2015 年 23 巻 4 号 p. 175-183
Intestinal microbiota play an important role in digestion and host’s health. Furthermore, their composition is complex, with large differences between animal species. Intestinal microbiota have been intensively studied in humans, whereas those in animals, especially in the wild, have not been thoroughly studied. In this study, we focused on the intestinal microbiota of wild western lowland gorillas, chimpanzees, and an elephant in Moukalaba-Doudou National Park in Gabon by using pyrosequencing analysis for understanding their characteristics. Pyrosequencing of their fecal samples yielded 16,898 reads with a read length of 390 nucleotides (10,860,585 nucleotides in total) on average, and taxonomic analysis of metagenomic reads was performed by BLAST search. In almost all animal feces, Prevotellaceae, Clostridiaceae, and Lachnospiraceae were detected as major bacterial families. At the genus level, no-rank Operational Taxonomic Units (OTUs), 80%-90% identities with known sequences, covered a major of fecal microbiota which seemingly determine the enterotype of the host. However, in principal coordinate analysis using weighted UniFrac, their fecal bacteria were clustered by species of host. The result in the present study suggests that it is necessary that no-rank OTUs and minor populations of the fecal bacteria should be analyzed in detail to understand the true characteristics such as functionality of intestinal microbiota.