Yes its true that pigs will eat most anything, and convert it to usable meat, however after raising literally thousands of pigs in a variety of situations I have to emphasize the importance of protein in their diet. Without a consistent source of protein it will take them much longer to get to slaughter weight. I think this is what levelfarmer is saying when he says they just wont produce the pork without it. Protein can come from a variety of sources such as soybean meal, fish meal, alfalfa and other legumes, and dairy products. In the past even tankage (discarded meat and by products from slaughtering and rendering operations) was included. It seems as though this practice is much less prevelent today with the rise of prion diseases such as mad cow and scrapie. So go ahead and feed what you want and learn it first hand, just include adequate protein!