A typical cow weighs 1500 pounds and produces 70 pounds of milk per day. A cow converts roughage and grains not consumed by people into high-energy foods.
One day's production is equivalent to:
3.3 pounds of butter, or
8.1 gallons of milk, or
7 pounds of cheese.
One day's consumption is about:
35 gallons of water, and
20 pounds of grain and concentrated feed, and
35 pounds of hay or silage.
--American Farm Bureau Federation's Food and Farm Facts