Panel 3 - Maltreatment derived pathologies

Food-borne diseases associated with production methods have become increasingly common in recent years: we define them as "abuse-derived pathologies" because they are all the consequence of productivity-driven practices that ignore animal welfare.

They can be categorized into different types:

According to the FAO, the cause of these food safety problems is the increased commercialization and intensification of livestock production. Crowded, unsanitary conditions and poor waste treatment in factory farms causes animal diseases and food-borne infections and their rapid spread. [Nierenberg2003]

Food poisoning

While a small number of food poisoning incidents are caused by plant foods (pathogens spread in salads kept above refrigerator temperature and poisonous fungi), the vast majority are caused by animal products.

There are two main sources of pathogens that cause foodborne illness: 1) fecal contamination of animal products during slaughter or processing and 2) foods that have been secondarily contaminated by animal products. [PCRM2003]

The concentration of livestock into factory feedlots, broiler sheds and huge pig units causes infections and promotes their spreading. The WHO estimates that about 130 million people in Europe are affected by food-borne diseases each year. They state that "The greatest risk appears to be the production of animal foods. It is from this source that the most serious health threats originate, for instance, Salmonella, Campylobacter, E.coli and Yersinia". [Pretty2002]

Factory farm animals often arrive at slaughterhouses covered with feces, thus increasing the chance of contamination during slaughtering and processing.

The way work is organized in most slaughterhouses for poultry, for example, sistematically disperses pathogens from bird to bird. This is especially true of the chilling tanks, communal rinses for chicken carcasses that are filled with water that routinely becomes a septic brew known in the industry as "fecal soup." [Behar1994]

The most reliable estimates of human illness and of incurred costs due to food-borne pathogens come from the United States of America, where, each year, 7 foodborne pathogens (Campylobacter jejuni, Clostridium perfringens, Escherichia coli O157:H7. Listeria monocytogenes, Salmonella, Staphylococcus aureus, and Toxoplasma gondii), found in animal products, cause an estimated 3.3-12.3 million cases of foodborne illness and up to 3900 deaths. The estimated cost is $6.5-$34.9 billion (1995 US$) annually. [Buzby1997]

Animal diseases and epidemics

New diseases are emerging in the livestock industry all the time, many of them posing either an actual or a potential threat to human health. Swine fever outbreaks both in Asia and Europe, avian flu in Asia, Europe and all over the world, as well as the BSE and Foot and mouth disease epidemics, have been widely publicised and raised fears in consumers. In all cases, a huge number of animals have been - in most cases inhumanely - slaughtered. Other dangerous recent epidemics include an outbreak of Nipah disease in Malaysia. The virus killed over 100 pig farm workers and a further 150 developed non-fatal encephalitis. One million animals were slaughtered to control the newly-emerged Nipah strain. [PDIC2002]

Livestock markets are a perfect environment for the spread of epidemics. Animals who are often already stressed and exhausted by long journeys are regularly confronted with inhospitable conditions and heartless treatment. This lowers their already fragile resistance to infection.

Poultry farms are specially disease-prone. Recent epidemics of avian flu in Hong Kong, east Asia, Europe and USA have led to mass slaughter of livestock. It has been reported that, of the 23,000 birds which are sold daily in the live markets of the north-eastern US, 40 per cent are positive for specific avian influenza viruses at any given time. [OKeefe2002]

Antibiotic resistance

Since the 1960s, farm-animal health in factory farming has depended not on humane practices geared at preserving the animals'health but on the massive use of antibiotics. Many of the same drugs used to treat human illnesses are also used in livestock production, thus reducing the number of effective drugs available to fight human illnesses. Because antibiotics are given to livestock to prevent disease from spreading in crowded conditions and to increase growth, antibiotic resistance has become a global threat. [Nierenberg2003]

Thousands of animals are crammed into the unhygienic, crowded factory farms, and antibiotics are dispensed constantly through the animals' feed. Twenty-five million pounds of antibiotics are fed to American livestock annually. This is about 70% of the total amount of antibiotics produced in the U.S. each year and eight times more than the amount used in human medicine. [Union2001]

A UK House of Lords select committee enquiry stated "There is a continuing threat to human health from the imprudent use of antibiotics in animals. [...] We may face the dire prospect of revisiting the pre-antibiotic era". [House1998]

Health risks from waste disposal

In the USA only, factory farms generate an estimated 575 billion pounds of animal manure yearly. [USDA2001] The constituents and byproducts of this manure include heavy metals, antibiotics, pathogen bacteria, nitrogen and phosphorus, as well as dust, mold, bacterial endotoxins and volatile gases, all of which pose threats to human health. Since it is prohibitively expensive to transport manure for any distance [Sharpley1998], o it is typically stored and later spread or sprayed untreated on nearby cropland, posing additional risks to public health.

When contaminants from animal waste seep into underground sources of drinking water, the amount of nitrate in the ground water supply can reach dangerous levels. [EPA2005]

The microorganisms found in animal wastes, such as cryptosporidium, can pose significant threats to public health. For example, after a severe rainstorm in 1993, an outbreak of cryptosporidium in the drinking water supply in Milwaukee caused 100 deaths and made 430,000 people ill. If the presence of these microorganisms comes to exceed the threshold levels, people will not only face health risks, but will also have to find new sources for their drinking water supplies. [EPA2005]


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Buzby JC, Roberts T., Economic costs and trade impacts of microbial foodborne illness, World Health Stat Q. 1997;50(1-2):57-66.

US Environmental Protection Agency, "Region 9: Animal Waste Management - What's the problem", July 2005 - (as accessed 30-8-2005)

House of Lords Select Committee on Science and Technology, Seventh Report: Resistance to antibiotics and other microbiological agents, HMSO,

Nierenberg D., Factory Farming in the Developing World, World Watch May/June 2003

O'Keefe T., Lessons from the Flu, Poultry USA, September 2992

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PDIC Newsletter. Pig Disease Information Centre UK, Novembre 20th 2002

Pretty J., Agri-Culture - Reconnecting People, Land an Nature, Earthscan Publications, London, 2002

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