Nutrient balance patterns in African livestock systems

摘要: Abstract This paper presents an overview of the current status, problems and prospects for achieving a better nutrient balance to support varying levels productivity from three major livestock systems in Africa. In free range grazing systems, deficiencies are mainly overcome by moving animals areas. makes monitoring managing nutrients within system very difficult. Nutrient recovery, cycling synchronization manure with other recycled or purchased sources greater mixed crop–livestock systems. these inclusion nitrogen-fixing leguminous forage/tree crops as companions rotation cereals further improves use efficiency balance. With more favourable market policies, commercialized dairy developing around urban areas Such heavily depend on feeds nutrients, have serious implications sustainability land rural which supply feeds, because risk pollution accumulating animal wastes.