In the 1930s, scientists and food producers were creating
the first plans to take poultry off family farms and raise them in confinement.
To enact their plans, they needed to create “feed rations” that would keep the
birds alive and productive even though they were denied their natural diet of
greens, seeds, and insects. It was a time of trial and error.
In a 1932 experiment conducted by the U.S. Department of
Agriculture, breeding hens were taken off pasture and fed a wide variety of feed
ingredients. When the birds were fed a diet that was exclusively soy or corn or
wheat or cottonseed meal, the chickens didn’t lay eggs or the chicks that
developed from the eggs had a high rate of mortality and disease.
But when birds were fed these same inadequate diets and put
back on pasture, their eggs were perfectly normal. The pasture grasses and the
bugs made up for whatever was missing in each of the highly restrictive diets.
“The effect of diet on egg composition.” Journal of
Nutrition 6(3) 225-242. 1933.
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