If you don't have dairy as an available resource consider eggs. We keep about 300 hens without any commercial hen feed / grain feeds. Their primary job is to organic pest control, we live just up mountain of a marsh. They break apart the manure patties and also eat rodents. A side benefit is they produce tens of thousands of eggs. We feed the eggs to our pigs, concentrating the eggs towards the smaller pigs where we get the most nutritional leverage. By cooking the eggs we double the available protein and help resolve the biotin antagonist problem. In the winter the hens eat pigs, that is meat scraps from our weekly slaughter of pigs. This makes up for the insects they get during the warm season out on pasture.
One of the great things about pigs, and
chickens, is they are omnivores and can eat many different foods. Use the resources you have. Grain isn't evil, just expensive. Thus we don't buy commercial hog or
chicken feed / grain. We do get a little spent barley mash from a
local brew pub (I would love 10x as much) and we get some whey (need about 4x as much). See this page for a break down of what we feed and keep in mind it all varies somewhat with the season and availability. Pasture is our foundation at about 80% of our pigs's diet.
http://SugarMtnFarm.com/pigs
-Walter