Prevalence of Trypanosoma lainsoni and its effects of parasitism on the health of non-volant small mammals from the Brazilian Cerrado.

Small mammals are important hosts and/or reservoirs of Trypanosoma spp. This study aimed to verify the prevalence of Trypanosoma spp. in non-volant small mammals from the Brazilian Cerrado and to test the effects of T. lainsoni on the neutrophil/lymphocyte ratio (N/L) and body condition in rodent and marsupial populations. For this, we collected blood samples of 293 individuals captured in five forest fragments between 2019 and 2020. Blood was used to prepare the blood smears and packed on filter paper for DNA extraction. Generalized linear models were performed to test the effects of T. lainsoni on host health. The DNA was submitted to nested PCR targeting the Trypanosoma spp. 18S rRNA gene. From blood smears analyzed by microscopy, we obtained a positivity rate of 7.2% for Trypanosoma spp. About 31.1% of Gracilinanus agilis, Didelphis albiventris, and Rhipidomys macrurus samples were positive in nested PCR. From the obtained sequences, 83.3% were genetically identical to T. lainsoni and about 11% to T. cruzi TcI. In addition, we reported the infection of T. lainsoni in Hylaeamys megacephalus. We suggest that T. lainsoni does not influence the body condition and N/L ratio for either G. agilis or R. macrurus. Overall, our results expand the host list of T. lainsoni and demonstrate the infection of small mammals by T. cruzi TcI in peri-urban areas.

First report of the intestinal helminth community in the broad-headed spiny-rat Clyomys laticeps (Rodentia, Echimyidae).

The broad-headed spiny rat, Clyomys laticeps, is an echimyid rodent found in open areas of Cerrado and Pantanal biomes in central Brazil and Paraguay. Little is known about the parasites associated with this semi-fossorial species, as no previous studies have been conducted on their helminth fauna. The aim of this study was to report the helminth community structure of C. laticeps inhabiting Serra de Caldas Novas State Park, a Cerrado area in central Brazil. Trappings were carried out in dry grasslands from January to October 2016, and the large and small intestines of 14 C. laticeps individuals were examined for the presence of helminths. Three nematode species were found: Fuellebornema almeidai, Pterygodermatites (Paucipectines) sp., and Subulura forcipata, and 85.7% of the studied species were infected with at least one of these helminths. F. almeidai was the most prevalent species among hosts, and S. forcipata was the most abundant. This study is the first report on helminth community structure in C. laticeps. We report a new host species and increase the known geographical range of F. almeidai, and provide the first record of Pterygodermatites (Paucipectines) sp. infecting echimyids. This is also the first report of S. forcipata in a mammal host.

First report of the intestinal helminth community in the broad-headed spiny-rat Clyomys laticeps (Rodentia, Echimyidae) / Primeiro registro da comunidade de helmintos intestinais do rato de espinho Clyomys laticeps (Rodentia, Echymyidae)

Abstract The broad-headed spiny rat, Clyomys laticeps, is an echimyid rodent found in open areas of Cerrado and Pantanal biomes in central Brazil and Paraguay. Little is known about the parasites associated with this semi-fossorial species, as no previous studies have been conducted on their helminth fauna. The aim of this study was to report the helminth community structure of C. laticeps inhabiting Serra de Caldas Novas State Park, a Cerrado area in central Brazil. Trappings were carried out in dry grasslands from January to October 2016, and the large and small intestines of 14 C. laticeps individuals were examined for the presence of helminths. Three nematode species were found: Fuellebornema almeidai, Pterygodermatites (Paucipectines) sp., and Subulura forcipata, and 85.7% of the studied species were infected with at least one of these helminths. F. almeidai was the most prevalent species among hosts, and S. forcipata was the most abundant. This study is the first report on helminth community structure in C. laticeps. We report a new host species and increase the known geographical range of F. almeidai, and provide the first record of Pterygodermatites (Paucipectines) sp. infecting echimyids. This is also the first report of S. forcipata in a mammal host.

Resumo Clyomys laticeps é um roedor equimídeo encontrado em áreas abertas dos biomas Cerrado e Pantanal, ao longo do Brasil central e Paraguai. Essa espécie apresenta hábitos semi-fossoriais e atividade noturna. Até o momento, não existem estudos sobre seus parasitas. O objetivo deste trabalho foi descrever a comunidade de helmintos encontrados em C. laticeps, capturados no Parque Estadual da Serra de Caldas Novas, uma área de Cerrado no Brasil Central. Os indivíduos foram capturados em área de "campo sujo" entre janeiro e outubro de 2016. Os intestinos delgado e grosso de 14 roedores foram examinados quanto à presença de helmintos. Três espécies de nematoides foram encontradas: Fuellebornema almeidai, Pterygodermatites (Paucipectines) sp. e Subulura forcipata. Considerando-se as três espécies, 85,7% dos roedores apresentaram pelo menos um helminto. F. almeidai foi a espécie mais prevalente, enquanto Subulura forcipata foi a mais abundante. Este estudo é o primeiro registro da estrutura da comunidade de helmintos para C. laticeps. Como resultado, foi registrado um novo hospedeiro e o aumento da área de distribuição geográfica para o nematódeo F. almeidai e o primeiro caso de Pterygodermatites (Paucipectines) sp. infectando um roedor equimídeo. Além disso, este estudo também traz o primeiro registro de S. forcipata infectando um mamífero.