ABSTRACT
The gut microbiome reflects health and predicts possible disease in hosts. A holistic view of this community is needed, focusing on identifying species and dissecting how species interact with their host and each other, regardless of whether their presence is beneficial, inconsequential, or detrimental. The distribution of gut-associated eukaryotes within and across non-human primates is likely driven by host behavior and ecology. To ascertain the existence of free-living amoebae (FLA) in the gut of wild and captive non-human primates, 101 stool samples were collected and submitted to culture-dependent microscopy examination and DNA sequencing. Free-living amoebae were detected in 45.4% (46/101) of fecal samples analyzed, and their morphological characteristics matched those of Acanthamoeba spp., Vermamoeba spp., heterolobosean amoeboflagellates and fan-shaped amoebae of the family Vannellidae. Sequence analysis of the PCR products revealed that the suspected amoebae are highly homologous (99% identity and 100% query coverage) with Acanthamoeba T4 genotype and Vermamoeba vermiformis amoebae. The results showed a great diversity of amoebae in the non-human primate's microbiome, which may pose a potential risk to the health of NHPs. To our knowledge, this is the first report of free-living amoebae in non-human primates that are naturally infected. However, it is unknown whether gut-borne amoebae exploit a viable ecological niche or are simply transient residents in the gut.
ABSTRACT
The enteric protist Blastocystis is one of the most frequently reported parasites infecting both humans and many other animal hosts worldwide. A remarkable genetic diversity has been observed in the species, with 17 different subtypes (STs) on a molecular phylogeny based on small subunit RNA genes (SSU rDNA). Nonetheless, information regarding its distribution, diversity and zoonotic potential remains still scarce, especially in groups other than primates. In Brazil, only a few surveys limited to human isolates have so far been conducted on Blastocystis STs. The aim of this study is to determine the occurrence of Blastocystis subtypes in non-human vertebrate and invertebrate animal groups in different areas of the state of Rio de Janeiro, Brazil. A total of 334 stool samples were collected from animals representing 28 different genera. Blastocystis cultivated samples were subtyped using nuclear small subunit ribosomal DNA (SSU rDNA) sequencing. Phylogenetic analyses and BLAST searches revealed six subtypes: ST5 (28.8%), ST2 (21.1%), ST1 and ST8 (19.2%), ST3 (7.7%) and ST4 (3.8%). Our findings indicate a considerable overlap between STs in humans and other animals. This highlights the importance of investigating a range of hosts for Blastocystis to understand the eco-epidemiological aspects of the parasite and its host specificity.
Subject(s)
Blastocystis/classification , Blastocystis/genetics , Animals , Brazil , DNA, Protozoan/genetics , DNA, Ribosomal/genetics , Molecular Epidemiology/methods , PhylogenyABSTRACT
BACKGROUND: Parasites are agents of diarrhea in captive non-human primates (NHP). To broaden information about those etiological agents in captive animals in Brazil, gastrointestinal parasites in captive NHP were researched in nurturing Centers of Rio de Janeiro State. METHODS: Fecal samples were collected from primates, of which 960 came from the Research Center (Cecal/Fiocruz) and 115 from the Primate Center (CPRJ/Inea). The study involved species of the New World (NW) primates and of the Old World (OW). RESULTS: The estimated prevalence was 56.7%, of which 91.3% presented protozoans and 7.4% presented helminths. Statistical difference between the nurturing centers occurred in the overall value of parasitosis and in the isolated frequency of Balantidium coli and Entamoeba sp., especially in the samples of OW primates living in Cecal. CONCLUSIONS: These results demonstrated the need for implements of sanitation programs in the sites for captive primates nurturing.
