LiGAPS-Dairy

LiGAPS-Dairy is a generic, mechanistic model to assess potential and feed-limited milk production in different dairy production systems across the world. The model uses concepts of production ecology to simulate potential and feed-limited production, and is developed from the model LiGAPS-Beef (see https://models.pps.wur.nl/ligaps-beef). LiGAPS-Dairy consists of a thermoregulation sub-model, a feed intake and digestion sub-model, and an energy and protein utilization sub-model. Energy and protein flows are simulated. Milk production is simulated based on the defining growth factors (genotype and climate) and limiting growth factors (feed quality and feed quantity). The defining factor climate affects milk production and growth via heat stress and cold stress. The limiting factor feed quality is further split up in limitations in digestion capacity and protein deficiency. The limiting factor available feed quantity is split up in energy deficiency and protein deficiency. The model can be used to assess yield gaps in dairy production systems, to analyze yield gaps and to explore options for yield gap mitigation and improvements in resource use efficiency.