What is the role of pasture in feeding cattle?

Pasture is the most least cost and least labour intensive way of feeding cattle. Pasture is the most natural way possible that cattle can harvest grass themselves without needed human intervention. Pasture would simply become a hay field if humans decided to cut and gather it to feed it to the cattle. Making hay or silage costs more in fuel, fertilizer and labour than having the cattle out grazing the feild themselves. Hay should and only should be made if periods during the year are expected to come that will prevent any further grazing by your herd of cattle. Otherwise grazing pastures, mind you in a way that does not encourage overgrazing, is THE best way to feed cattle ad libitum.