Excerpts from the report: Growing-finishing hogs digest about 85 percent of a corn-soybean meal ration. The remainder of the nutrients plus most of the minerals are excreted. Farmers have traditionally used these wastes for fertilizing cropland. Problems of odors and runoff, the relatively low cost of commercial fertilizers, and the increasing size of hog enterprises relative to holdings of cropland have now reduced the attractiveness of this practice. This report presents an evaluation of feeding aerobically digested hog wastes compared with other systems of storing and handling liquid wastes from hogs grown and finished in confinement. Confinement denotes a totally enclosed hog building with slotted floors and pit storage for the wastes. The feed replacement values of aerobically digested hog wastes were based on research in process and can only be termed “best estimates." Equipment for collecting, processing and feeding the material is in the experimental stage. Nevertheless, an economic analysis based on "best estimates" provides clues to the general magnitude of probable costs and benefits and strengthens the need for additional research.
