Alternatives in Animal Waste Utilization-Introductory Comments

Animal wastes represent a valuable resource if utilized properly. Approximately 2 billion metric tons are produced annually in the United States (Wadleigh, 1968; Heichel, 1976). In the past, the wastes were used mainly as fertilizer and were important in the development of agriculture. With the development of an efficient fertilizer industry, supplying plant nutrients from commercial fertilizer became more economical than from animal manures due to the cost of collecting, hauling and spreading the wastes. Furthermore, large concentrated livestock enterprises such as the Southwest cattle feedlots and Southeast broiler operations were developed on small areas of land. Thus, availability of land for spreading the wastes became a problem. The wastes from the large concentrated operations became a nuisance and a source of pollution, especially since some of these were in close proximity to municipalities, lakes and streams. If the wastes are not handled judiciously, health problems may be encountered since the wastes may contain pathogenic organisms (Bhattacharya and Taylor, 1975).