Studies on the feeding strategy of grazing animals in the spatially heterogeneous vegetation

对空间异质性植被中放牧动物的取食策略进行了一系列研究，主要集中在斑块尺度上的牛对热带草地的取食。放牧牛的斑块选择在2 ~ 9块不同复生期和施肥量的样地上进行。实验表明，动物有能力从许多提供的斑块中识别出最喜欢的斑块，通过两个阶段的选择，在参观和在斑块中居住。咬伤尺度和短期摄取率对放牧热带草地的牛的咬伤尺度和短期摄取率与草地高度和质量的关系进行了量化和建模。该模型可用于patch选择的定量奖励估计。动物斑块选择建模与选择奖励识别利用野外数据建立了动物斑块选择模型。结果表明，该模型具有足够的预测能力。斑块选择的定性奖励确定为粗蛋白浓度。动物之间的取食策略差异动物之间取食地点的选择是不同的。需要进一步的研究来评估这种动物间变异的生态学意义，并将这种机制纳入以群体为基础的喂养模型。

A series of studies were conducted on the feeding strategy of grazing animals foraging in the spatially heterogeneous vegetation, focusing mainly on the patch-scale feeding by cattle on tropical grass swards.1. Patch selectionPatch choice by grazing cattle was studied in plots comprising two to nine patches differing in regrowth period and fertilizer rate. The animals were shown to have an ability to identify preferred patches from many offered patches, through the two-stage selections at the visit and during the residence in patches.2. Bite dimensions and short-term intake rateBite dimensions and short-term intake rate in cattle grazing tropical grass swards were quantified and modeled in relation to sward height and mass. This model can be used for estimating the quantitative reward of patch selection.3. Modeling patch selection by animal and identifying the reward of selectionA model of patch selection by animal was developed using field data. The model was shown to have sufficient predictive ability. The qualitative reward of patch selection was identified as crude protein concentration.4. Animal-to-animal variation in feeding strategy Selection of feeding location varied from animal to animal. Further studies are needed to evaluate the ecological meaning of such animal-to-animal variation and to incorporate this mechanism into a feeding model on a herd basis.