International Research Fellowship Program: Mechanisms for Increased Intake of Toxic Plants by Marsupial Herbivores

0301898索伦森国际研究奖学金计划使美国科学家和工程师能够在国外进行三到二十四个月的研究。 该计划的奖项提供了联合研究的机会，以及使用国外独特或互补的设施，专业知识和实验条件。 该奖项将支持博士詹妮弗S。索伦森与澳大利亚国立大学的威廉·J·福利博士和塔斯马尼亚大学的斯图尔特·姆克林博士合作。食用单一植物物种的哺乳动物（10种）的缺乏被归因于这种饮食中存在的高浓度植物毒素。 很少有实证工作进行了审查机制哺乳动物草食动物雇用，以科普植物毒素。 该项目将涉及研究毒素吸收在哺乳动物食草动物摄入有毒植物中所起的作用。 通过测量专家（考拉）和多面手（刷尾负鼠和山刷尾负鼠）喂养的有毒植物桉树的毒素摄入量、血液毒素浓度和粪便毒素排泄量，来检验饮食专家比多面手每摄入单位吸收更少毒素的假设。 据预测，专家对毒素的吸收较低将导致更大的毒素摄入量，但血液中的毒素浓度较低。 PI在Neotoma属中发现了专家比通才吸收更少植物毒素的证据，并且拟议的研究将通过比较毒素吸收以及不同家族的专家和通才哺乳动物食草动物之间介导毒素吸收的机制来进一步扩展这些结果。

0301898SorensenThe International Research Fellowship Program enables U.S. scientists and engineers to conduct three to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twenty-four month research fellowship by Dr. Jennifer S. Sorensen to work with Dr. William J. Foley at the Australian National University and Dr. Stuart McLean at the University of Tasmania.The paucity of mammalian herbivores (10 species) that consume a single plant species has been attributed to the high concentrations of plant toxins present in such a diet. Little empirical work has been conducted examining the mechanisms mammalian herbivores employ to cope with plant toxins. This project will involve the examination of the role toxin absorption plays in intake of toxic plants by mammalian herbivores. The hypothesis that dietary specialists will absorb fewer toxins per unit ingested than generalists will be tested by measuring toxin intake, blood concentration of toxins, and fecal excretion of toxins by specialists (koalas) and generalists (brushtail and mountain brushtail possums) fed the toxic plant, Eucalyptus. It is predicted that lower absorption of toxins by specialists will result in greater toxin intake yet lower concentrations of toxin in the blood. The PI has found evidence within the genus Neotoma that specialists absorb fewer plant toxins than generalists and proposed research will further expand these results by comparing toxin absorption and the mechanisms that mediate toxin absorption between specialist and generalist mammalian herbivores from different families.