A simulation model representing the dynamics of a sow farm is presented in contrast with other approaches. To highlight relevant aspects of the model a real application for planning piglet production is considered. The main contribution of the model is that sow herd management is based on batches of sows being in the same reproductive state, as actually is done in practice. This features allow to measure the discrepancy with other approaches and comparing different reproductive management strategies in a more realistic way than by using other quantitative methods. Furthermore, the implementation in Extend allows potential users to perform efficiently different kinds of analyses tracking variables of their own interest.