Economic modelling of an integrated grazed and conserved perennial ryegrass forage production system.

摘要

The Grange Feed Costing Model was modified to simulate the economic implications of grassland management strategies for a grass-based suckler beef calf-to-weanling system at the whole-farm level. The modified model enabled costing of annual grass consumed as grazed grass and silage when the farm grazing and conservation areas are integrated. Grass growth data from sites in the south, east and north of Ireland were used. Sixty-three scenarios were simulated, enabling analysis of site, stocking rate and silage strategy effects on total annual feed cost for the grass forage production system. Total annual feed cost (of grazed grass and grass silage) ranged from Euro 96 to Euro 111 per 1000 UFL (Unite Fourragere Lait) and Euro 411 to Euro 456 per beef cow unit (CU). The silage strategy with respect to the number of harvests and whether the silage area was grazed in the spring had negligible impact on annual total feed cost per CU. However, a tendency towards reduced annual feed cost under a two harvest, relative to a one harvest, silage strategy was observed. The lowest cost stocking rate was 2 CU ha-1. Site-specific differences such as seasonal growth distribution and nitrogen fertilizer response rate had the greatest influence on the annual cost of the grass-based feeding system.