Feed represents the largest import of nutrients to the farm, followed by commercial fertilizer. Feed management practices impact the amount of nutrients that are imported to the farm and excreted in manure. The excreted nutrients are subsequently available for volatile loss (nitrogen) to the atmosphere and potentially lost via surface runoff (nitrogen and phosphorus) or leached to ground water (nitrogen and phosphorus).
Nutrient management planning addresses the proper distribution of manure nutrients, but typically only focuses on the nutrients after they have been excreted by the animal. It may seem obvious, but the amount of N and P consumed by an animal is directly related to the amount it excretes. Formulating an inexpensive ration with excess N or P, will increase the amount of these nutrients excreted in the manure. Depending on the requirements of the farm nutrient management plan, this may mean that the manure must be spread over a larger number of acres compared to manure that contains lower N or P levels.
Feed management opportunities currently exist to reduce imports of nutrients (particularly N and P) to most animal livestock and poultry operations. Since consulting nutritionists play such a key role with regard to importation of nutrients to the farm, a systematic approach to evaluate the role that Feed Management has on whole farm nutrient management is warranted.
The National Feed Management Education Project (NFMEP) has developed a systematic approach to feed management and whole farm nutrient management. The team has developed a series of fact sheets and resources for the four major species. In addition, the LPE Learning Center Small Farms team has developed resources for small acreage livestock and poultry owners.
Authors: Joe Harrison, Washington State University and Jill Heemstra, University of Nebraska