A model for simulating rule-based management of cow–calf systems

Pastoral livestock farms are complex and dynamic systems, and are subject to many forms of external disturbance. Management strategies can be aimed to minimize system variations in order to control the system and to achieve specific goals. A research simulation model was developed to study the long term dynamics of complete cow-calf production systems for the Salado Region of Argentina. In the model, the operation of the farm is simulated by decision rules entered by the user. The purpose of the model is to assist in the design and evaluation of pastoral beef breeding systems. This paper discusses the model design in detail and an example is then given in which different strategies of hay use during the winter are compared. The results of the simulations were reasonable, indicating the advantages of using hay in reducing the variability of system productivity, but the different patterns of hay use did not show any impact on the long run performance. The design principles used give considerable flexibility, so the model can be used to simulate and study management combinations available to the farmers.