RESUMEN
Reliable data on distributional ranges of soft ticks (Argasidae) and assessments of putative tick-borne agents enhance the understanding on tick-associated microorganisms. A total of 96 ticks morphologicaly and molecularly identified as Ornithodoros rietcorreai were collected in Tocantins State, Brazil, using Noireau traps with living bait as CO2 source. Ninety-six ticks (54 nymphs, 32 males, 10 females) with different engorgement degrees were collected. Fourty-seven (48.9%) of them were individually screened by PCR for detecting bacteria of Anaplasmataceae family and genera Rickettsia, and Borrelia. The presence of protozoans of the genus Babesia was assessed as well. Fourty seven ticks were submitted to analysis. Nine ticks (19.1%) yielded sequences for gltA and htrA genes most identical with a series of endosymbiont rickettsiae and Rickettsia bellii, respectively. Upon two ticks (4.2%) we retrieved DNA of a potential new Wolbachia sp., and DNA of a putative novel Hepatozoon was characterized from three (6.4%) specimens. No DNA of Babesia or Borrelia was detected. Remarkably, amplicons of unidentified eukaryotic organisms, most closely related with apicomplexans but also with dinoflagellates (91% of identity after BLAST analyses), were recovered from two ticks (4.2%) using primers designed for Babesia 18S rRNA gene. Our records expand the distribution of O. rietcorreai into Brazilian Cerrado biome and introduce the occurrence of microorganisms in this tick species.
Asunto(s)
Bacterias/genética , Ornithodoros/microbiología , Ornithodoros/parasitología , Filogenia , Anaplasmataceae/genética , Anaplasmataceae/aislamiento & purificación , Animales , Babesia/genética , Babesia/aislamiento & purificación , Bacterias/aislamiento & purificación , Borrelia/genética , Borrelia/aislamiento & purificación , Brasil , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , ADN Protozoario/genética , ADN Protozoario/aislamiento & purificación , Femenino , Geografía , Larva/microbiología , Masculino , Ninfa/microbiología , Rickettsia/genética , Rickettsia/aislamiento & purificaciónRESUMEN
Taking into account the diversity of small terrestrial mammals of the Pantanal, the present study aimed to verify the occurrence of infection by Ehrlichia spp., Anaplasma spp., Rickettsia spp., Hepatozoon spp., Babesia spp. and parasitism by ticks in non-volant small mammals collected in the Brazilian Pantanal. Samples of blood, liver and spleen were collected from 64 captured animals, 22 marsupials and 42 rodents. Pathogen detection was performed by the use of genus-specific Polymerase Chain Reaction (PCR) assays. Ticks collected from the animals consisted of Amblyomma sculptum and Amblyomma triste nymphs, and Ornithodoros guaporensis larvae. None of the vertebrate samples (blood, liver, or spleen) yielded detectable DNA of Rickettsia spp. or Ehrlichia spp. The blood of the rodent Hylaeamys megacephalus yielded an Anaplasma sp. genotype (partial 16S rRNA gene) 99% similar to multiple Anaplasma spp. genotypes around the world. The blood of three rodents of the species Calomys callosus were positive for a novel Hepatozoon sp. agent, phylogenetically related (18S rDNA gene) to distinct Hepatozoon genotypes that have been detected in rodents from different parts of the world. One marsupial (Monodelphis domestica) and three rodents (Thrichomys pachyurus) were positive to novel piroplasmid genotypes, phylogenetically (18S rDNA gene) related to Theileria bicornis, Cytauxzoon manul, and Cytauxzoon felis. The present study provides the first molecular detection of Hepatozoon sp. and piroplasmids in small mammals in Brazil. Additionally, we expanded the distribution of O. guaporensis to Brazil, since this tick species was previously known to occur only in Bolivia.
Asunto(s)
Anaplasmosis/epidemiología , Babesiosis/epidemiología , Coccidiosis/epidemiología , Filogenia , Theileriosis/epidemiología , Infestaciones por Garrapatas/veterinaria , Enfermedades por Picaduras de Garrapatas/veterinaria , Anaplasma/clasificación , Anaplasma/genética , Anaplasma/aislamiento & purificación , Anaplasmosis/microbiología , Animales , Babesia/clasificación , Babesia/genética , Babesia/aislamiento & purificación , Babesiosis/parasitología , Brasil/epidemiología , Coccidios/clasificación , Coccidios/genética , Coccidios/aislamiento & purificación , Coccidiosis/parasitología , ADN Mitocondrial/genética , Monitoreo Epidemiológico , Femenino , Humanos , Masculino , Marsupiales/microbiología , Marsupiales/parasitología , Ornithodoros/genética , Ornithodoros/microbiología , Ornithodoros/parasitología , ARN Ribosómico 18S/genética , Roedores/microbiología , Roedores/parasitología , Theileria/clasificación , Theileria/genética , Theileria/aislamiento & purificación , Theileriosis/parasitología , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/parasitologíaRESUMEN
Ornithodoros brasiliensis Aragão é um carrapato endêmico do Brasil, restrito às regiões serranas e frias do estado do Rio Grande do Sul. [...] O presente trabalho teve por objetivos estudar a morfologia e a biologia de O. brasiliensis, em condições de laboratório, bem como investigar a presença de bactérias do gênero Rickettsia em espécimes coletados. Ninfas e adultos foram alimentados em cobaias de laboratório e as fêmeas acasaladas realizaram posturas que resultaram nas gerações sucessivas. A larva e os adultos foram descritos e redescritos, e comparados com as espécies próximas, O. rostratus e O. turicata. Análises moleculares de uma porção do gene 16S rDNA mitocondrial foram comparadas com as sequências depositadas no GenBank e apresentaram valores de máximo bootstrap de 100% para ambas, O. rostratus e O. turicata. [...] O primeiro ciclo gonotrófico apresentou maior número de ovos depositados, com 139 ± 13,8 (53 197) em relação ao segundo 73,8 ± 10,6 (53 123). A investigação da presença de riquétsia foi avaliada em 107 espécimes recentemente coletados, evidenciando um total de 12 exemplares positivos. O produto amplificado pela PCR foi sequenciado e as análises moleculares apresentaram homologia de 98% com sequências disponibilizadas no Genbank, correspondentes a uma espécie asiática denominada RDa420 (AF497584) e outra brasileira, Rickettsia bellii (DQ865204)
Ornithodoros brasiliensis Aragão is an endemic tick to Brazil, restricted to the highlands and cold regions of the state of Rio Grande do Sul. [..] This work aimed to study the morphology and biology of O. brasiliensis, under laboratory conditions, and investigate the presence of bacteria of the genus Rickettsia in the collected ticks. Nymphs and adults were fed on laboratory guinea pigs, and mated females laid eggs that resulted in the successive generations. The larvae and adults have been described and redescribed, respectively, and compared with the closely related species, O. rostratus and O. turicata. [...] The first gonotrophic cycle presented higher average number of eggs deposited 139 ± 13,8 (53-197) that the second 73,8 ± 10,6 (53 123). The investigation to the presence of rickettsia was performed in 109 recently collected ticks, showing a total of 12 positive specimens. The amplified PCR product was sequenced and molecular analyzes showed 98% homology with sequences available in Genbank, corresponding to an Asian species named RDa420 (AF497584) e another Brazilian strain named Rickettsia bellii (DQ865204)