Food Safety Magazine, February/March 2013

Percent (between 0 to 1) / $100 spent0.120.10.080.060.040.020Fruits andvegetablesDairyproductsEggsFish andseafoodBeef, pork,poultry, andother meatsBeef Pork PoultryFigure 1: Percent of Foodborne Illnesses Traced to Food Groups per $100 Spentshould be treated, we are also debating the safety of our food. In the next section, weexplore the ways in which animal well-being can be improved and the concomitantchange in food safety we should expect.Natural Animal Behaviors and Safe FoodAnimal scientists and consumers often have different notions about what makesfor a happy animal. According to many animal scientists in the U.S., high welfare primarilyrequires a clean, healthy environment where animals are provided with all theirphysiological needs, are provided adequate shelter and are protected from predators.According to this perspective, there are synergies between animal welfare and foodsafety, as both can be provided in the same environment.According to our survey work, roughly 40 percent of Americans agree with this perspective(another 11 percent say they care little about the well-being of farm animals).This leaves 48 percent of Americans who disagree with our depiction of the animalscientists’ view, and believe animals must also be allowed to exhibit natural behaviorsif they are to experience high levels of well-being. 9 These behaviors include the abilityto move around freely, access to the outdoors and the opportunity to socialize withanimals of their species.Allowing free expression of natural animal behaviors should reduce stress in theanimal, and as a consequence may 10 (but may not 11 ) reduce the shedding of pathogens.12 These improvements, however, often come at a cost. Layers raised in a cagefreesetting can suffer from injury by other hens, creating stress and even death. Sowsmoved from a gestation stall into a group pen can now turn around freely, but mayturn to encounter an aggressive sow—again, creating stress. We once visited a free-rangeegg farm where the birds had access to pasture but were continually preyed upon byhawks—this fear would certainly create stress. While there is no guarantee that theseimprovements are good for animal welfare or food safety, most published researchcontends that replacing battery cages with cage-free systems (or enhanced cages) 13and converting gestation stalls to group pens 14 improve animal welfare. And if animalwelfare is improved, it is reasonable to believe stress and the shedding of pathogensare lowered—but there are no guarantees. We once talked to an egg farmer raising bothcaged and cage-free eggs, and his employees would not eat the eggs from the cage-freesystem, believing the difficulty of identifying and culling sick hens in a cage-free systemmakes the average egg more risky to eat.The relationship between animal well-being and food safety becomes more complexwhen a farm uses a free-range system, where animals have access to both comfortableshelter and the outdoors. Hogs love mud, and mud is rarely sterile. Hogs eagerlyroot and engage in continuous social interactions. While such a “natural” setting islikely to increase animal well-being in one dimension, it may also make a hog sick, ashogs can more easily come into contactwith the feces of other hogs and wildlife,as well as a broad array of worms andother parasites not normally found ona concrete floor. Increased prospects fordisease, infection and parasites can turn ahappy hog into a sick hog.One of the original motivations forconfining hogs to concrete floors insidebuildings (i.e., today’s conventional hogfarm) was to separate hogs from parasitesand pathogens. Lungworms wereonce found in at least one-half of hogsin the 1940s, but today the parasite is ararity. The same can be said for kidneyworms. Pork was once thought dangerousto eat if undercooked. The threatwas trichinosis—another threat that istoday almost nonexistent. 15, 16 Farmersonce deliberately raised hogs in the samepastures as cows, knowing hogs wouldeat undigested grain from cow feces.Chickens would do the same. 17 An eggstudy found greater Salmonella contaminationin free-range eggs, probably dueto the easy access rodents have to thechicken feed. Not only do the rodentsdefecate in the chicken feed, but “micedroppings can be actively sought outby birds when mixed in the feed and orbedding because of their seed-like sizeand appearance.” 18 However pleasant thesmall, diversified farm seems, most consumersdon’t like to eat animals that atethe feces of other animals. Farmers didnot confine animals to cramped cageson hard floors out of malevolence butto reduce parasites and disease. Animalwelfare may be compromised by confinement,but animal health is improved,and with it food safety.Comparing hog health today with 70years ago isn’t an entirely fair comparison.Given the scientific advancementsin animal production since the 1940s,it might be possible to allow hogs outdooraccess without the concomitantpathogens and parasites experienced bythe 1940 farmer. Yet even today, researchfinds that hogs given outdoor accessexperience higher rates of Salmonella,Toxoplasma and Trichinella than hogson conventional farms. 19, 20 In outdoorsystems, Salmonella is spread throughsows’ wallowing in the same mudhole, 2150 F o o d S a f e t y M a g a z i n e