In consideration of climate change, the reduction of resources and the growing population the efficient use of energy becomes one of the key indicators for the development of sustainable agricultural practices. The objectives of this research are to contribute to the development of a method fora generally accepted way of balancing energy in raising livestock. Due to interactions between crop and livestock procedures and between levels of different input factors and their effects on yields, it is proposed to analyze agricultural energy efficiency through system modeling; for that a standard procedure was defined. The energy inputs in raising livestock are assessed on the basis of direct and indirect energy consumption. The energy intensity of the standard procedure amounts to 3.54 MJ per kg of milk. The investigations show that the energy intensity of dairy farming is significantly influenced by feed supply at about 50% and replacements at about 20% of the cumulative energy demand (CED). The CED depends on the site conditions, the yields and the cultivation method as well as the composition of the diet. Increasing pasture in the diet decreases the CED while concentrate in the diet has a reverse effect. Increasing service lives of the dairy cows increase the energy efficiency of dairy farming less than increasing milk yields, at least up to 10,000 kg per cow in a year. The share of the procedure sections milking as well as machines and technical facilities on the CED is 16% and 11%, respectively. The livestock buildings influence the energy intensity only marginally.
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