Do concentrated animal feeding operations (CAFOs), or “factory farms,” negatively impact the health and welfare of livestock?

Inside a hog CAFO.  [Untitled image of pig CAFO] Retrieved from

Inside a hog CAFO. [Untitled image of pig CAFO] Retrieved from

Jack Tallboy (B.S. Pre-Veterinary Science), Rachel Spurgeon (NRC, Environmental Conservation), Miranda Cashman (B.S. Geology)

What do 7 billion people share in common? A group that size, with all the diversity of races, religions, cultures, and languages, still unites over a meal. Access to food is a central issue and growing problem in our world.  The harder question is, how do we produce the food needed for the world’s booming population without compromising the traditional family farm and healthful agricultural practices?  Growing and raising enough food while still holding to good animal health and welfare practices becomes increasingly difficult as the global population increases.

It is probable that in the foreseeable future the world will rely on concentrated animal feeding operations (CAFOs) to feed our growing population.  Concentrated animal feeding operations are legally defined as industrial farming facilities that confine animals for 45 days or more within a year for their meat or products, such as meat, eggs or milk (Humane Society, n.d.).  CAFOs are legally considered large if they house a certain number of animals (Humane Society, n.d.).  Swine CAFOs, for example, are considered large if they contain 2500 pigs weighing 55 lbs. or more, or 10,000 pigs weighing less than 55 lbs. (Humane Society, n.d.).  Terms that can be used fairly synonymously with CAFO and factory farm are “intensively raised” and “conventionally housed.”  Intensively raised animals refers to the “intensification” of animal production, where animals are housed in more confined spaces to maximize output  (Fraser, 2005).  Conventionally housed further describes the conditions of an intensive farm, specifically referring to the minimum housing requirements needed to raise pigs on a large scale, such as concrete flooring and high packing densities (Compassion in World Farming, n.d.).  Conversely, extensive farms provide animals with free range for some part of their life, letting them find their own food and water (Penrith, n.d).

CAFOs and factory farms, especially when compared to extensive farms, are dangerously unjust to the animals they house.  Global per capita meat consumption, however, is expected to rise in the near future, especially with the increase in meat consumption in developing and emerging economies (Nigatu & Seeley, 2015).  As of 2015, the USDA reported an increase in per capita meat consumption from 10 to 18 kg in Southeast Asia, and an increase from 55 to 85 kg in South America, with a smaller increase from 86 to 92 kg in developed countries (Nigatu & Seeley, 2015).  These increases in meat consumption require an increase in meat production (Nigatu & Seeley), which suggests that CAFOs may be the most realistic option for supplying this increased demand for meat products.  CAFOs offer economically cheaper and more consumer-accessible meat than smaller independent farms because of their increased size and efficiency (Hribar, 2010).

If CAFOs are the part of the solution to the rise in global demand for meat products, our global population must acknowledge that animals housed in CAFOs are treated poorly.  In particular, the living conditions in swine CAFOs are detrimental to the health and welfare of pigs (Prunier, Heinonen & Quesnel, 2010).  Despite the poor management of CAFOs degrading the health and welfare of the animals they house, factory farming has continued to thrive largely because of mass production and economic support.  CAFOs mass-produce large quantities of meat, making it cheaper than meat produced by small or independent farms (Humane Society, n.d.).  Consumers economically support CAFOs by buying their products, thereby permitting and accepting the poor treatment of animals housed on these farms and helping CAFOs stay in business.  Also, CAFOs themselves do not enforce good management practices.  CAFOs are not restricted by animal cruelty regulations because many states exempt livestock farming from customary animal cruelty statutes (Humane Society, n.d.).  These factors allow CAFOs to continue employing poor management practices that negatively impact the animals they produce for consumption.  Looking specifically at swine CAFOs, the scientific literature supports the claim that negative impacts of CAFO conditions are detrimental to pigs physiologically, immunologically and behaviorally.

Many scientific studies support the claim that pigs housed in CAFOs suffer negative physiological consequences due to detrimental farm conditions.  Temple, Courboulay, Manteca, Velarde & Dalmau (2012) highlight the impact of joint problems in pigs raised intensively stating that such pigs are 42.1 times more likely to develop bursitis and other joint ailments than pigs raised on extensive farms.  Bursitis occurs when bursae, fluid-filled sacs that pad the joints, become inflamed, causing intense pain (Bursitis, n.d.).  Animals housed on hard, fully slatted or concrete floors are more likely to suffer from bursitis than pigs housed on smooth or bedded floors (Temple et al., 2012).  Prunier, Heinonen & Quesnel (2010), further assert that pigs raised intensively suffer from increased osteochondorsis (OCD).  Osteochondrosis includes a range of skeletal problems (Atanda, Shah & O’Brien, 2011).  Unlike bursitis, OCD is widespread because of the rapid growth and weight gain pigs are forced to endure before slaughter (Prunier et al., 2011).  Severe cases of OCD can cause pigs to lose the ability to walk, leading to premature slaughter.  Both lameness and the resulting premature slaughter are considered major indicators to poor animal welfare (Gresham, 2003, and Dewey, 2006, cited by van Grevenhof et al., 2011).  Prunier et al. (2010) further support prevalence of OCD in pigs raised for slaughter, claiming that stress caused by OCD affects 7 to 10 percent of all sows.  During the finishing period every 100 g increase in daily grain increases the risk of OCD by 20% (Busch et al., 2001 cited by Prunier et al., 2011).

Further physiological consequences to pigs caused by factory farms include increased stress that inflicts negative impacts on the pigs, the meat, and the reproductive success of sows.  Sutherland, McGlone, Davis and Bryer (2010) measured physiological changes in weaning piglets post-transport in three different space allowances.  Similarly, CAFOs house pigs in high packing densities and wean piglets early. Also, stressors post-transport can have damaging effects that are further amplified by CAFO conditions.  Sutherland et al. (2010) found that post-transport weaning piglets had lost weight, increased organ and tissue damage, increased cortisol levels, and had higher levels of various waste products in their blood (Sutherland et al., 2010).   Increased cortisol indicates the piglets were under physical and psychological stress (Merriam-Webster, n.d.).  Pigs experiencing high levels of stress during slaughter can produce less tender and less healthy meat because of an increase in pH, artificial hormones, and cortisol (Freund, 2011).  Waste products in the blood, also an indicator of increased stress, can induce a catabolic state in the pigs where the body starts to break down muscle (Sutherland et al., 2010).  Sutherland et al. (2010) attribute the increase of 3 stillborn piglets per litter over the last 20 years to rising stress levels of intensively raised pigs.  Such physiological responses to stress are due to the tight packing of animals when housed and transported (Sutherland et al., 2010).

            The literature also fully supports that there are profound immunological impacts on pigs housed in CAFOs.  They found that white blood cell levels were higher in pigs before and after transport to slaughter from the operation. Sutherland et al. (2010) proved that elevated white blood cell levels, also called leukocytosis, was known to occur in pigs experiencing acute stress (as cited in Zorrilla et al., 2001), and could lead to more serious problems with the immune system. Pakpour, Jabaji and Chénier(2012) also support this idea by stating that swine are more susceptible to antibiotic resistant bacterial infection when placed into situations of high stress. This agreement between these authors arguing that higher stress placed on pigs drastically affects their immune system  helps to show concretely that stress placed on pigs in CAFOs leads to immunological defects.

Osadebe, Hanson, Smith and Heimer (2013) show through their research of the bacteria Staphylococcus Aureus on a farm in Connecticut that antibiotic resistant strains of bacteria are increasing in number mainly due to the overuse of certain antibiotics both for normal treatment and for growth supplementation (Osadebe,et al.,2013). Overuse of antibiotics is defined as using antibiotics to treat a disease when the use of antibiotics is not absolutely necessary, or when they are used as a supplemental growth stimulant to increase production gains. It also involves the overuse of a single type of antibiotic instead of using a wide variety of treatments. This increase in antibiotic resistant bacteria was shown to increase infection rates of both swine and their human handlers with Staphylococcus bacteria related diseases by 20.6% (Osadebe, et al.,2013). The other major reason for this increase in bacteria is poor biosecurity protocols. Because antibiotic resistant bacteria are already difficult to battle, poor biosecurity can help exacerbate the problem. Some of these protocols include lack of disinfectant foot baths to remove pathogens from boots and other footwear worn in the facility, and the use of coveralls that are not washed frequently enough to ensure the prevention of pathogen transfer from swine to humans and vise versa.

Pakpour et al. (2012) also suggest that immunological defects present in sows goes on to effect their future offspring. 100% of sows tested in their experiment that had antibiotic resistant genes successfully passed them to their offspring (Pakpour et al., 2012). Because this research was performed almost 3 years after the farm on which they were performing their research stopped using antibiotics, it is very clear to see how huge a role genetics play in the battle against antibiotic resistant bacteria. This would imply that unless conditions on CAFOs improve soon, there would be several generations of pigs to come that will continue to have these degenerative immunological defects.

CAFO management practices negatively impact swine behavioral health. This is most readily seen in tail biting. Moinard, Mendl, Nicol and Green (2003) define tail biting as the gentle manipulation of one pig’s tail by another. It is the repetition of this behavior that in due course leads to bleeding and skin damage. The bleeding tail can attract other pigs and lead to more biting and can even cause serious damage to the spine. The open wound can cause infections and other possible illnesses that may result in the death of the affected pigs (Moinard, et al., 2003). Tail biting is a detrimental behavioral problem associated with CAFOs because the behavior is rarely reported “under extensive, semi-natural or feral conditions” (Van Putten, cited in, Moinard, et al., 2003). Moinard, et al.(2003) argue that abnormal behaviors such as tail biting can emerge when natural behavior is constrained. CAFOs are cited by scientists as environments that constrain natural swine behavior.

CAFOs lack stimulating environments for pigs. Researchers argue that pigs want to explore and forage, but indoor confined spaces and generally barren surroundings provide insufficient environmental enrichment opportunities (Van Putten and Dammers, Wood-Gush and Vestergaard, Petersen, cited in, Moinard, et al., 2003). Moinard, et al. (2003) support this theory with their multiple factor study on tail biting, citing straw and its environmental enrichment properties as one of the most important ways to decrease tail biting.Their study corroborated previous studies showing that pigs are significantly more involved in abnormal or damaging social behavior when they are raised in a barren environment from birth to slaughter(De Jong et al.,1998, Beattie et al., 2000,cited in,Moinard, et al.,2003). Moinard, et al. (2003) found that pigs housed on fully or partially slatted floors (allowing no straw to stay in the pen) led to an increase in tail biting by 3.2%. The scientific literature asserts that environmental stimuli early on in the pig’s life can have long reaching effects on later behavioral wellness and social interactions (Moinard, et al.,,2003). Management practices on CAFOs do not generally foster or focus on the behavioral well-being of pigs but instead focus on efficiency of the system (Moinard, et al., 2003).

In order to feed the world’s growing population and increase animal welfare standards within CAFOs, stricter regulations directed towards good management practices and healthier animals should be enacted upon them.

To ameliorate the substandard conditions imposed on swine in CAFOs, yet still feed the growing world population takes a better solution than simply eliminating CAFOs all together. Taking a page out of what previously was a much maligned industry that has since changed its image and many of its management practices, slaughterhouses have come a long way from the The Jungle. After Upton Sinclair’s novel detailing the unsanitary and deplorable conditions in Chicago’s slaughter and processing facilities, President Theodore Roosevelt commissioned a report to investigate the meat industry’s sanitation failings.  The 1906 Federal Meat Inspection Act was passed by Congress, after the report’s finding confirmed conditions detailed in The Jungle and public outcry calling for reform (Food Safety and Inspection Service, 2014). Akin to how slaughterhouses have begun to overhaul their image with the help of USDA imposed regulations and public scrutiny, CAFOs should be given the opportunity to do the same.

Knowing that CAFOs cannot be exactly like the animal welfare orientated environment that a well-managed farm can be doesn’t mean that regulations to bring them closer to that ideal are out of the question. Modeling animal health and welfare regulations after those required by farms seeking USDA organic certification (USDA, 2011), CAFOs could improve the management practices that have so far negatively impacted the physiology, immunology, and behavior of swine. Current USDA organic certification mandates high animal welfare standards, taking care of not only the animal’s physical health and needs, but also accommodate the animal’s natural behavior (USDA, 2011).

We propose that all swine should have access to fresh straw bedding at least weekly if not daily, having established that pigs housed without straw bedding have higher rates of joint problems and higher incidence of abnormal behavior. The straw would provide a soft padding on the often-concrete floors of CAFOs and supply environmental enrichment so that pigs can express natural behaviors such as rooting instead of tail biting (Moinard, et al., 2003). We also propose regulations for more space per animal, so that pigs can move around freely.  Giving swine enough room to exercise helps to alleviate joint problems (van Grevenhof, et al., 2011), and creates a more natural environment rather than the overly cramped quarters of CAFOs currently (Moinard, et al.,2003). In addition we propose that the routine use of antibiotics be banned.  Instead, antibiotics should only be used to only treat sick animals. This will help eliminate the problem of antibiotic resistant bacteria in swine and the transference to human hosts. Simple regulation changes like these would make drastic improvements to the health and welfare of swine in CAFOs. Quoting Wendell Berry, the acclaimed environmental activist and farmer, “Though I am by no means a vegetarian, I dislike the thought that some animal has been made miserable in order to feed me.”(Berry, 1990)

            Now the obvious problem with proposing stricter regulations on CAFOs is who will pay for these new regulations. These new regulations will most likely result in an increase in the price of meat. This increase in price will be met with an increase in meat quality, however, because animals that aren’t overly treated with antibiotics, over or malnourished, or sick have a healthier body, which becomes higher quality meat. Physical or immunological stress placed on pigs can cause an increase in acute phase proteins (AAPs) in the meat after slaughter. AAPs are proteins that are associated with inflammation, so their presence in meat after slaughter causes a significant decrease in the quality and value of the meat due to hemorrhaging or bruising (Klauke, et al., 2013). While most consumers will not be thrilled with this increase in price, they must realize that a price increase means that they will receive higher quality meat, and the animals that produce this meat will be treated better.

Why should farmers want to implement these changes, especially when there will be additional costs? Healthier animals mean that fewer animals will be lost to sickness, which means profit loss. More space for animals to roam and straw bedding means less behavior issues like tail biting that eventually result in animal mortality. Think of these new regulations as preventative medicine. They may cost you more up front, but losing your herd to preventable sickness or tail biting will end up costing you more in the end than having replaced straw daily or given more space per animal. A farmer will also save money by using antibiotics sparingly instead of routinely, and saving the time it takes to inoculate your animals. Farmers would increase their profits with these new regulations because more animals would actually make it to market instead of dying of preventable illnesses in their barns.

Another typically argued point is that if CAFOs are really so awful, why not just eliminate them altogether? The simple answer is this: CAFOs feed billions of people yearly, and while there are smaller alternatives that provide more humanely raised livestock, farm policies do not favor these methods. Most policies only benefit large operations that provide cheap feeding and energy costs (Sherman 2008). Whether or not we like it, CAFOs are here to stay as long as the world has demand for meat products, and there is no foreseeable future where that is not the case.

Currently, we rely on CAFOs and factory farms for the majority of our global meat.  Swine CAFOs, however, harm pigs physiologically, immunologically and behaviorally.  Pigs endure physiological damage to their skeletons and joints from increased weight gain, and acute stress can lead to an increase in artificial hormones and stillbirths.  Antibiotic resistant infections are increasing in pigs from antibiotic overuse that can cause permanent immunological defects.  Behaviorally, pigs in restrictive and non-stimulating environments engage in tail biting, which can cause bleeding and infection.  To improve the conditions in CAFOs, the government should impose stricter regulations that require animals be provided with straw bedding, stimulating environments and space to move around and lie down.  While new regulations will increase the cost of meat for consumers, by requiring farms to improve the conditions in which pigs are raised, the quality of meat will improve.  With a global population of 7 billion and growing, we must figure out a way to feed future generations in the safest, healthiest, and most humane way possible.  We are not arguing to abolish CAFOs; we need them in our current population predicament.  We are arguing for a world where CAFOs are no longer the menace but part of the solution to world hunger.



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