USING MODELS TO ESTIMATE SHEEP VOLUNTARY INTAKE ON PASTURE-BASED SYSTEM
planning farm, small ruminant, forage budget
The models (theoretical, conceptual, physical, mathematical) can be used to describe and understand a system. With this information, it is possible to predict, simulate and estimate responses of the modeled system in situations, for example, very onerous or difficult to measure. For these reasons, the objective of this research is propose an application that use models to estimate sheep voluntary intake on pasture-based system on forage budget and planning the strategies of the use of forage. For this, it were created da database with information of animal (Live weight, reference weight of an adult animal, average daily gain and consumption) and pastures (forage mass before and after grazing) from scientific journals, dissertations and thesis that has this data. It was used two models, named model 1 and 2. The model 1 estimate sheep voluntary intake as a function of animal live weight (kg/head) and live weight gain (Kg / head / day) . The model 2 uses the same variables than the 1 and, in addition, use the reference weight of adult animal to estimate voluntary intake. The results using model 1 had not significant differences with the database used to perform it. On the other hand, it not occurred when the model 2 was run using the same database. Therefore, was used model 1 estimate the forage budget and sheep production planning on a pasture-based system.