a major stressor on many ecosystems and on the planet as a whole. Globally it is one of the largest sources of greenhouse gases (GHG) and one of the leading causal factors in the loss of biodiversity, and in developed and emerging countries it is perhaps the leading source of water pollution."

Meat production is a major driver of climate change. A 2017 study published in the journal Carbon Balance and Management found animal agriculture's global methane emissions are 11% higher than previous estimates based on data from the Intergovernmental Panel on Climate Change. Some fraction of these effects is assignable to non-meat components of the livestock sector such as the wool, egg and dairy industries, and to the livestock used for tillage. Livestock have been estimated to provide power for tillage of as much as half of the world's cropland. Multiple studies have found that increases in meat consumption associated with human population growth and rising individual incomes will increase carbon emissions and further biodiversity loss. On August 8, 2019, the IPCC released a summary of the 2019 special report which asserted that a shift towards plant-based diets would help to mitigate and adapt to climate change.

Consumption and production trends

Changes in demand for meat may change the environmental impact of meat production by influencing how much meat is produced. It has been estimated that global meat consumption may double from 2000 to 2050, mostly as a consequence of increasing world population, but also partly because of increased per capita meat consumption (with much of the per capita consumption increase occurring in the developing world). Global production and consumption of poultry meat have recently been growing at more than 5 percent annually. Meat consumption typically increases as people and countries get richer. There is a strong positive relationship between meat consumption per capita and gross domestic product (GDP) per capita. According to an article written by Dave Roos "industrialized Western nations average more than 220 pounds of meat per person per year, while the poorest African nations average less than 22 pounds per person." Trends vary among livestock sectors. For example, global per capita consumption of pork has increased recently (almost entirely due to changes in consumption within China), while global per capita consumption of ruminant meats has been declining.

Grazing and land use

The amount of globally needed agricultural land would be reduced by almost half if no beef or mutton would be eaten.

Mean land use of different foods

Food Types	Land Use (m2year per 100g protein)
Lamb and mutton	185
Beef	164
Cheese	41
Pork	11
Poultry	7.1
Eggs	5.7
Farmed fish	3.7
Groundnuts	3.5
Peas	3.4
Tofu	2.2

Dryland grazing on the Great Plains in Colorado.

In comparison with grazing, intensive livestock production requires large quantities of harvested feed, this overproduction of feed can also hold negative effects. The growing of cereals for feed in turn requires substantial areas of land.

It takes seven pounds of feed to produce a pound of beef (live weight), more than three pounds for a pound of pork, and less than two pounds for a pound of chicken. Assumptions about feed quality are implicit in such generalizations. For example, production of a pound of beef cattle live weight may require between 4 and 5 pounds of feed high in protein and metabolizable energy content, or more than 20 pounds of feed of much lower quality.

About 85 percent of the world’s soybean crop is processed into meal and vegetable oil, and virtually all of that meal is used in animal feed. Approximately six percent of soybeans are used directly as human food, mostly in Asia. In the contiguous United States, 127.4 million acres of crops are grown for animal consumption, compared to the 77.3 million acres of crops grown for human consumption.

Where grain is fed, less feed is required for meat production. This is due not only to the higher concentration of metabolizable energy in grain than in roughages, but also to the higher ratio of net energy of gain to net energy of maintenance where metabolizable energy intake is higher.

Free-range animal production requires land for grazing, which in some places has led to land use change. According to FAO, "Ranching-induced deforestation is one of the main causes of loss of some unique plant and animal species in the tropical rainforests of Central and South America as well as carbon release in the atmosphere."

Raising animals for human consumption accounts for approximately 40% of the total amount of agricultural output in industrialized countries. Grazing occupies 26% of the earth's ice-free terrestrial surface, and feed crop production uses about one third of all arable land. More than one-third of U.S. land is used for pasture, making it the largest land-use type in the contiguous United States.

Land quality decline is sometimes associated with overgrazing, as these animals are removing much needed nutrients from the soil without the land having time to recover. Rangeland health classification reflects soil and site stability, hydrologic function, and biotic integrity. By the end of 2002, the US Bureau of Land Management (BLM) had evaluated rangeland health on 7,437 grazing allotments (i.e., 35 percent of its grazing allotments or 36 percent of the land area contained in its grazing allotments) and found that 16 percent of these failed to meet rangeland health standards due to existing grazing practices or levels of grazing use. This led the BLM to infer that a similar percentage would be obtained when such evaluations were completed. Soil erosion associated with overgrazing is an important issue in many dry regions of the world. On US farmland, much less soil erosion is associated with pastureland used for livestock grazing than with land used for production of crops. Sheet and rill erosion is within estimated soil loss tolerance on 95.1 percent, and wind erosion is within estimated soil loss tolerance on 99.4 percent of US pastureland inventoried by the US Natural Resources Conservation Service.

Environmental effects of grazing can be positive or negative, depending on the quality of management, and grazing can have different effects on different soils and different plant communities. Grazing can sometimes reduce, and other times increase, biodiversity of grassland ecosystems. In beef production, cattle ranching can provide supporting and habitat services by maintaining habitats that have evolved to thrive alongside grazing. Lightly grazed grasslands also tend to thrive more with biodiversity than overgrazed or nongrazed grasslands. A study comparing virgin grasslands under some grazed and nongrazed management systems in the US indicated somewhat lower soil organic carbon but higher soil nitrogen content with grazing. In contrast, at the High Plains Grasslands Research Station in Wyoming, the top 30 cm of soil contained more organic carbon as well as more nitrogen on grazed pastures than on grasslands where livestock were excluded. Similarly, on previously eroded soil in the Piedmont region of the US, pasture establishment with well-managed grazing of livestock resulted in high rates of both carbon and nitrogen sequestration relative to results obtained where grass was grown without grazing. Such increases in carbon and nitrogen sequestration can help mitigate greenhouse gas emission effects. In some cases, ecosystem productivity may be increased due to grazing effects on nutrient cycling.

The livestock sector is also the primary driver of deforestation in the Amazon, with around 80% of all converted land being used to rear cattle. 91% of land deforested since 1970 has been converted to cattle ranching.

Research has argued that a shift to meat-free diets could provide a safe option to feed a growing population without further deforestation, and for different yields scenarios.

Water use

Estimated virtual water requirements
for various foods (m³ water/ton)

	Hoekstra & Hung (2003)	Chapagain & Hoekstra (2003)	Zimmer & Renault (2003)	Oki et al. (2003)	Average
Beef		15,977	13,500	20,700	16,730
Pork		5,906	4,600	5,900	5,470
Cheese		5,288			5,290
Poultry		2,828	4,100	4,500	3,810
Eggs		4,657	2,700	3,200	3,520
Rice	2,656		1,400	3,600	2,550
Soybeans	2,300		2,750	2,500	2,520
Wheat	1,150		1,160	2,000	1,440
Maize	450		710	1,900	1,020
Milk		865	790	560	740
Potatoes	160		105		130

Water requirement per kilocalorie

Water requirement per gram of protein

Almost one-third of the water used in the western United States goes to crops that feed cattle. This is despite the claim that withdrawn surface water and groundwater used for crop irrigation in the US exceeds that for livestock by about a ratio of 60:1. This excessive use of river water distresses ecosystems and communities, and drives scores of species of fish closer to extinction during times of drought.

Irrigation accounts for about 37 percent of US withdrawn freshwater use, and groundwater provides about 42 percent of US irrigation water. Irrigation water applied in production of livestock feed and forage has been estimated to account for about 9 percent of withdrawn freshwater use in the United States. Groundwater depletion is a concern in some areas because of sustainability issues (and in some cases, land subsidence and/or saltwater intrusion). A particularly important North American example where depletion is occurring involves the High Plains (Ogallala) Aquifer, which underlies about 174,000 square miles in parts of eight states, and supplies 30 percent of the groundwater withdrawn for irrigation in the US. Some irrigated livestock feed production is not hydrologically sustainable in the long run because of aquifer depletion. Rainfed agriculture, which cannot deplete its water source, produces much of the livestock feed in North America. Corn (maize) is of particular interest, accounting for about 91.8 percent of the grain fed to US livestock and poultry in 2010. About 14 percent of US corn-for grain land is irrigated, accounting for about 17 percent of US corn-for-grain production, and about 13 percent of US irrigation water use, but only about 40 percent of US corn grain is fed to US livestock and poultry.

Effects on aquatic ecosystems

Mean eutrophying emissions (water pollution) of different foods per 100g of protein

Food Types	Eutrophying Emissions (g PO43-eq per 100g protein)
Beef	301.4
Farmed Fish	235.1
Farmed Crustaceans	227.2
Cheese	98.4
Lamb and Mutton	97.1
Pork	76.4
Poultry	48.7
Eggs	21.8
Groundnuts	14.1
Peas	7.5
Tofu	6.2

In the Western United States, many stream and riparian habitats have been negatively affected by livestock grazing. This has resulted in increased phosphates, nitrates, decreased dissolved oxygen, increased temperature, turbidity, and eutrophication events, and reduced species diversity. Livestock management options for riparian protection include salt and mineral placement, limiting seasonal access, use of alternative water sources, provision of "hardened" stream crossings, herding, and fencing. In the Eastern United States, a 1997 study found that waste release from pork farms have also been shown to cause large-scale eutrophication of bodies of water, including the Mississippi River and Atlantic Ocean (Palmquist, et al., 1997). In North Carolina, where the study was done, measures have since been taken to reduce the risk of accidental discharges from manure lagoons; also, since then there is evidence of improved environmental management in US hog production. Implementation of manure and wastewater management planning can help assure low risk of problematic discharge into aquatic systems.

Greenhouse gas emissions

Mean greenhouse gas emissions for different food types

Food Types	Greenhouse Gas Emissions (g CO2-Ceq per g protein)
Ruminant Meat	62
Recirculating Aquaculture	30
Trawling Fishery	26
Non-recirculating Aquaculture	12
Pork	10
Poultry	10
Dairy	9.1
Non-trawling Fishery	8.6
Eggs	6.8
Starchy Roots	1.7
Wheat	1.2
Maize	1.2
Legumes	0.25

At a global scale, the FAO has recently estimated that livestock (including poultry) accounts for about 14.5 percent of anthropogenic greenhouse gas emissions estimated as 100-year CO₂ equivalents. A previous widely cited FAO report using somewhat more comprehensive analysis had estimated 18 percent. Because this emission percentage includes contributions associated with livestock used for the production of draft power, eggs, wool and dairy products, the percentage attributable to meat production alone is significantly lower, as indicated by the report's data. The indirect effects contributing to the percentage include emissions associated with the production of feed consumed by livestock and carbon dioxide emission from deforestation in Central and South America, attributed to livestock production. Using a different sectoral assignment of emissions, the IPCC (Intergovernmental Panel on Climate Change) has estimated that agriculture (including not only livestock, but also food crop, biofuel and other production) accounted for about 10 to 12 percent of global anthropogenic greenhouse gas emissions (expressed as 100-year carbon dioxide equivalents) in 2005 and in 2010.

Farmer ploughing rice paddy, in Indonesia. Animals can provide a useful source of draught power to farmers in the developing world

A PNAS model showed that even if animals were completely removed from US agriculture, US GHG emissions would be decreased by 2.6% (or 28% of agricultural GHG emissions). The authors state this is because of the need to replace animal manures by fertilizers and to replace also other animal coproducts, and because livestock now use human-inedible food and fiber processing byproducts. This study has been criticized, and cannot be used to answer any question about what impact a dietary shift in the US (which imports a large portion of its animal products) would have globally, as it also does not take into account the effects that this change would have on meat production and deforestation in other countries. One of this further study on the matter has suggested that farmers would reduce their land use of feed crops; currently representing 75% of US land use, and would reduce the use of fertilizer due to the lower land areas and crop yields needed. A transition to a more plant based diet is also projected to improve health, which can lead to reductions in healthcare GHG emissions, currently standing at 8% of US emissions.

In the US, methane emissions associated with ruminant livestock (6.6 Tg CH
4, or 164.5 Tg CO
2e in 2013) are estimated to have declined by about 17 percent from 1980 through 2012. Globally, enteric fermentation (mostly in ruminant livestock) accounts for about 27 percent of anthropogenic methane emissions, and methane accounts for about 32 to 40 percent of agriculture's greenhouse gas emissions (estimated as 100-year carbon dioxide equivalents) as tabulated by the IPCC. Methane has a global warming potential recently estimated as 35 times that of an equivalent mass of carbon dioxide. The magnitude of methane emissions were recently about 330 to 350 Tg per year from all anthropogenic sources, and methane's current effect on global warming is quite small. This is because degradation of methane nearly keeps pace with emissions, resulting in a relatively little increase in atmospheric methane content (average of 6 Tg per year from 2000 through 2009), whereas atmospheric carbon dioxide content has been increasing greatly (average of nearly 15,000 Tg per year from 2000 through 2009).

Testing Australian sheep for exhaled methane production (2001), CSIRO.

Mitigation options for reducing methane emission from ruminant enteric fermentation include genetic selection, immunization, rumen defaunation, outcompetition of methanogenic archaea with acetogens, introduction of methanotrophic bacteria into the rumen, diet modification and grazing management, among others. The principal mitigation strategies identified for reduction of agricultural nitrous oxide emission are avoiding over-application of nitrogen fertilizers and adopting suitable manure management practices. Mitigation strategies for reducing carbon dioxide emissions in the livestock sector include adopting more efficient production practices to reduce agricultural pressure for deforestation (such as in Latin America), reducing fossil fuel consumption, and increasing carbon sequestration in soils. A study conducted by Meat and Livestock Australia, CSIRO and James Cook University discovered that adding the seaweed Asparagopsis taxiformis to the cattle's diet can reduce methane by up to 99%, and reported a 3% seaweed diet resulted in an 80% reduction in methane.

In New Zealand, nearly half of [anthropogenic] greenhouse gas emission is associated with agriculture, which plays a major role in the nation's economy, and a large fraction of this is assignable to the livestock industry. Some fraction of this is assignable to meat production: FAO data indicate that meat accounted for about 7 percent of product tonnage from New Zealand's livestock (including poultry) in 2010. Livestock sources (including enteric fermentation and manure) account for about 3.1 percent of US anthropogenic greenhouse gas emissions expressed as carbon dioxide equivalents, according to US EPA figures compiled using UNFCCC methodologies. Among sheep production systems, for example, there are very large differences in both energy use and prolificacy; both factors strongly influence emissions per kg of lamb production.

According to a 2018 study in the journal Nature, a significant reduction in meat consumption will be "essential" to mitigate climate change, especially as the human population increases by a projected 2.3 billion by the middle of the century. A 2019 report in The Lancet recommended that global meat consumption be reduced by 50 percent to mitigate climate change.

On August 8, 2019, the IPCC released a summary of the 2019 special report which said that a shift towards plant-based diets would help to mitigate and adapt to climate change.

In November 2017, 15,364 scientists worldwide signed a "Warning to Humanity" calling for, among other things, drastically diminishing humanity's per capita consumption of meat.

Effect of air pollution on human respiratory health

Mean acidifying emissions (air pollution) of different foods per 100g of protein

Food Types	Acidifying Emissions (g SO2eq per 100g protein)
Beef	343.6
Cheese	165.5
Pork	142.7
Lamb and Mutton	139.0
Farmed Crustaceans	133.1
Poultry	102.4
Farmed Fish	65.9
Eggs	53.7
Groundnuts	22.6
Peas	8.5
Tofu	6.7

Meat production is one of the leading causes of greenhouse gas emissions and other particulate matter pollution in the atmosphere. This type of production chain produces copious byproducts; endotoxin, hydrogen sulfide, ammonia, and particulate matter (PM), such as dust, are all released along with the aforementioned methane and CO
2. Furthermore, elevated greenhouse gas emissions have been associated with respiratory diseases like asthma, bronchitis, and COPD, as well as increased chances of acquiring pneumonia from bacterial infections.

In addition, exposure to PM10 (particulate matter 10 micrometers in diameter) may produce diseases that impact the upper and proximal airways. Farmers aren’t the only ones at risk for exposure to these harmful byproducts. In fact, concentrated animal feeding operations (CAFOs) in proximity to residential areas adversely affect these individuals' respiratory health similarly seen in the farmers. Concentrated hog feeding operations release air pollutants from confinement buildings, manure holding pits, and land application of waste. Air pollutants from these operations have caused acute physical symptoms, such as respiratory illnesses, wheezing, increased breath rate, and irritation of the eyes and nose. That prolonged exposure to airborne animal particulate, such as swine dust, induces a large influx of inflammatory cells into the airways. Those in close proximity to CAFOs could be exposed to elevated levels of these byproducts, which may lead to poor health and respiratory outcomes.

Energy consumption

Energy efficiency of meat and dairy production

Data of a USDA study indicate that about 0.9 percent of energy use in the United States is accounted for by raising food-producing livestock and poultry. In this context, energy use includes energy from fossil, nuclear, hydroelectric, biomass, geothermal, technological solar, and wind sources. (It excludes solar energy captured by photosynthesis, used in hay drying, etc.) The estimated energy use in agricultural production includes embodied energy in purchased inputs.

An important aspect of energy use of livestock production is the energy consumption that the animals contribute. Feed Conversion Ratio is an animal's ability to convert feed into meat. The Feed Conversion Ratio (FCR) is calculated by taking the energy, protein, or mass input of the feed divided by the output of meat provided by the animal. A lower FCR corresponds with a smaller requirement of feed per meat out-put, therefore the animal contributes less GHG emissions. Chickens and pigs usually have a lower FCR compared to ruminants.

Intensification and other changes in the livestock industries influence energy use, emissions, and other environmental effects of meat production. For example, in the US beef production system, practices prevailing in 2007 are estimated to have involved 8.6 percent less fossil fuel use, 16 percent less greenhouse gas emissions, 12 percent less water use and 33 percent less land use, per unit mass of beef produced, than in 1977. These figures are based on an analysis taking into account feed production, feedlot practices, forage-based cow-calf operations, backgrounding before cattle enter a feedlot, and production of culled dairy cows.

Animal waste

Water pollution due to animal waste is a common problem in both developed and developing nations. The USA, Canada, India, Greece, Switzerland and several other countries are experiencing major environmental degradation due to water pollution via animal waste. Concerns about such problems are particularly acute in the case of CAFOs (concentrated animal feeding operations). In the US, a permit for a CAFO requires the implementation of a plan for the management of manure nutrients, contaminants, wastewater, etc., as applicable, to meet requirements under the Clean Water Act. There were about 19,000 CAFOs in the US as of 2008. In fiscal 2014, the United States Environmental Protection Agency (EPA) concluded 26 enforcement actions for various violations by CAFOs. Environmental performance of the US livestock industry can be compared with several other industries. The EPA has published 5-year and 1-year data for 32 industries on their ratios of enforcement orders to inspections, a measure of non-compliance with environmental regulations: principally, those under the Clean Water Act and Clean Air Act. For the livestock industry, inspections focused primarily on CAFOs. Of the 31 other industries, 4 (including crop production) had a better 5-year environmental record than the livestock industry, 2 had a similar record, and 25 had a worse record in this respect. For the most recent year of the five-year compilation, livestock production and dry cleaning had the best environmental records of the 32 industries, each with an enforcement order/inspection ratio of 0.01. For crop production, the ratio was 0.02. Of the 32 industries, oil and gas extraction and the livestock industry had the lowest percentages of facilities with violations.

With good management, manure has environmental benefits. Manure deposited on pastures by grazing animals themselves is applied efficiently for maintaining soil fertility. Animal manures are also commonly collected from barns and concentrated feeding areas for efficient re-use of many nutrients in crop production, sometimes after composting. For many areas with high livestock density, manure application substantially replaces the application of synthetic fertilizers on surrounding cropland. Manure was spread as a fertilizer on about 15.8 million acres of US cropland in 2006. Manure is also spread on forage-producing land that is grazed, rather than cropped. Altogether, in 2007, manure was applied on about 22.1 million acres in the United States. Substitution of animal manure for synthetic fertilizer has important implications for energy use and greenhouse gas emissions, considering that between about 43 and 88 MJ (i.e. between about 10 and 21 Mcal) of fossil fuel energy are used per kg of N in the production of synthetic nitrogenous fertilizers.

Manure can also have environmental benefits as a renewable energy source, in digester systems yielding biogas for heating and/or electricity generation. Manure biogas operations can be found in Asia, Europe, North America, and elsewhere. The US EPA estimates that as of July 2010, 157 manure digester systems for biogas energy were in operation on commercial-scale US livestock facilities. System cost is substantial, relative to US energy values, which may be a deterrent to more widespread use. Additional factors, such as odor control and carbon credits, may improve benefit to cost ratios. Manure can be mixed with other organic wastes in anaerobic digesters to take advantage of economies of scale. Digested waste is more uniform in consistency than untreated organic wastes, and can have higher proportions of nutrients that are more available to plants, which enhances the utility of digestate as a fertiliser product. This encourages circularity in meat production, which is typically difficult to achieve due to environmental and food safety concerns.

Effects on wildlife

Grazing (especially overgrazing) may detrimentally affect certain wildlife species, e.g. by altering cover and food supplies. The growing demand for meat is contributing to significant biodiversity loss as it is a significant driver of deforestation and habitat destruction; species-rich habitats, such as significant portions of the Amazon region, are being converted to agriculture for meat production. World Resource Institute (WRI) website mentions that "30 percent of global forest cover has been cleared, while another 20 percent has been degraded. Most of the rest has been fragmented, leaving only about 15 percent intact." WRI also states that around the world there is "an estimated 1.5 billion hectares (3.7 billion acres) of once-productive croplands and pasturelands—an area nearly the size of Russia—are degraded. Restoring productivity can improve food supplies, water security, and the ability to fight climate change." The 2019 IPBES Global Assessment Report on Biodiversity and Ecosystem Services also concurs that the meat industry plays a significant role in biodiversity loss. Around 25% to nearly 40% of global land surface is being used for livestock farming.

In North America, various studies have found that grazing sometimes improves habitat for elk, blacktailed prairie dogs, sage grouse, and mule deer. A survey of refuge managers on 123 National Wildlife Refuges in the US tallied 86 species of wildlife considered positively affected and 82 considered negatively affected by refuge cattle grazing or haying. The kind of grazing system employed (e.g. rest-rotation, deferred grazing, HILF grazing) is often important in achieving grazing benefits for particular wildlife species.

Effects on antibiotic resistance

A CDC infographic on the spread of antibiotic-resistant bacteria from farm animals

Antibiotic use in livestock is the use of antibiotics for any purpose in the husbandry of livestock, which includes treatment when ill (therapeutic), treatment of a group of animals when at least one is diagnosed with clinical infection (metaphylaxis), and preventative treatment (prophylaxis). Antibiotics are an important tool to treat animal as well as human disease, safeguard animal health and welfare, and support food safety. However, used irresponsibly, this may lead to antibiotic resistance which may impact human, animal and environmental health.

While levels of use vary dramatically from country to country, for example some Northern European countries use very low quantities to treat animals compared with humans, worldwide an estimated 73% of antimicrobials (mainly antibiotics) are consumed by farm animals. Furthermore, a 2015 study also estimates that global agricultural antibiotic usage will increase by 67% from 2010 to 2030, mainly from increases in use in developing BRIC countries.

Increased antibiotic use is a matter of concern as antibiotic resistance is considered to be a serious threat to human and animal welfare in the future, and growing levels of antibiotics or antibiotic-resistant bacteria in the environment could increase the numbers of drug-resistant infections in both. Bacterial diseases are a leading cause of death and a future without effective antibiotics would fundamentally change the way modern human as well as veterinary medicine is practised. However, legislation and other curbs on antibiotic use in farm animals are now being introduced across the globe. In 2017, the World Health Organization strongly suggested reducing antibiotic use in animals used in the food industry.

The use of antibiotics for growth promotion purposes was banned in the European Union from 2006, and the use of sub-therapeutic doses of medically important antibiotics in animal feed and water to promote growth and improve feed efficiency became illegal in the United States on 1 January 2017, through legislative change enacted by the Food and Drug Administration (FDA), which sought voluntary compliance from drug manufacturers to re-label their antibiotics.

Beneficial environmental effects

One environmental benefit of meat production is the conversion of materials that might otherwise be wasted or turned into compost to produce food. A 2018 study found that, "Currently, 70 % of the feedstock used in the Dutch feed industry originates from the food processing industry." Examples of grain-based waste conversion in the United States include feeding livestock the distillers grains (with solubles) remaining from ethanol production. For the marketing year 2009-2010, dried distillers grains used as livestock feed (and residual) in the US was estimated at 25.5 million metric tons. Examples of waste roughages include straw from barley and wheat crops (edible especially to large-ruminant breeding stock when on maintenance diets), and corn stover. Also, small-ruminant flocks in North America (and elsewhere) are sometimes used on fields for removal of various crop residues inedible by humans, converting them to food.

Small ruminants can control of specific invasive or noxious weeds (such as spotted knapweed, tansy ragwort, leafy spurge, yellow starthistle, tall larkspur, etc.) on rangeland. Small ruminants are also useful for vegetation management in forest plantations and for clearing brush on rights-of-way. Other ruminants, like Nublang cattle, are used in Bhutan to help control the growth of a species of bamboo, Yushania microphylla, which tends to crowd out indigenous species of plants. These represent alternatives to herbicide use.