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The economic evaluation of forage maize is complex due to its usage in different types of farms as well as the interdependencies of forage maize traits with the farm organization and the intensity of production. By means of linear programming, the economic weights of important forage maize traits were calculated for farming conditions in Germany. They were determined from the difference in the gross margins of farm models for given changes in a single trait of forage maize and were calculated for dairy and bull-fattening farms under five levels of animal performance, three stocking rates, and different levels of forage maize traits. Individual economic weights under these settings varied little in most cases and allowed aggregation of mean economic weights. They amounted to 4.6 ECU ha?1 for metabolizable energy yield (GJ ha?1), 207 ECU ha?1 for metabolizable energy content (MJ kg?1), and 3.1 ECU ha?1 for crude protein content (g kg?1). Economic weight for forage dry matter content was strongly dependent upon the maturity of the materials and varied between -5 and 25 ECU ha?1. The application of economic weights was discussed in comparison with other criteria for the assessment of experimental hybrids in official trials. 相似文献
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