Nutrient Enrichment in integrated Broiler Production Systems

Broiler litter (manure plus bedding) represents the single largest waste by-product generated by the broiler industry. In 1990, 5.86 billion broilers were produced in the United States (National Agricultural Statistic Service, USDA). On a dry-weight basis, using averages cited in the present paper for litter (1.0 metric ton per 1,000 broilers per flock) and nutrient composition (3.88% total N, 4.25% P2 O5, and 2.68% K2 O), the total annual United States broiler nutrient production is estimated at 227,368, 249,050, and 157,048 metric tons of N, P2 O5, and K2 O, respectively. However, there are substantial variations in both litter production rates and composition values among reports that can greatly influence these estimates. Litter rates and values are influenced by amount and type of bedding, frequency of removal, broiler market weights, nutrition and feed utilization efficiency, and numerous management factors. Understanding these sources of variability is helpful in the implementation of strategies for litter enrichment. In the future, a totally integrated approach may be necessary for the production of litter that is designed for specific applications and markets.