Are cows supposed to eat only grass?
Cows originally ate only grass. When herds started to grow, grain was introduced to improve performance and accelerate growth. “When cattle are fed grain, productivity is increased, but fiber-deficient rations can disrupt physiological mechanisms,” said James B. Russell of the Agricultural Research Service, U.S. Department of Agriculture in Ithaca, New York. More research shows that metabolism is enhanced in grass fed diets, which work as an anti-inflammatory, preventing disease and discomfort: “The anti-inflammatory n3 polyunsaturated fatty acids are enriched in grass finished beef (*cattle in general), while higher levels of n6 PUFAs in grain finished animals may promote inflammation and oxidative stress. […] Most importantly, blood cortisol levels strongly indicate that grass-fed animals may experience less stress than the grain-fed individuals.” https://www.ncbi.nlm.nih.gov/pubmed/27185157