In the 20th Century, much of America’s livestock production went indoors.  Efficiency and labor reduction were the main drivers of this move.  But what about the quality of the product or the effect on the animals themselves?  Recent research has tried to answer these questions.  Clear evidence is emerging that the shift to concentrated indoor production systems has had poor outcomes for both our food and the animals that produce it.  A sampling of peer-reviewed scientific studies is provided here.

Effects of Outdoor Housing of Piglets on Behavior, Stress Reaction and Meat Characteristics

This paper discusses the effects of stress and housing system.  It concludes that outdoor-reared pigs exhibit lower physiological symptoms of stress.  

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Sun exposure in pigs increases the vitamin D nutritional quality of pork

This study shows that outdoor pig production can increase the amount of Vitamin D in the pork by 300%.

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Effects of three husbandry systems on health, welfare and productivity of organic pigs

This paper evaluates pork from indoor, outdoor, and mixed organic hog farms and concludes that outdoor systems “appeared to have advantages,” even though all were using approved organic practices.  

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Vitamins A, E and fatty acid composition of the eggs of caged hens and pastured hens

This article compares the levels of Vitamins A & E, along with omega-3 fatty acids in pasture-fed hen’s eggs versus conventional eggs.  

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Fatty Acid and Antioxidant Composition of Conventional Compared to Pastured Eggs: Characterization of Conjugated Linoleic Acid and Branched Chain Fatty Acid Isomers in Eggs

This article evaluates the amount of healthy fats in pastured eggs and confinement eggs.  

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