Meeting Abstract
At every meal, herbivorous mammals are confronted with the prospect of being poisoned by the naturally occurring toxins in plants. More than 40 years ago, Freeland and Janzen hypothesized that gut microbes play a key role in facilitating the ingestion of dietary toxins by herbivorous mammals. Early investigations of this hypothesis were limited by experimental techniques and the inability to culture many microbes under laboratory conditions. However, the advent of high-throughput sequencing and metabolomics have enabled rigorous and experimental tests of this hypothesis. Using these approaches, we tested the hypothesis that gut microbes facilitate ingestion of natural dietary toxins by herbivorous woodrats (genus, Neotoma). We have discovered that woodrats harbor a dense, diverse and active community of microbes in their foregut. Moreover, a functioning and diverse gut microbial community plays a critical role in the host’s ability to ingest a toxic diet. We have been able to transfer the gut microbial community of woodrats within and across species lines, thereby improving their ability to ingest toxic diets. The results support the hypothesis that microbes enhance the ability of herbivores to ingest toxic diets and may rapidly permit the host to expand diet breadth without host evolutionary changes. In addition, this basic science holds promising applications for improving human health and enhancing animal husbandry through the development of novel probiotic mixtures.
