Dados do Trabalho

Título

RICHNESS OF KINETOPLASTIDS INFECTING SMALL MAMMALS FROM PANTANAL REGION

Objetivo(s)

Our aim was to evaluate the richness of kinetoplastids that infect small mammals in the Pantanal by Next Generation Sequencing (NGS) on Illumina HiSeq2500.

Material e Métodos

The study was carried out in a private area located in the central of the Brazilian Pantanal. Small mammals (Rodentia and Didelphimorphia) were captured in February 2021 using 204 Sherman and 204 Tomahawk traps. Traps were placed on the ground for five nights (capture effort of 2040 trap-nights), baited with a mixture of banana, peanut butter, and oats. The collected individuals were anesthetized, and blood was collected via heart puncture. For molecular detection of kinetoplastids we used nested polymerase chain reaction (nPCR) with primers directed to the 18S rDNA gene.

Resultados e Conclusão

We grouped the positive blood samples into pools for each small mammal species: Monodelphis domestica, Thylamys macrurus, Oecomys mamorae, Thrichomys fosteri, Clyomys laticeps, and Holochilus chacaris. The NGS-generated data were analyzed using DADA2 (v1.14.0) in the R environment. Further, taxonomy of kinetoplastids were assigned using SILVA v132 and the blood pools of six species were positive. Amplicon Sequence Variants were assigned for eight parasite species: Leishmania amazonensis; L. infantum; Trypanosoma cascavelli, T. cruzi (DTUS TcI and TCII), T. lainsoni, T. rangeli (lineages A, B and E), Trypanosoma Did, and Neobodo sp. With exception of T. cascavelli (detected only M. domestica), all species of kinetoplastids were found in O. mamorae, being Neobodo spp and T. lainsoni detected only in this species. Leishmania infantum was detected in the blood pools of all species, while L. amasonensis were found in O. mamorae, T. fosteri and C. laticeps; and this represents the first report of Leishmania infection in small mammals from this region. The study of small mammals is of fundamental importance in improving the understanding of trypanosomatid ecology, once they are found both on the ground and in the understory and may favor spill-over of protozoan flagellates among the strata of the natural environment, as O. mamorae. The use of a tool as sensitive as NGS has increased our awareness of the diversity of kinetoplastids as well as their host range. These findings make it mandatory to rethink the kinetoplastids/host associations proposed so far.

Palavras-chave

Keywords: Rodentia, Didelphimorphia, Kinetoplastea, NGS, 18SrDNA