In the framework of the current revision of the Swiss Fertilizer Guidelines (SFG) the guide values for nutrient excretion of pigs were checked and adapted to current production practice. The principle used for calculating excretions is input in feed minus retention in in the growth of piglets and young sows. For fattening pigs all the relevant information on current production practice could be derived from representative farm data. For sows, in addition to analysed farm data information was derived from the current feeding recommendations. For the feed content, the mean values for normal feed without reduced protein and phosphorous content from a representative survey was used for all animal categories. For fattening pigs the nitrogen (N) and phosphorus (P) excretions which are important for the compulsory nutrient balance of farms remained practically the same as according to the previous guide values. This was possible because the increased productivity per place per year was counterbalanced by a better feed conversion efficiency and a reduction of the protein and P content of the feed. For sows excretions increase quite considerably because of the higher productivity (piglets per sow per year, shorter suckling period etc.) and changes in the feeding recommendations.
New guide values for the nutrient excretions of pigs