SEPATOU, a simulator of grazing srategies, is confronted with the breton 'menus'.

摘要

Grazing simulators are created with a view to assist the farm advisors in the definition and valuation of grazing strategies, because of the difficulty of anticipating the effects of the changes in one or several practices such as nitrogen fertilization or the place of maize silage in spring feeding. SEPATOU is a simulator working through the interaction of two sub-models. The biotechnical sub-model simulates 1/the growth and quality of the herbage, 2/its intake, 3/the milk production. In the decision-making sub-model can be represented: rules for organizing, rules for adapting (to hazards, especially climatic ones), and rules for day-to-day decisions. The simulator's main outputs are grazing and feeding schedules, and potential and simulated production curves. SEPATOU has been tested on three of the typical cattle feeding strategies defined in Brittany, which differ by the place of grazing. The simulation results: schedules of simulated events (turnout date, silo closure...) and grazing schedules (stocking rate and its variations during the year) are briefly described and found consistent with the 'experts' expectations. SEPATOU, by imposing collective clarification and discussion of the rules for decision-making, makes it possible to set up collective representations of grazing management. The rules can be simulated according to different climatic sequences, so that SEPATOU may serve as a learning tool by trial and error. When it is used by a farm advisor with a group of farmers, it will be atool for formation and animation.