Chickens: Their Life and Death in Farming Operations
A Meat and Dairy Industries Article from


Karen Davis, PhD, President, UPC United Poultry Concerns
October 2018

If there is one trait above all that leaps to my mind in thinking about chickens and watching them in our sanctuary yard among the trees and bushes, or sitting quietly together on the porch, it is cheerfulness. Chickens are cheerful birds, and when they are dispirited and oppressed, their entire being expresses their despondency. The fact that chickens become lethargic or “hysterical” in barren environments, instead of proving that they are stupid or impassive by nature, shows how sensitive they are to their surroundings, deprivations, and prospects. Likewise, when chickens are happy, their sense of well-being resonates unmistakably.

battery caged hens
Chickens in a battery cage, Esbenshade Farms, Mount Joy, Pennsylvania. Photo by: Zoe Weil.

From Forest to Farmyard to Factory Farm

In the eighteenth century, the New Jersey Quaker John Woolman noted the despondency of chickens on a boat going from America to England and the poignancy of their hopeful response when they came close to land. Behind them lay centuries of domestication, preceded and paralleled by an autonomous life in the tropical forests of Southeast Asia and the rugged foothills of the Himalayan Mountains. Descendants of the ancestors of domesticated chickens, known as jungle fowl, continue to occupy their forests homes, even as the forests are being eroded, in part to grow crops for chickens on factory farms.

Chickens are creatures of the earth who no longer live on the land in numbers anywhere near the countless billions of chickens locked in factory farm buildings virtually everywhere on earth. If there is such a thing as “earthrights,” the right of a creature to experience directly the earth from which it derived and on which its happiness depends, then chickens have been stripped of theirs. They have not changed, but the world in which they evolved to live has been violated for human convenience against their will.

Chickens were the first farmed animals to be permanently confined indoors in large numbers in automated systems based on genetic manipulation for food-production traits and reliance on antibiotics and drugs. In the twentieth century, the poultry industry in the United States became the model for animal agriculture throughout the world.

Broiler Industry magazine noted in July 1976, “Nearly every boatload of settlers that came to the New World in the seventeenth and eighteenth centuries brought with it at least a few chickens.” Chickens and other farm birds were raised in towns and villages as well as on farms, and many city people kept them in back lots. In 1930 the average number of chickens for the three million reporting farms in the United States was twenty-three. Before World War II, women were the primary caretakers of poultry in the United States. Early poultry extension programs aimed at appealing to farm women, but as poultry-keeping changed from a small farm project to a major business enterprise, it wasn’t long until, as one woman put it, “my” flock became “our” flock and ultimately “his” flock.

Since the 1950s, factory-farmed chickens have been divided into two distinct genetic types – “broiler” chickens for meat production and laying hens for egg production. Battery cages for laying hens – identical units of confinement arranged in rows and tiers – and massive confinement sheds for “broiler” chickens came into standard commercial use in the 1940s and 1950s.

By 1950, most cities and many villages had zoning laws restricting or banning the keeping of poultry, a pattern that facilitated the decline of breeding “fancy” fowl for exhibition in favor of breeding “utility” fowl for commercial food production. Poultry diseases proliferated with the growing concentration of the confined utility flocks that kept getting bigger. As a result, traditional poultry-keeping and poultry shows came to be viewed as potential disease routes, similar to current claims that chickens kept outdoors spread avian influenza viruses. Then, as now, under the direction of the United States Department of Agriculture and its counterparts around the world, an increasingly intricate system of voluntary “sanitation,” medication, and mass-extermination practices was established to protect the poultry industry from the problems the industry itself created.

Following World War II, the system known as vertical integration replaced earlier methods of chicken production. Under this system, a single company or producer, such as Tyson Foods, owns all production sectors, including the birds, hatcheries, feed mills, transportation services, medications, slaughter plants, further processing facilities, and delivery to buyers. The producer engages small farmers known as “growers” to supply the land, housing, and equipment, look after the chickens, and dispose of the waste: the dead chickens and manure-soaked wood shavings known as litter. In this way, a major capital investment along with the burden of land and water pollution is shifted to the growers.

prisoned chickens

The treatment of chickens in modern food production is surpassingly ugly and cruel. The mechanized environment, beak mutilations, starvation versus overfeeding procedures and methodologies for mass-murdering birds raise profound and unsettling questions about our society and our species. An argument that is used to silence opposition to the cruelty imposed on factory-farmed chickens is that only “happy” chickens lay zillions of eggs or put on a ton of breast muscle in their infancy. In fact, chickens do not gain weight and lay eggs in inimical surroundings because they are comfortable, content, or well-cared for, but because they are manipulated to do these things through genetics and management techniques that have nothing to do with happiness, except to destroy it. In addition, chickens in production agriculture are slaughtered at extremely young ages – laying hens at a year and a half old, “broiler” chicks at six-weeks old, and the parent flocks under two years old – before diseases and death have decimated the flocks as they would otherwise do, even with all the drugs.

Notwithstanding, millions of chickens die each year before going to slaughter, but because the volume of birds is so big – over 40 billion “broiler” chickens and 6 billion laying hens worldwide each year – the losses are economically negligible. Productivity is an economic measure referring to averages, not the well-being of individuals. Many more birds suffer and die on factory farms than on traditional farms relative to their numbers, but the amount of flesh and number of eggs is much greater on the industrial scale.

Chickens are not suited to the captivity imposed on them to satisfy human wants in the modern world. Michael W. Fox, a veterinary specialist in farmed-animal welfare, states that while chickens and other factory-farmed animals may sometimes appear to be adapted to the adverse conditions under which they are kept, on the basis of their functional and structural breakdowns in the form of multiple manmade diseases, “they are clearly not adapted.”

“Broiler” Chickens

Already by the 1980s, “broiler” chickens (the large, rapidly-growing and heavily muscled white chicks under 6 weeks old bred specifically for meat) weighed four pounds at eight weeks old – more than 40 times their original hatching weight. The U.S. Department of Agriculture bragged that if human beings grew that fast, “an eight-week-old baby would weigh 349 pounds.” A study published in 2008 said that the growth rate of these chickens had increased “by over 300 percent” in the past fifty years, resulting in “impaired locomotion and poor leg health.”

broiler chickens
Modern chicken house in the United States (Delaware). Photo by: David Hart.

It isn’t only their legs. Poultry scientists in the 1990s warned that chickens “now grow so rapidly that the heart and lungs are not developed well enough to support the remainder of the body, resulting in congestive heart failure.” But uncaringly, the poultry industry continues to increase the size and growth rate of these deeply troubled birds. At a meeting in 2014, a company executive raved that “average big bird weights have averaged 8.2 to 8.6 pounds, with nearly a dozen companies producing birds over 9 pounds.”

Chickens in nature weigh barely a pound in the first two months of life. The effects of the “human controlled evolution” of chickens bred for the meat industry are described in a 2013 article in International Hatchery Practice. Andrew A. Olkowski, DVM and his colleagues state in “Trends in Developmental Anomalies in Contemporary Broiler Chickens” that chickens with extra legs and wings, missing eyes and beak deformities “can be found in practically every broiler flock,” where “a variety of health problems involving muscular, digestive, cardiovascular, integumentary, skeletal, and immune systems” form a complex of debilitating diseases. Poultry personnel, they say, provide “solid evidence that anatomical anomalies have become deep-rooted in the phenotype of contemporary broiler chickens.”

An example is a breast muscle myopathy described in 2018 as a worldwide phenomenon. Called “wooden breast,” this condition manifests a biological impairment in “broiler” chickens so severe that the birds’ breasts develop a hard wood-like texture involving necrosis, fibrosis, and macrophage infiltration relating to the cardiopulmonary system’s inability to supply capillary blood to the bird’s massively growing breast muscle, which, as a result, hardens and dies.

Ulcerative and necrotic diseases in agribusiness chickens are endemic. Femoral head necrosis occurs when the top of the leg bone disintegrates as a result of bacterial infection, oppressive body weight, and oxygen deficiency in the contaminated chicken houses that exacerbate the birds’ pre-existing pulmonary pathologies. Necrotic enteritis involving the bacterial agent Clostridium perfringens shows intestines swollen with gas, oozing putrid fluid, and full of ulcers. Gangrenous dermatitis, a skin disease, affects the legs, wings, breast, vent, abdomen and intestines of the birds as a result of toxins emitted by Clostridium perfringens in conjunction with exposure to immunosuppressive viruses in the chicken sheds.

The 600-foot-long windowless metal sheds the chickens are raised in can be seen lined up and clustered together in rural areas. Inside the sheds, 30,000 or more young chickens sit in a swirl of disease microbes, carbon dioxide, methane gases, hydrogen sulfide, nitrous oxide, lung-destroying dust, ammonia fumes, and particles of feathers and skin suspended in the air. The ammonia fumes rise from the decomposing uric acid in the chickens’ accumulated droppings.

The National Chicken Council’s Animal Welfare Guidelines allow atmospheric ammonia in the sheds as high as 25 parts per million, even though 20 ppm burns the eyes, skin, and respiratory tracts of the chickens and weakens their immune systems by being absorbed into their bloodstream. Trying to ease the pain, afflicted birds rub their heads and eyelids against their wings. The skin on their stomachs and legs ulcerates in the ammoniated manure they are forced to sit in, and respiratory illnesses are chronic and ubiquitous.

The lighting in the chicken houses is kept dim so that the birds will move only to eat, drink and sit down again, in order to accelerate their weight gain. To a person standing in the doorway of one of these buildings – as I have often done on the Eastern Shore of Delaware, Maryland, and Virginia, where at any given time over half a billion chickens are confined – they resemble, as a journalist in the U.K. wrote, “a sea of stationary grey objects.”

At the slaughterhouse the chickens are torn from the transport crates and hung upside down on a movable rack. As they move toward the automated knife blades, they are dragged face down through an electrified water trough designed to slacken their neck muscles and contract their wing muscles for proper positioning of their heads for the blades and to paralyze the muscles of their feather follicles so that their feathers will come out more easily after they are dead. The word “stun” for this process is inaccurate, as the birds are rendered neither unconscious nor pain-free, but are electrically shocked while fully conscious, a fact described in the poultry science literature since the 1980s.

Millions of birds are conscious and breathing not only as their throats are cut but afterward, when they are plunged into the scald water tanks to loosen their feathers. In the scalder, according to former Tyson employee Virgil Butler, “the chickens scream, kick, and their eyeballs pop out of their heads.” The industry calls these birds “redskins” – birds who were scalded alive. In recent decades, various “stun/kill” methods of gassing the birds in mixtures comprising CO2, argon, nitrogen and oxygen have been experimented with and adopted in some slaughter plants. Decompression chambers have also been tried. Proponents claim these methods are less cruel. Compared to being tortured with electrical shocks, this is probably true.

Parent Flocks

The chickens raised to produce the mechanically-incubated eggs that become “broiler” chickens are called “broiler breeders.” Male and female chicks are kept separate for five months, at which time they are brought together in houses holding 8,000 to 10,000 birds with ten or twelve roosters for each 100 hens. Their eggs are taken away, so the parents never see their chicks. Roosters are routinely culled (killed) for infirmity and infertility, and because “if a particular male becomes unable to mate, his matching females will not accept another male until he is removed.” Little more than a year later the birds are sent to slaughter.

Left to eat unrestricted, the roosters and hens become so large and disabled that they cannot mate properly or even move without pain. To curb these effects, broiler breeder chickens are kept in low light on semi-starvation diets. Typically, a whole day’s food is withheld every other day starting when the birds are three weeks old. When the food is restored, the chickens rush pitifully to the feeders and gorge themselves. On days without food, they peck compulsively at spots on the floor and at the air and try to drink more water to compensate for their emptiness, but since more water results in wetter droppings, their water is limited leaving the chickens with nothing to do but suffer.

Parent flocks are plagued with disorders including an aberrant aggression by the roosters toward the hens attributed to the birds’ impoverished environment, food frustration, and genetic malfunction including the fact that chickens bred for meat have been bred to become sexually mature at three months old instead of the normal six months, so that halfway through their infancy, adult sex hormones are driving them without the neurobiological maturity of an adult bird. In addition, the rooster’s body, legs, and feet are too big for the hens who are themselves abnormally heavy, disproportioned, and slow moving and have thin, easily torn skin, and nowhere to go. “Spent” breeder hens we’ve adopted into our sanctuary in Virginia have arrived with large patches of raw bare skin and ragged feathers. The soft tuft of feathers that protects their ears is missing, exposing the ear hole, which does not happen in healthy young chickens living a normal life.

“Egg-Laying” Hens

The formation of eggs in birds is a complex biological activity based on the absorption of a specific combination of nutrients in the presence of light. A foraging hen knows how to select the calcium and other nutrients she needs to synchronize her laying cycles with the cycles of nature. Sunlight passes into her eye, sending a message to her brain, which in turn sends its own message to the anterior pituitary gland which produces a hormone that causes the ovarian follicle to enlarge. The ovary generates the hormones that stimulate the processes required to form an egg, the purpose of which in chickens, as with all birds, is to renew each generation via the natural mating of hens and roosters.

battery caged hens
Chickens in battery cages at Weaver Brothers Egg Farm, Versailles, Ohio. Photo by: Mercy For Animals.

In the twentieth century, the small and lively leghorn hens of Mediterranean descent were forced into metal cages stacked and lined in buildings farther than the eye can see through the haze of pollutants. An article in Egg Industry magazine explains that prior to the 1960s, flocks of 250 to 10,000 birds were kept on floors in houses where feeding, watering, and egg collection were done by hand. In the 1960s, a “great cage debate” arose among breeding companies, poultry professors, building designers, and equipment manufacturers over what types of facilities to invest in for the future. The cage system prevailed, with the result that by the 1970s, buildings were being constructed for flocks of 30,000 hens. By the 1980s such buildings were enlarged to hold 50,000 to 120,000 hens in wire cages.

In the 1980s, egg producers abandoned single-standing buildings for complexes “where you could put a million layers or more on a single site, then connect the houses by a common corridor and an egg belt, with all the egg production flowing into a single processing and packing plant.” The switch to these interconnected building complexes led to the now standard operations in which 150,000 to 400,000 hens are confined in a single building with two to five million debeaked hens imprisoned at one location.

Genetics, lighting, and chemicals have combined to produce a hen capable of laying 250 to 300 eggs a year, in contrast to the one or two clutches of about a dozen eggs per clutch laid in the spring and early summer by her wild relatives. Genetic selection for premature egg-laying cuts the cost of feeding and housing pullets for six months while creating many problems, including the formation of eggs that are often too big for the body of a five-month-old hen, causing her uterus to protrude, inviting infection and vent picking by her cell mates. Egg-laying is further manipulated by forcing the hens to sit under artificial lights designed to mimic the longest days of summer. The U.S. industry “corrects” the ovarian breakdown that results from these harsh practices by starving or semi-starving the hens for days and weeks at a time in the process known as forced molting. This is done to “rejuvenate” the hens’ reproductive systems for a few more months of egg-laying before slaughtering the survivors or gassing them to death.

Originally, each hen had 48 square inches of cage space, and undercover investigations indicate that many still do. The U.S. lobbying group United Egg Producers stated in the 1980s that an average of “48 square inches per bird or 12 square inches per pound of bird liveweight is adequate.” A hen requiring 74 inches merely to stand, with a wingspan of 30 to 32 inches, could be legally confined with five or ten other hens in a cage too small to stand up in let alone to spread her wings, preen, or turn around.

Criticism in Switzerland, Sweden, and the United Kingdom in the 1970s spread to the United States in the 1980s and 1990s. By the late 1990s, growing animal-welfare concern prompted United Egg Producers to commission a committee to develop recommendations that set housing standards by 2008 at 67 square inches of space per hen for white hens and 76 square inches for the slightly larger brown hens, to be increased to 86 square inches in 2017.

Similar standards were set in Canada and the European Union. In 2008 the European Commission reaffirmed a 1999 directive banning the barren cage system by 2012. Unfortunately, the ban allows so-called enriched cages. An “enriched” cage has a tiny perch, a nest box made of plastic or something else, and maybe a sprinkle of sand or wood shavings. If anything, the enriched cage system, which has also been adopted to an extent in the United States, makes the already negligible “henitentiary” inspections even more daunting – a situation Clare Druce describes in her devastating book about the poultry and egg industry, Chickens’ Lib: The Story of a Campaign. It was Clare and her mother, Violet Spalding, who launched the crusade on behalf of battery-caged hens in the early 1970s, exposing the cruelties of the British and European governments, including the Church of England and a business run by nuns, who claimed that their thousands of debeaked hens “sit in their cages all day long and sing.”

In 2008, a ballot measure in California won the support of 63 percent of voters believing the measure would ban cages in the state by 2015. However, the law did not actually require California egg producers to eliminate cages for the state’s 20 million hens, but was crafted instead to make cage systems more difficult to maintain. Welfare promoters assumed that under the new law, producers would switch to “cage-free” housing, in which thousands of hens are enclosed in single-floor units or in multi-tiered buildings with platforms designed to crowd more hens into the volume of space, enabling producers to make more money from the facility.

As a result of the law’s ambiguity, California egg producers have continued keeping the majority of hens in battery cages both barren and “enriched.” Consequently, a new voter initiative is set for the November 2018 state ballot stipulating that after certain dates, cage-free hens must have a square foot of living space per hen, or a foot and a half depending on whether the facility is single-floored or multi-tiered. Compared to living in a tiny metal cage, a hen in a cage-free facility must surely suffer less, but “cage-free” does not mean cruelty-free for birds who yearn to be outdoors all day digging in the soil, sunbathing, dustbathing, perching in trees, running around and socializing as they please. Having run a sanctuary for rescued chickens since the 1980s, I’ve watched their natural interests and behaviors revive and flourish under the influence of fresh air, sunshine and the earth under their feet.

In my visits to several “cage-free” operations in Pennsylvania and Virginia, I’ve witnessed the sadness and madness of these places, including the deafening voices of thousands of distressed hens and the hopeless dreariness of their lives. The owner of The Happy Hen in Pennsylvania joked about the ragged condition of the hens’ feathers: “We have a saying: The rougher they look, the better they lay.” The owner of Black Eagle farm in Virginia smirked when we mentioned the industry practice of killing “spent” hens by shoving them into metal boxes and hosing them to death with carbon dioxide (CO2): “I think it freezes their lungs.” This is true. The carbon dioxide burns, freezes, and asphyxiates the hens, who mean nothing to their owners.

Since roosters don’t lay eggs, more than 6 billion male chicks are trashed by the global egg industry each year as soon as they hatch in the mechanical incubators. Upon breaking out of their shells, instead of being sheltered by a mother hen’s wings, the newborns are ground up alive, electrocuted, or thrown into plastic-lined trash cans where they slowly suffocate, peeping to death as a human foot stomps them down to make room for more chicks.

Chickens Anthropomorphized

Agribusiness practitioners dismiss farmed animal advocates as “anthropomorphic.” By this they mean that the advocates have a sentimental vision of farmed animals in contrast to the utilitarian function they serve. In reality, most advocates I’ve known for more than thirty years want farmed animals to live according to their nature, instead of being configured to mirror the human desire to farm and consume them.

While sentimental anthropomorphism can be a risk, anthropomorphism based on empathy and careful observation is a valid approach to understanding other species, including chickens. Inferences about their emotions, interests, and desires rooted in our common evolutionary heritage are different from imposing alien patterns on them for purely utilitarian purposes. The treatment of chickens bred for human consumption exemplifies utilitarian anthropomorphism at its worst. Chickens are severed from all human sympathy and connectedness with the natural world while simultaneously being subjected to a set of verbal, bodily, and housing constructions designed to reflect only what the exploiters want to extract from them.

To the poultry industry, chickens are divisions of labor either piling on flesh or churning out eggs. Rhetorically, they are characterized as “broilers,” “fryers,” “layers,” “roasters,” and other dissociative marketing labels. Industry officials cultivate the idea that they care about “animal welfare,” but do so in a way that ensures public ignorance and complacency. While accusing animal advocates of anthropomorphism for saying that sick chickens mired in filth are miserable, they will turn around and tell you the chickens are “happy” and call their brand of anthropomorphism “science.”

Over the years, arguments for surgically or genetically altering chickens in the name of “better welfare” have been made. Everything from beak mutilation to breeding featherless chickens to clamping big red plastic lenses in their eyes to starving them and de-braining them and de-winging them and blinding them has been proposed and carried out in poultry research laboratories and commercial settings on the grounds of “improving welfare” for birds who are stripped of every right to fare well.

The Future

Some people believe we are moving in the direction of “humane meat” and “animal-friendly” agriculture as the public becomes better informed about the realities of factory farming. However, a decline in animal factories cannot happen as long as billions of people consume animal products. Moreover, undercover investigations of “humane” poultry farms have exposed the same misery, filth, neglect, and diseases as in the more massive operations. At the very time experts are calling animal agriculture “one of the top two or three most significant contributors to the most serious environmental problems, at every scale from local to global,” analysts are predicting the doubling of the global farmed animal population as the planet continues to overpopulate with human beings.

The good news is that animal-free eating gets easier all the time as more and more people seek healthy, delicious vegan food products and restaurant dishes. As a result of today’s culinary technology and entrepreneurial investment, people are increasingly enjoying animal-free textures and flavors without worrying about the health issues linked to animal consumption and the fact that poultry is the number one cause of foodborne illnesses in the world.

Whenever I tell people stories about our sanctuary chickens, many become very sad. The pictures I’m showing them are so different from the ones they’re used to seeing of chickens in a state of absolute, human-created misery. Many people are surprised to learn that chickens have personalities and will. My experience with chickens for more than thirty years has shown me that chickens are conscious and emotional beings with adaptable sociability and a range of interests, intentions, temperaments, and affections.

chickens in trees
From rotting in cages to roosting in branches, former battery hens enjoy life at United Poultry Concerns. UPC Sanctuary Photo by: Susan Rayfield.

If there is one trait above all that leaps to my mind in thinking about chickens and watching them in our sanctuary yard among the trees and bushes, or sitting quietly together on the porch, it is cheerfulness. Chickens are cheerful birds, and when they are dispirited and oppressed, their entire being expresses their despondency. The fact that chickens become lethargic or “hysterical” in barren environments, instead of proving that they are stupid or impassive by nature, shows how sensitive they are to their surroundings, deprivations, and prospects. Likewise, when chickens are happy, their sense of well-being resonates unmistakably.

Karen Davis, Ph.D., is the President and Founder of United Poultry Concerns, a nonprofit organization that promotes the compassionate and respectful treatment of domestic fowl, including by providing a sanctuary for chickens in Virginia. Inducted into the National Animal Rights Hall of Fame for Outstanding Contributions to Animal Liberation, she is the author of Prisoned Chickens, Poisoned Eggs: An Inside Look at the Modern Poultry Industry and other groundbreaking books and articles about the plight and delight of domestic fowl.

This article was originally published on Encyclopaedia Britannica’s Advocacy For Animals.

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