Farm Animal Welfare: Pigs

Did you know?

Life of a Pig on a Factory Farm

Approximately 100 million pigs are raised and slaughtered in the U.S. every year. As babies, they are subjected to painful mutilations without anesthesia or pain relievers: Notches are taken out of the piglets’ ears for identification, and their tails are cut off to minimize tail biting, a behavior that occurs when pigs are kept in deprived factory farm environments.

By two to three weeks of age, 15% of the piglets will have died. Those who survive are taken away from their mothers and crowded into metal-barred and concrete-floored pens in giant warehouses. Pigs live in these pens until they reach a slaughter weight of 250 pounds, usually at 6 months of age.

In the U.S. Pork Industry, more than 6 million pigs are used each year for breeding. Breeding sows are treated like piglet-making machines, living a continuous cycle of impregnation and birth, each sow being forced to produce more than 20 piglets a year. During their pregnancies, sows are kept in two-foot wide gestation crates, intended to allow pigs only enough movement necessary to stand up and lie down. Click here to learn more about the future of gestation crates.

At the end of their four-month pregnancies, the sows are moved into farrowing crates, where they spend about a month until their piglets are weaned. After the sows nurse their young for two to three weeks, the piglets are taken away to be fattened, and the sows are re-impregnated and returned to the gestation crates. This cycle continues for the pig’s entire life, about 3 to five years.

On the Farm

The type of housing system used throughout the U.S. to encourage this continuous grueling cycle of breeding sows is gestation crate to farrowing crate to gestation crate. It was developed to allow for economically efficient pork production, requiring less labor and feed than other housing arrangements.

Researchers have found outdoor, crate-free systems and loose housing systems are better for sow health and longevity. In typical U.S. factory farms, however, 100 or more sows per warehouse are kept in gestation crates placed side by side in rows of often more than 20 sows.

Alternative housing exists. An Iowa State University study found significantly lower culling and mortality rates for sows in hoop barns compared to confined sows. Commercial operations also have recorded better reproductive performance and lower mortality rates for sows in pens rather than crates. Currently used alternatives to gestation-crate housing systems include “turn-around” stalls, free-range systems, and indoor group housing.

This overcrowding and confinement is unnatural since pigs are actually very clean animals. If they are given sufficient space, pigs are careful not to soil the areas where they sleep or eat. But in factory farms, they are forced to live in unsanitary conditions – in their own feces, urine, vomit and the corpses of other pigs.

Physical/Behavioral Effects

Scientific evidence suggests that intensive confinement causes physical disorders in sows. Unnatural flooring and lack of exercise leads to obesity and crippling leg disorders. Further, the air in pig factories is laden with dust, dander, and noxious gases, which are produced as the pigs urine and feces builds up inside the warehouses, causing respiratory difficulties and the spreading of infectious diseases amongst the pigs.

Psychological Effects

Scientific evidence also suggests that intensive confinement causes psychological disorders in sows. The lack of environmental stimulation in the stall environment and the sows’ inability to perform normal behaviors including rooting, foraging, nest-building, grazing, wallowing, or practicing social behaviors, leads to psychological disorders including chronic stress, depression, aggression, and abnormal and neurotic coping behaviors, such as bar biting and sham chewing (chewing nothing).

In the Slaughterhouse

In addition to overcrowded housing, pigs also endure extreme crowding during transportation, resulting in rampant suffering and deaths, even before they arrive at the slaughterhouse. At the slaughterhouse, at the first station, pigs are supposed to be ‘stunned’ and rendered unconscious, in accordance with the federal Humane Slaughter Act. The stunning is done prior to being hung upside down by their back legs and having their throats sliced open with a knife so that they may bleed out. However, stunning at slaughterhouses is terribly imprecise, and as such, often conscious pigs are left to hang upside down, kicking and struggling, while a slaughterhouse worker attempts to slice their throats. If the worker is unsuccessful at this first station, the pigs will be carried to the next station on the slaughterhouse assembly line, the scalding tank, and boiled alive fully conscious.

What can you do?


Free range pigs are one great example of refinement. Refining your diet by choosing crate-free pork products helps ensure pigs live a better life. Click here for information on where to find pork from farms that have higher standards of care for pigs.


Grocery stores now have a large assortment of substitute pork products to replace those traditionally obtained from animals who are intensively confined. These alternatives include fake sandwich meat like bologna! You can find many of these alternatives in your local grocery store.


If we reduce the consumption of pork products by just one meal a week, approximately one billion pigs would be spared the suffering that occurs with intensive confinement operations.