A survey of land-use in dairy farms in a grassland farming area

摘要

Land-use system (grazing or harvesting) and its relation to milk yield in dairy farms were investigated in a grassland farming area in Hokkaido. Data of land area, land utilization system, number of cattle, amount of feed purchased and milk production of forty-two farms in eastern part of Hokkaido were analyzed. Total land area of farm positively related to harvesting sward area, but there was no relation between total land area and grazing pasture area or proportion of pasture area. Number of cowsof farm did not relate to total land area. Amount of purchased feed offered per cow and self-sufficiency rate of feed did not related to total land area for production of self-supplying feed (grazing and harvesting). Amount of purchased feed offered percow increased as number of cows per farm increased and, hence, self-sufficiency rate decreased as number of cows increased. Number of cows per unit land area did not relate to amount of purchased feed offered and self-sufficiency rate. Amount of purchased feed offered per cow positively related to milk yield per cow. These results suggested that number of cows and amount of feed purchased did not related to land area of farm, and this means that the land-use system was not considered to be effective for milk production in the grassland farming area.