Profit stability of mixed dairy and beef production systems of the mountain area of southern Auvergne (France) in the face of price variations: Bioeconomic simulation

Mountain farmers face additional structural constraints (e.g., steep slopes, high elevations, fragmented fields) along with the regular risks inherent to agriculture, such as economic fluctuations. We thus hypothesized that simultaneously producing dairy and beef herds (i.e., "mixed cattle systems") on mountain farms is a good compromise between a farm's expected profits and the variation in these profits. To explore the profit stability of mixed cattle systems in the face of price variations, we used the bioeconomic optimization model Orfee to simulate one farm strategy: adjusting the number of cattle. The model simulated three mixed cattle systems (dairy and beef herds) and two specialized cattle systems (dairy or beef herd) on two farms in southern Auvergne (France) that differed in agronomic potential, field configurations and animal productivity. A local sensitivity analysis of beef, milk and feed price was combined with a global sensitivity analysis based on metamodels. Results indicated that the number of cattle was adjusted as a function of resource availability, farm structure, and product prices on the market. Compared to specialized systems, mixed cattle systems usually seemed an effective strategy to manage economic risk, with good compromise between expected profits and variation in profits.