Submitted to: Proceedings of Babcock Institute Technical Workshop
Publication Type: Proceedings
Publication Acceptance Date: August 1, 2001
Publication Date: N/A
Technical Abstract: There is potential for reducing dietary concentrations of both N and P in dairy diets. The potential for reducing dietary N through more precise formulation of diets for RUP and RDP, and phase feeding or grouping of animals more closely according to production level, will enable reduction of 10-15% of dietary N. This results in about 13-20% reduction in N excretion, and potential reduction of 25-35% in the amount of N lost as NH to the atmosphere. Dietary P levels can be reduced somewhat more, with reductions of 20% or more quite possible. Most, if not all, supplemented P can be removed from lactating dairy diets. Reducing P content of dairy diets by 20% will reduce excretion of P in manure by more than 25%. In addition, the P that is excreted in manure when reduced P diets are fed is less susceptible to field runoff. Improved manure handling, particularly frequent removal from the barn plus field injection or incorporation of manure, will reduce N loses and assist in maintaining a N:P ratio in manur that is closer to crop need.