| This research is a creative work which studied the behavior patterns, rules and production of grazing cattle in the whole year. Meanwhile, the grazing system of Carex and Leymus chinensis meadow was taken as research object, the foraging behavior, vegetation characteristics and the ability of grass growth were studied by controlled grazing in plots at different stock rate The study of grazing cattle manifested that the behaviors rules and regulation mechanism and the response of grassland .(1) In the condition of free grazing, the average daily intake time of the grazing cows was 293.2 # 134min, daily ruminating time was 22.6 # 28.0min, daily resting time was 21.3 #31.1min, daily standing time was 14.3 # 11.8min, daily walking time was 70.1 #23.0 min. When the grazing time was short, grazing cows tried to keep the foraging time respectively stable by shortening the ruminating time. And they also tried to keep the respective stabilization on rate of intake and daily mount of foraging by regulating the parameters of foraging behaviors.(2) The rate of intake cows' foraging in spring, summer, fall and winter were 58.0#13.0 bite/min, 52.5#10. 7 bite/min, 45.1#18.6 bite/min and 47.9#15.7 bite/min. The range order on amount of intake per bite in whole year was: fall>summer>winter>spring, the respective amount was 567.8 mg/bite, 375.3 mg/bite, 366.7 mg/bite and 281.7 mg/bit. The amount of intake in one day was: fall>summer>spring>winter. The respective amount of dry biomass per cow pick up everyday was 10.45 kg, 8.10 kg, 7.34 kg and 5.31 kg.(3) The pastures which had good palatability in July included Setaria viridis, Chenopodium acuminatum and phragmites australis, the species of indulgence intake and enjoy intake occupied 27 per cent in the total species they picked up. The pastures which had good palatability in August included Setaria viridis, Leymus chinensis , phragmites australis,Cannabis saliva, Digitaria ischemum and Potentilla tanacetifolia . The species of indulgence intake and enjoy intake occupied only 50 per cent in the total species they picked up.(4) The diurnal ruminating cycle in summer mostly appeared in the mornings while that in the other seasons appeared in the time of noon break. The diurnal ruminating difference between different seasons was the result of the effect, which was caused by the climatic factor, grass condition, and the grazing system. The ruminating behavior took place mainly in nights under the grazing system that claimed out in the morning and back in the night, the effect that seasons gave to the ruminating behavior was substantially the effect caused by the difference between pasture's quality and pasture's amount.(5) The amount of intake and the amount of intake per bite, the intake rate were positive correlated extremely significant. (r=0.954, 0.987), and eating speed positive correlated significant (r=0.692) , and bites per step negative correlated significant (r= -0.576) . The regression equation of intake speed and amount of intake was y=-0.025x3+4.3678x2-252.71x+4859.7. Bites per step played certain function to the regulation of picking amount. The regression equation of them was y=-0.0135x3+0.7758x2-l4.902x+104.01. The grazing cow would finally regulate the daily picking amount through eating speed. The regression equation of them was y=0.2306x09972. The intake per bite was the basic regulate factor for the variation of which was prevailing in the grazing behavior. The regression equation of daily amount of intake and the amount of intake per bite was y=14.129x1.139.(6) The height of grass layer was significantly positive correlated to amount of intake, intake per bite and intake rate (r =0.500, 0.612, 0.533 ) .was significantly negative correlated to intake rate (r= -0.567 ) . When the height of the grass layer was 16cm or so, the time limit amount of intake reached or approached the highest level. The DM was 12.31kg/4h. If that was higher or shorter than this height, the amount of intake appeareda downtrend. The...
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