| The foraging location of in the patch and non-patch area in short term was studied with cattle as experimental animal in the targeted grazing system-Leymus cheninsis meadow. Moreover, foraging strategies of cattle, which was expected to provide theoretical base for theories of foraging behaviour and decision-making gist of grassland grazing manage system, was investigated based on the parameters of foraging behavior such as bite size, intake, intake rate and foraging time. Results of the experiment were as follows: (1) Cattle foraged in the plant patch if there was patch in the plant community. Foraging time was short in the non-patch area because there was a necessary process for animal to adaptive to strange environment. (2) Foraging behaviour of cattle was influenced by the number of patch in plant community. The shift frequency between the patch area and the non-patch area increased with the rise of the number of the patch. However, cattle spent much time on foraging in the patch areas, especially the larger patch when they first entered the experimental plots. (3) Bite size, intake and intake rate decreased with the extension of the patch size in the patch area, but reverse in the non-patch area. But the bite size tended to decrease when the patch area went beyond the limitation of 100 m2. Total foraging bites of cattle increased with the extension of the patch size, but different in the non-patch area and in the patch area. Bite sizes of cattle decreased with the enlargement of patch size in non-patch area, but in the patch area were on the contrary. There were no significant differences for foraging time and bite rate among different experimental plots, which indicating that the foraging time of cattle was relatively stable.(4) Cattle tended to focus on the larger patch when the number of the patch increased, thereby took much time on foraging in larger patch and had the larger bites. Cattle did not foraged on the other smaller patch when the patches exceeded three in short term. Total bite size of cattle in all experimental plots increased when the size of the patch increased as 2.80, 6.86, 6.94 and 8.86g. Foraging time that the cattle spent in different experimental plots was similar. Moreover, the bite rate increased with the rise of the number of the patch and it reached the highest value (0.88b/s) in the plant community with five patches. Intake rate (71.07, 173.84, 217.91, 247.87g) and bite size (1.89, 4.38, 5.57, 7.48g/s) also increased with the increase of number of patch. (5) Bite rate of cattle (0.92b/s) was larger in the plant community with middle-dense and with lower grass patch. And bite rate (0.62b/s) was lowest in the plant community with less dense and higher grass. Bite rate of cattle is highest in the moderate relative biomass of dominant species patch. (6) Foraging strategies of cattle were that the cattle mainly foraged in the patch area, and their foraging time and bites increased gradually with the enlargement of the patch area.Cattle also foraged in other smaller patch besides they more favored the larger patch if there were many patches for cattle to choose. Based on "patch size", the author put forward the foraging strategies of cattle and perfected the theory of RT. (7) In order to increase the intake people should enhance sward density in the course of planting grass and pay attention to uniformity of sward.
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