|Wu, Z - UNIV OF WISCONSIN MADISON|
Submitted to: Cornell Nutrition Conference for Feed Manufacturers
Publication Type: Proceedings
Publication Acceptance Date: October 21, 1999
Publication Date: N/A
Technical Abstract: Public scrutiny of the impact of agricultural practices on the environment is growing. The livestock and poultry industries have been targeted for attention because of their visibility, and for real as well as perceived abuses. Large concentrations of animals in relatively small areas create difficult challenges in terms of odor and nutrient management, but problems sof nutrient management can plague small as well as large animal operations One of the fundamental challenges facing the livestock/feed industries is to recycle the flow of feed nutrients, particularly phosphorus and nitrogen, from animal operations back to cropland where they can again be used for crop production. The days are numbered for simply disposing of manure. It is likely that in the near future manure application to cropland will be restricted to the amount of nutrients that can be utilized by the crops. Phosphorus content of manure will likely be the determining factor for the application rate of manure, since the P:N ratio in manure is approximately twice the P:N ratio needed by crops. We can reduce dietary phosphorus in dairy diets from approximately .48% to .38%. This will reduce phosphorus excretion in the manure by 25-30%. This-translates into 25-30% less land required for manure disposal. A strategy of reducing dietary phosphorus levels is a win-win situation for dairy producers, since both feed costs and environmental risk/cost of manure disposal are reduced.