Phosphorus for Livestock: Requirements, Efficient Use and Excretion

Keywords: Phosphorus, livestock production, phosphorus sources, phosphorus efficiency, availability, phytase.

Efficient production of livestock and poultry (and fish and pets) and the maintaining the good health of animals requires essential nutrients provided in appropriate amounts that are biologically utilisable. Dietary standards or allowances and thus phosphorus requirements for most animals have been established but are not always well-defined. In order to meet the requirements of the animal and without jeopardising animal health and production the phosphorus recommendations for most animals often include a safety margin and thus unneccessarily high rates of phosphorus are often recommended. Further, phosphorus sources, whether organic or inorganic, frequently have a wide range of bioavailability with those of lowest bioavailability being only utilised to some 50%. As a consequence, in many areas of the world with high livestock and poultry densities, the contribution of animal production to environmental pollution has become a serious issue. Through science-based nutritional strategies, the mineral balance on animal farms can be substantially improved. The bioavailability of both inorganic and organic phosphorus sources must be improved. Inorganic sources with a high digestibility should be chosen and the phytase enzyme should be added to the feed of pigs and poultry. Most of the strategies are quite simple to implement and can have a significant positive impact on profitability. The most promising and practical of these strategies focus on two very simple main principles – minimising input and maximising utilisation without compromising animal performance.

Ingrid E Steén, E-konsult, Ängahusvägen 105, SE-261 76 Asmundtorp, Sweden.

48 pages, 6 figures, 7 tables, 80 references.