Grazing behaviour, diet selection and feed intake of cattle in a young tree plantation in southern Kyushu, Japan

Grazing behaviour, diet selection and feed intake of cattle grazing a young Chamaecyparis obtusa (an evergreen conifer) plantation in south-western Japan were monitored for 4 years to develop an understanding of animal-vegetation relationships in forest grazing. Animals spent 439-647 min per day grazing, with the activity being high during 06:00-10:00 h (after dawn), 10:00-14:00 h (around midday) and 14:00-18:00 h (before dusk) and low during 22:00-02:00 h (around midnight) and 02:00-06:00 h (before dawn). Although animals were observed to eat 118 species or species groups ( 11 herbaceous species or groups, 33 lianas, 73 shrubs and trees, 1 fern group), most of the bites (71-97%) were taken from 10 species or species groups, showing grasses (mainly Miscanthus sinensis; 27-74%) as the most selected plants. Despite the high selectivity, grasses showed relatively low dry matter digestibility (453-485 g/kg DM) and crude protein (CP) concentration (96-120 g/kg DM) among the major species or species groups. Dry matter digestibility and CP concentration of the diet were estimated at 427-587 and 70-150 g/kg DM, respectively. Feed intake by animals ranged from 1.42-2.12, 0.64-1.21 and 0.11-0.29 kg/100 kg LW/d for DM, digestible DM and CP, respectively. Selection by animals of a wide range of browse species (trees + shrubs, lianas) was interpreted as a behaviour to complement the low quality of the grasses, which represented the majority of the diet.