The energetic feed evaluation in Germany.

The paper describes the energetic feed evaluation systems for ruminants, pigs, poultry and horses presently used in Germany. During the last ten years the "Ausschuss für Bedarfsnormen" (AfB; Committee of Nutrient Requirements) of the "Gesellschaft für Ernährungsphysiologie" (GfE, Society of Nutritional Physiology) introduced new recommendations for energy requirements of domestic animals including national and international references. The energetic requirements were factorially deduced (demand for maintenance and various performances) under consideration of partial efficiency of utilized metabolizable energy (ME) for various performances (k-values). Except for lactating cows (Net Energy Lactation; NEL) the energy requirements of other ruminants as well as of pigs and poultry are given in ME. At present, the energy requirement of horses is still expressed as digestible energy (DE). Besides several energy requirements reported there are equations to determine and to calculate the energy content of feeds (GfE, 1986-1998) and corresponding tables with include the nutritive values of feedstuffs for various species. The energy content of mixed feeds may be estimated by specific equations.