Potential for Recycling Animal Wastes by Feeding to Reduce Environmental Contamination

Animal wastes were regarded as valuable sources of plant nutrients in the early part of this century and were used extensively as fertilizer. Following the introduction of intensive confinement systems during the past 40 to 50 years animal wastes became a liability rather than an asset. This change in perceived value of waste resulted from the availability of low-cost commercial fertilizer and the high cost of handling and transporting the wastes. Animal wastes were identified as a concern in the control of water, soil, and air pollution (Freeman and Bennett, 1969).