Abstract
The pollution of the environment with manure nitrogen is a major argument for improving N utilization and limiting N excretion by animals. The existing legislation covering manure application in the Netherlands is briefly reviewed. In pig nutrition, the need to match more closely the protein supply to the pig's age and physiological state is highlighted - this can result in 6% less N excretion in growing pigs and up to 24% less in breeding sows. In the long term, improving the balance of dietary protein by reducing the total protein content of feeds and supplementing the diets with synthetic amino acids is suggested. Calculations show that reducing the protein content in the diets for growing pigs by 2 percentage units would reduce N excretion by about 25%. (Abstract retrieved from CAB Abstracts by CABI’s permission)