An Integrated Approach to Managing Nitrogen on Dairy Farms: Evaluating Farm Performance Using the Dairy Nitrogen Planner

摘要: Nutrient flow in dairy farming involves animal and field components that are linked by transfers of crops manure. Connections the farm to surrounding environment created inputs outputs feed, fertilizer, biological N 2 fixation, animals products, nutrient losses air water. Because these linkages among connections environment, an integrated system-level approach would be useful evaluate performance terms production efficiency environmental protection goals. The purpose this study was management comparing data with reference values from Dairy Nitrogen Planner (DNP), spreadsheet planning evaluation tool. Performance were two Pennsylvania dairies: Farm 1, 109 lactating Holstein cows (Bos taurus), forages produced on 92-ha crop land supplemental feeds purchased as directed nutritional services; 2, 65 cows, nearly all 111-ha no forage quality analysis or ration formulation assistance. performances 1 respectively, (with difference relative DNP projection): annual input, 17 450 kg (-5%) 10 670 (-10%); milk-N output, 3880 (-8%) 2790 (-0.4%); feed-N intake, 20 200 (-2%) 18 820 (+1%); manure for application, 8550 (-14%) (+11%). differences between projections identified overall organization opportunities improved system 1. Animal balancing a priority area enhancement subsequent action adopt services professional nutritionist increasing milk 20% decreasing 10%.