放牧牛の生理・生態に関する研究(II-12) : 自然牧野における野草エネルギー生産量とGrazing capacityの時期的変化について

Seasonal changes of the grass yield and the chemical composition were investigated on native grasslands during the grazing period extending from May to November. The grazing capacity of the grasslands was computed from estimated energy production, and the energy expenditure which had been already decided in grazing cattle. The principal results obtained were as follws:
1) The grass yield reached a maximum, 211kg/10a on the dry basis, in July, on the other hand, a minimum yield was 53 kg in November.
2) Chemical compositions of the grass changed with the progress of season, and it caused a decrease in crude protein from 12.3 to 8.8%, and a increase in fiber from 27.3 to 33.0%.
3) Maximum grazing capacity of this grasslands could be estimated as 0.91 head for 120days grazing on the condition of the grass in July, whereas estimated as only 0.26 head in November.