A few stats to give you pause:
I go through nearly 300 pounds of chicken feed per day. That number will probably triple/quadruple in a month or two when I have broiler chickens on pasture. Fortunately, my feed supplier allows me to contract grain at a fixed price for a 3 month period, though the price of grain has been climbing steadily every week since I started the farm 2 years ago.
Suffice it to say, I spend a lot of time thinking about ways to pull this operation off dependency on the commodity grain market.