Production of Eisenia fetida and vermicompost from feed-lot cattle manure

Significant reductions in total mass of feedlot cattle manure were obtained by the intensive activity of earthworms. The process yielded two products: residual vermicompost, and an increase in earthworm biomass. Various modes of manure application were made to a prepared bedding (or support material), the most successful being a surface (vertical) application which resulted in a reduction of 30% of the initial manure (dry) mass and the production of live earthworms to 4.9% of the initial manure mass (dry weight). The increase in earthworm biomass represented extraction of, respectively 7, 18, 7 and 2% of initial total C, N, S and P from the manure. The production of vermicompost from manure resulted in a pH shift toward neutral, a reduction in electrical conductivity, large increases in oxidation potential, and significant reductions in water-soluble chemical species which constitute possible environmental contaminants.