A five-step manufacturing method using broad spectrum hydrolytic enzymes to decompose the volatile fraction of organic waste materials into lower molecular weight, intermediate substrate nutrients to be consumed in turn by selected microorganisms to produce a cellular biomass of microbial cells subsequently harvested for use as a bio-protein feed supplement for farm and domestic animals. A wide range of agricultural, industrial and organic waste materials may be used as the input raw material resource for biochemical processing to bio-protein feed. Applied to the use of cattle manure slurry as raw materials, the biolytic decomposition step employs hydrolyzing enzymes to dismutate volatile organic insoluble high molecular weight proteins, starches, fats, and partially hydrolyzed cellulose compounds into soluble, low molecular weight nutrient intermediates in solution, from which the relatively stable cellulose-lignin solid by-product fraction is separated and dewatered. The Cellular Synthesis step uses selected microorganisms which metabolize and convert these nutrient intermediate products, plus oxygen and nitrogen from air, in their growth and proliferation into a biomass of microbial cells. The biomass is separated and utilized as a single cell bio-protein feed supplement for farm animals. The remaining liquid fraction, mainly water and relatively stable organic matter and mineral salts in solution, may be stored for subsequent irrigation and conditioning of agricultural lands and in the interim may be recirculated for feedlot flushing. The solids by-product, mainly cellulose and lignin, may be used as a fuel or biochemical feedstock or may be recombined with the liquid fraction during irrigation discharge to add mulch-fertilizer soil building values.