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Pigs: Intelligent Animals Suffering in Farms and Slaughterhouses

Pigs “have the cognitive ability to be quite sophisticated. Even more so than dogs and certainly [more so than] three-year-olds,” says Dr. Donald Broom, a Cambridge University professor and a former scientific adviser to the Council of Europe.1 Pigs can play video games, and when given the choice, they have indicated temperature preferences in their surroundings.2

These facts should not come as a surprise to anyone who has spent time around these social, playful animals. Pigs, who can live into their teens, are protective of their young and form strong bonds with other pigs. Pigs are clean animals, but they do not sweat as humans do, so they prefer cool surfaces, such as mud, to help regulate their body temperature.3

Problems With Factory Farms
Only pigs in movies spend their lives running across sprawling pastures and relaxing in the sun. On any given day in the U.S., there are more than 68 million pigs on factory farms, and 115 million are killed for food each year.4,5

Mother pigs (sows)—who account for almost 6 million of the pigs in the U.S.—spend most of their lives in individual “gestation” crates.6 These crates are about 7 feet long and 2 feet wide—too small to allow the animals even to turn around.<sup7 After giving birth to piglets, sows are moved to “farrowing” crates, which are wide enough for them to lie down and nurse their babies but not big enough for them to turn around or build nests for their young.8

Piglets are separated from their mothers when they are as young as 10 days old. Once her piglets are gone, the sow is impregnated again, and the cycle continues for three or four years before she is slaughtered.9,10 This intensive confinement produces stress- and boredom-related behavior, such as chewing on cage bars and obsessively pressing against water bottles.11,12

After they are taken from their mothers, piglets are confined to pens until they are separated to be raised for breeding or meat.13 Every year in the U.S., millions of male piglets are castrated (usually without being given any painkillers) because consumers supposedly complain of “boar taint” in meat that comes from intact animals.14 Piglets are not castrated in the U.K. or Ireland, and the European Union is phasing out the practice by 2018.15

In extremely crowded conditions, piglets are prone to stress-related behavior such as cannibalism and tail-biting, so farmers often chop off piglets’ tails and use pliers to break off the ends of their teeth—without giving them any painkillers.16 For identification purposes, farmers also cut out chunks of the young animals’ ears.17

Please visit for an inside look into a breeding facilty, where an undercover investigator witnessed the very beginning of the lives of animals who become bacon, pork chops, and sausages.

Transportation and Slaughter
Farms all over North America ship piglets (called “feeder pigs”) to Corn Belt states such as Illinois and Indiana for “growing” and “finishing.” When they are transported on trucks, piglets weighing up to 100 pounds are given no more than 2.4 square feet of space, and farmers are warned that the piglets “probably will get sick within a few days after arrival.”18 One study confirmed that vibrations like those made by a moving truck are “very aversive” to pigs. When pigs “were trained to press a switch panel to stop for 30 seconds vibration and noise in a transport simulator … the animals worked very hard to get the 30 seconds of rest.”19

Once pigs reach “market weight” (250 to 270 pounds), the industry refers to them as “hogs” and they are sent to slaughter. The animals are shipped from all over the U.S. and Canada to slaughterhouses, most of which are in the Midwest. According to industry reports, more than 1 million pigs die en route to slaughter each year.20 No laws regulate the duration of transport, frequency of rest, or provision of food and water for the animals.21,22 Pigs tend to resist getting into the trailers, which can be made from converted school buses or multideck trucks with steep ramps, so workers use electric prods to move them along. No federal laws regulate the voltage or use of electric prods on pigs, and a study showed that when electric prods were used, pigs “vocalized, lost their balance, and tr[ied] to jump out of the loading area” and their “[h]eart rate and body temperature was significantly higher … when compared to pigs loaded using a hurdle [movable chute].”23

A typical slaughterhouse kills about 1,000 hogs per hour.24 The sheer number of animals killed makes it impossible for pigs’ deaths to be humane and painless. Because of improper stunning, many hogs are alive when they reach the scalding-hot water baths, which are intended to soften their skin and remove their hair.25 The U.S. Department of Agriculture documented 14 humane-slaughter violations at one processing plant, where inspectors found hogs who “were walking and squealing after being stunned [with a stun gun] as many as four times.”26 An industry report explains that “continuous pig squealing is a sign of … rough handling and excessive use of electric prods.” The report found that the pigs at one federally inspected slaughter plant squealed 100 percent of the time “because electric prods were used to force pigs to jump on top of each other.”27

Health Problems Caused by Eating Pork
Researchers for the National Cancer Institute have found that eating meat raises men’s risk of prostate cancer, while a study from Yale University reports that meat-based diets can cause stomach cancer and esophageal cancer as well as lymphoma.28,29,30 A study of more than 90,000 women concluded that “frequent consumption of bacon, hot dogs, and sausage was … associated with an increased risk of diabetes.”31 Scientists have also found that people who regularly eat hot dogs, sausages, or other processed or cured meats suffer from a 70 percent increase in pancreatic cancer rates.32 However, those pork products are on the daily menu for 25 percent of kids between the ages of 19 months and 2 years.33 According to another study, the children of pregnant women who consume cured meats on a daily basis run a “substantial risk of [growing a] paediatric brain tumour.”34

Every year in the U.S., food poisoning sickens up to 48 million people and kills 3,000.35 Pork products are known carriers of foodborne pathogens, including E. coli, trichinella, listeria, salmonella, and pork tapeworms. One study of 256 pork samples taken from 36 different grocery stores found that up to 63 percent of the samples were contaminated with Staphylococcus aureus bacteria.36

Because crowding creates an environment conducive to the spread of disease, pigs on factory farms are fed antibiotics and sprayed with huge amounts of pesticides. The antibiotics and pesticides remain in their bodies and are passed along to people who eat them, creating serious health hazards for humans. Pigs and other factory-farmed animals are fed 20 million pounds of antibiotics each year, and scientists believe that meat-eaters’ unwitting consumption of these drugs gives rise to strains of bacteria that are resistant to treatment.37

Environmental Hazards
Senior U.N. Food and Agriculture Organization official Henning Steinfeld reported that the meat industry is “one of the most significant contributors to today’s most serious environmental problems.”38

Each factory-farmed pig produces about 9 pounds of manure per day.39 As a result, many tons of waste end up in giant pits, polluting the air and groundwater. According to the Environmental Protection Agency, agricultural runoff is the number one source of pollution in our waterways.40 In 2012, a North Carolina hog farm had to pay a $1.5 million fine for violations of the Clean Water Act after illegally dumping waste into a stream leading to the Waccamaw River.41 And in the largest federally imposed pollution fine issued to date, pork producer Smithfield Foods paid $12.6 million for polluting the Pagan River with phosphorous-contaminated wastewater from its slaughterhouse.42

Raising animals for food also requires massive amounts of resources. Two-thirds of all agricultural land in the U.S. is used to raise animals for food or to grow grain to feed them.43 Pigs and other farmed animals are the primary consumers of water in the U.S.—a single pig may require up to 5 gallons of drinking water per day.44 In the “finishing” phase alone, during which pigs grow from 100 to 240 pounds, each hog consumes more than 500 pounds of grain, corn, and soybeans. This means that across the U.S., pigs eat tens of millions of tons of feed every year.45

What You Can Do
Stop factory-farming abuses by supporting legislation that abolishes intensive-confinement systems. McDonald’s has said that by 2022, it will stop buying pork from suppliers who use gestation crates.46 Smithfield Foods plans to ban the crates by 2017.47 In the meantime, voters in Arizona, California, Florida, Michigan and Rhode Island have banned the use of gestation crates.48,49,50 In Canada, the crates will be phased out of use by 2024.51

Stop giving your money to pig farms and slaughterhouses. Going vegan means eating for life— your life and animals’ lives. Visit to order a free copy of PETA’s vegetarian/vegan starter kit.

1Cambridge Daily News, “New Slant on Chump Chops,” Cambridge Daily News, 29 Mar. 2002.
2“The Millenium List,” The Times, 9 Jan. 2000.
3John J. McGlone, Ph.D., “Managing Heat Stress in the Outdoor Pig Breeding Herd,” Texas Tech University, 1999.
4National Agricultural Statistics Service, “Quarterly Hogs and Pigs,” U.S. Department of Agriculture, 24 June 2016.
5National Agricultural Statistics Service, “Livestock Slaughter 2015 Summary,” U.S. Department of Agriculture, April 2016.
6National Agricultural Statistics Service.
7Marc Kaufman, “In Pig Farming, Growing Concern,” The Washington Post, 18 June 2001.
9A.J. Zanella and O. Duran, Pig Welfare During Loading and Transportation: A North American Perspective, I Conferência Virtual Internacional Sobre Qualidade de Carne Suína, 16 Nov. 2000.
11Zanella and Duran.
13William G. Luce, Charles V. Maxwell, and Glenn Selk, “Managing the Sow and Litter,” Oklahoma Cooperative Extension Service, July 2003.
14Joellen Perry and Mary Jacoby, These Little Pigs Get Special Care From Norwegians,” The Wall Street Journal, 6 Aug. 2007.
15Pig Progress, “EU Banning Piglet Castration by 2018,”, 16 Dec. 2010.
16Luce, Maxwell, and Selk.
17Michael Neary and Ann Yager, “Methods of Livestock Identification,” Purdue University Department of Animal Sciences, Dec. 2002.
18John C. Rea and George W. Jesse, “Managing Purchased Feeder Pigs,” Department of Animal Sciences, University of Missouri–Columbia, 1 Oct. 1993.
19Zanella and Duran.
20John Goihl, “Transport Losses of Market Hogs Studied,” Feedstuffs, 28 Jan. 2008.
21Dennis A. Shields and Kenneth H. Mathews Jr., “Interstate Livestock Movements,” U.S. Department of Agriculture, June 2003.
22Zanella and Duran.
23Zanella and Duran.
24Lance Gay, “Faulty Practices Result in Inhumane Slaughterhouses,” Scripps Howard News Service, Feb. 2001.
25Joby Warrick, “‘They Die Piece by Piece,'” The Washington Post, 10 Apr. 2001.
27Temple Grandin, “2001 Restaurant Audits of Stunning and Handling in Federally Inspected Beef and Pork Slaughter Plants,” 2002 Meat Institute Animal Handling and Stunning Conference, Colorado State University: Department of Animal Sciences, 2002.
28R. Sinha et al., “Meat and Meat-Related Compounds and Risk of Prostate Cancer in a Large Prospective Cohort Study in the United States,” American Journal of Epidemiology, 1 Nov. 2009.
29Yale University, “Animal-Based Nutrients Linked With Higher Risk of Stomach and Esophageal Cancers,” Yale News, 15 Oct. 2001.
30Daniel J. DeNoon, “Diet Linked to Non-Hodgkin’s Lymphoma: Lots of Meat, Saturated Fat, Dairy May Raise Risk,” WebMD Health News, 9 Mar. 2004.
31M.B. Schulze et al., “Processed Meat Intake and Incidence of Type 2 Diabetes in Younger and Middle-Aged Women,” Diabetologia, 24 Oct. 2003.
32China View, “Processed Meat May Cause Pancreatic Cancer,” Xinhua News, 22 Apr. 2005.
33Associated Press, “Study: Toddlers Have Bad Eating Habits,” USA Today, 26 Oct. 2003.
34J.M. Pogoda, “Maternal Cured Meat Consumption During Pregnancy and Risk of Paediatric Brain Tumour in Offspring: Potentially Harmful Levels of Intake,” Public Health Nutrition 4.2 (2001): 183-9.
35Centers for Disease Control and Prevention, “CDC Estimates of Foodborne Illness in the United States,” U.S. Department of Health and Human Services, 7 Feb. 2012.
36Ashley M. O’Brien et al., “MRSA in Conventional and Alternative Retail Pork Products,” PLoS ONE 7 (2012).
37Jeff Donn, “Contaminated Meat Spurs Concern,” Associated Press, 18 Oct. 2001.
38U.N. News Service, “Rearing Cattle Produces More Greenhouse Gases Than Driving Cars, U.N. Report Warns,” U.N. News Centre, 29 Nov. 2006.
39Associated Press, “Rains Swell Waste Lagoons at Four Hog Farms,” 1 Dec. 2006.
40Tom Harkin, “Animal Waste Pollution in America: An Emerging National Problem,” U.S. Senate Committee on Agriculture, Nutrition, and Forestry, Dec. 1997.
41Associated Press, “Hog Farm Ordered to Pay for Wetlands Preservation,” 25 July 2012.
42David Bacon, “How US Policies Fueled Mexico’s Great Migration,” The Nation, 23 Jan. 2012.
43Cynthia Nickerson et al., “Major Uses of Land in the United States, 2007,” Economic Information Bulletin Number 89, U.S. Department of Agriculture, Dec. 2011.
44Theo van Kempen, “Whole Farm Water Use,” North Carolina State University Swine Extension, July 2003.
45Dr. John Carlson, “Evaluation of Corn Processing By-Products in Swine Diets,” Western Illinois University, 3 Apr. 1996.
46P.J. Huffstutter, “McDonald’s to End Pork Gestation Crate Use by 2022,” Reuters, 1 June 2012.
47Philip Walzer, “Smithfield to End Use of Gestation Crates by 2017,” The Virginian-Pilot, 9 Dec. 2011.
48Michigan State University Extension, “Understanding Consumer Support for a Gestation Crate Ban,”, Apr. 2009.
49Brendan Howard, “Michigan Lawmakers Pass Farm-Animal Welfare Bill,” DVM Newsmagazine, 2 Oct. 2009.
50Sen. Dominic J. Ruggerio et al., “An Act Relating to Animals and Animal Husbandry—Unlawful Confinement of a Covered Animal,” State of Rhode Island, 19 June 2012.
51Rod Nickel, “Under Pressure from Restaurants, Canada Farmers To Give Sows More Space,” Reuters, 6 Mar. 2014.