Abstract
1. The purpose of this study was to estimate the productivity of sward by the livestock performance with different grazing intensity. 2. The stocking rate tested in this study were 2.50cow/ha for control (treatment 1) and 3.125cow/hr for heavy grazing intensity (treatment 2). 3. The pastures used were 2.0ha for treatment 1 and 1.6ha for treatment 2, and both of them were divided into 4 paddocks. Five lactating cows were assigned to each treatment. The rotational grazing system was taken with a basis of the grazing condition of the control. The surplus grasses of each pasture were made in hay and were given to the cows which were fed concentrate at a rate of 20% of milk yield. 4. The daily amounts of FCM produced per cow were 14.68kg. In average for treatment 1 and 14.23kg. for treatment 2 which was 25% greater in grazing intensity than that of treatment 1. Calculated yields of FCM per hectare were 5.44t. for treatment 1 and 6.54t. for treatment 2 which was 20.2% greater than that of treatment 1. This increase shows that productivity of psasture estimated with milk yield has been influenced by heavy grazing intensity. 5. There was no significant effect of grazing intensity on milk composition and weight gains of the animals. 6. Yield of TDN per hectare in treatment 2 was.18.3% greater than that of treatment 1 (4.08t. vs. 3.45t). This result suggsts that an increase in grazing intensity improved an efficiency of a pasture utilization. 7. From the results of the past two years' studies on grazing method, it was also showed that increasing graziug intensity tended to improve the productivity per unit area of pasture, although the production per cow was slightly decreased.
