Reducing whole-farm surpluses of phosphorus and potassium in intensive livestock operations:


Source: University of Manitoba

A case study of dairy farms


Project Leader:  Dr. Kees Plaizier, Dept. Animal Science, Email:
Co-Investigators: Dr. Kim Ominski (U of M), Dr. Don Flaten (U of M), Rob Barrie (MAFRI), Clay Sawka (MAFRI)
Industry Partner: Dairy Farmers of Manitoba




The goal of this study is to identify and develop BMPs that will enable dairy farmers to:
1) comply with the P-based manure management regulations, without compromising productivity and
2) reduce the accumulation of K in soils and forages in the farm that could otherwise jeopardize the health of dairy


The main objective is to develop whole-farm/whole-system BMPs for farmers to maintain soil phosphorus at environmentally sustainable levels within manure management regulations and, where possible, to reduce potassium surpluses.

BMPs will target co-reduction of nutrient imports, improved on-farm nutrient cycling (through manure and feed crops), and enhanced export of excess P to aid farmers in the transition to P-based manure application regulations.


This project is a case study of 10 Manitoba dairy farms that represent a range in nutrient import/export:
1) import of all feedstuffs (concentrate and forages),
2) import of concentrates with most forages produced on-farm, and
3) all feedstuffs produced on-farm where possible.
Selected farms will also represent different housing and manure handling (both free-stall and tie-stall) and perennial/annual cropping systems, including growing commercial crops for export.

Download Final Report here (pdf)