Description of the intestinal eukaryote community using the V4 region of the 18s from wild western lowland gorilla. Assessing temporal stability; effect of age, social status, skin disease, location and season on eukaryote community structure.
Investigating the diversity of the intestinal eukaryote community (eukaryome), the relationships between eukaryotes, the factors shaping this community, and its temporal dynamic, are critical steps toward understanding the role the eukaryome plays in health and disease. Here, we used 92 fecal samples from male western lowland gorillas collected from 2000 to 2015 in the Odzala-Kokoua National Park, Republic of Congo. We characterized the diversity of intestinal eukaryotes using the V4 region of the 18s rRNA gene and constructed phylogenetic trees for taxonomic assignment. We found 6 of the main intestinal eukaryotes groups with the following prevalences:  99% for Nematoda, 95% for Blastocystis, 93% for Parabasalia, 92% for Litostomatea, 25% for Entamoebida and 35% for Fornicata. Among these groups, we detected 57 eukaryote lineages, including 21 unreported lineages. In average, gorillas were colonized by 10 lineages but most communities were dominated by Ancylostoma, Oesophagostumum, Cycploposthium, Tetratrichomonas and Blastocystis. We did not find co-exclusion or co-association between lineages, but we found 15 positive correlations between lineages abundance, and the presence of 3 lineages was associated with increase in the eukaryote diversity and richness. This suggest that eukaryotes may mainly promote each other's colonization, or share similar niches. The eukaryote community composition was not impacted by geographic location, age, seasonality, social status, and the presence of yaw. We found that the eukaryote richness was slightly impacted by the geographic location, seasonality and was higher in older gorillas. Few taxa were enriched in some geographic sites and gorillas living in group, suggesting that social structure could promote transmission. Thirteen intestinal eukaryotes were present in individual gorillas over a period of 3 years, suggesting that these taxa can establish long term colonization with their host.