Technology Available

There have been technologies available for handling animal waste for as long as animals have been raised in any degree of confinement. Those technologies have reflected the state of the art as far as development is coincerned and to a great degree the prevailing emphasis on how nutrients contained in the animal waste should be utilized in crop production as a substitute for chemical fertilizer (when available) and as a part of the normal food production cycle prior to availability of chemical fertilizer. The historical literature on the nutrient content of animal manures as fertilizers is extensive and the interested reader is encouraged to investigate that information, recognizing that genetics and understanding of the nutrient requirements of animals have influenced both the input and output of nutrients by animals in ways that make the old data only useful from an historical basis.