Poultry manure is the most nutrient-dense livestock manure. The nutrient value is different between egg-laying hens and broilers due to the composition of the animals’ feed. Fresh layer manure usually consists of 2% nitrogen (40 lb nitrogen/ ton manure), while fresh broiler litter typically has a 3% nitrogen composition (60 lb nitrogen/ ton manure). When exposed to the environment, the nutrient composition in poultry manure can degrade rapidly. The leaching of nitrogen, phosphorus, and other nutrients from nutrient runoff can lead to surface water eutrophication, which leads to harmful algal blooms and low oxygen levels where few organisms can survive. Additionally, the volatilization of gases from poultry manure can result in air quality problems. |
With about 2 billion chickens (between broilers, egg-laying hens, and adolescent pullets) in the US at any given time, about 250,000 tons of poultry manure are produced every day. Poultry manure has traditionally been used as a fertilizer and soil amendment for generations. The age-old manure management strategy has been to transport raw manure directly from poultry farms and apply the material - either by broadcasting, tilling, or injecting - to neighboring cropland. However, in areas where large-scale poultry farming has become very concentrated, land application of manure has led to over-fertilization. Widespread manure distribution is limited by transportation costs, so most of the material is spread on cropland less than 100 miles from the sourcing poultry farm.
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