Not now, but it very soon could be a requirement. The USDA is considering requiring that all dairy cows used in producing organic milk be grass-fed during grazing season.
I think this is a great step. Currently, these cows are fed grain that is not treated with pesticides. Grass is what cows naturally eat and what their bodies know how to process. Grain is not as easily digested and because of this, cows fed grain often have stomach ulcers, indigestion and other issues. Because of this unnatural diet, grain fed cattle are often treated with antibiotics to help prevent diseases common among grain fed cattle.
Certainly would be a great step for all — healthier for the cows and for our consumption. Read the entire article here.
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Organic cows should be grass-fed during the grazing season. Also, it should not be that some organic companies currently practice this and some do not yet both are labeled equally organic. Horizon’s and Aurora’s organic milk have been seriously questioned: http://organicelitist.com/2009/01/06/got-milk/
Outside the grazing season, cows should be fed silage (preserved grass and other green growing things), not grain.