Abstract
This investigation was conducted to clarify the daytime behavior of grazing cattle herd on the pasture, particularly of the resting form, as a part of analysis of pasture ecosystem. Holstein and Aberdeen Angus breed were used for this investigation. To analyze the resting form of grazing cattle herd, we defined resting ratio and laying ratio as follows: Resting ratio (%)=<resting cattle numbers>/<total grazing cattle numbers>×100 Lying ratio (%)=<lying-down cattle numbers>/<resting cattle numbers>×100 1) According to the investigation of seasonal variation, the highest resting ratio was shown in midsummer, followed by spring and fall. On the other hand, lying ratio showed the lowest value in midsummer. 2) It was recognized that lying ratio showed a tendency to decrease as the environmental temperature was getting higher. 3) With appearance and activating of parasitic insects, especially of horseflies, lying ratio decreased remarkablly and there was recognized a significant negative correlation between activity of parasitic insects and lying ratio. 4) A significant negative correlation was recognized between daily gain of body weight and resting ratio, while a significant positive correlation was recognized between daily gain and lying ratio. In these facts, the author disccused on the relationships between resting form of grazing cattle herd and environmental conditions. 5) From the results described above, the author classified the resting form of grazing cattle herd into five types according to the environmental conditions.
