OVERSEER calculates nutrient intakes for an animal enterprise by first calculating the energy requirements for the enterprise using a standard metabolic model (Animal metabolic energy requirements chapter). This is converted to dry matter (DM) intake based on the feed from different sources consumed by the animals and default values for their metabolisable energy (ME) contents. Based on the DM intakes and nutrient contents of the different feed sources, nutrient intake is calculated. The reasons for using this method, rather than using pasture DM production and utilisation are outlined in the Animal model chapter.
The Animal Intakes Technical Chapter can be found here