Abstract

The intensification of grazing land has increased the amount of nitrogen (N) entering waterways, reducing their quality and clarity. Between 60 and 90% of the N ingested by grazing cattle is excreted in urine and dung (Haynes & Williams, 1993), providing the major source of nitrate leached from grazed pasture. Reducing the N content of urine can therefore have a major impact on nitrate leaching, which can be achieved by reducing dietary N or improving N partitioning in the animal. Some techniques that improve N partitioning have been evaluated. These include dietary manipulation and the use of metabolism modifiers (Di & Cameron, 2000).

de J, Castro, JR Bryant, and VT Burggraaf

Proceedings of the New Zealand Society of Animal Production, Volume 70, Palmerston North, 86-87, 2010