Dietary Specialization in Mammals: Tests of Detoxificaton and Elimination Models

9809961恐惧症哺乳动物食草动物生态学研究的一个基本目标是确定限制饮食专门化的生理因素。虽然植物次生化合物在哺乳动物食草动物食物选择假说的形成中起着至关重要的作用，解毒能力也经常被认为是决定食谱广度的机制，但我们对草食动物如何解毒次生化合物的了解相当有限。为了建立更具预测能力的食物选择模型，并了解食草性哺乳动物的生态分布，我们首先需要提高我们对哺乳动物解毒系统的了解。拟议研究的目的是通过测试以下3个假设来确定和量化专家和多面手食草动物用来解毒植物次生化合物的机制：通过产生比多面手产生的酸性更少的解毒代谢物；通过在解毒过程中产生与多面手相同的酸负荷，通过与多面手完全不同的途径消除在这一过程中产生的氢离子(H+)；以及具有比多面手更大的缓冲尿液的能力。

9809961 Dearing A fundamental goal in the study of the ecology of mammalian herbivores has been to identify the physiological factors that limit dietary specialization. Although plant secondary compounds have played a paramount role in the generation of diet selection hypotheses of mammalian herbivores and detoxification capability is often proposed as a mechanism determining diet breadth, our understanding of how herbivores detoxify secondary compounds is quite limited. To generate diet selection models with more predictive power and to understand the ecological distributions of herbivorous mammals, we first need to improve our knowledge of the mammalian detoxification system. The objective of the proposed research is to identify and quantify the mechanisms that specialist and generalist herbivores use to detoxify plant secondary compounds by testing the following 3 hypotheses: by producing detoxification metabolites that are less acidic than those produced by generalists; by generating the same acid-load during detoxification as generalists, however, eliminating hydrogen ions (H+) produced in this process through an entirely different route than generalists; and by having a greater capacity to buffer urine than generalists.