RESUMO
Abstract Arthropod-borne pathogens are medically important because of their ability to cause diseases in their hosts. The purpose of this study was to detect the occurrence of Ehrlichia spp., piroplasmids and Hepatozoon spp. in dogs with anemia and thrombocytopenia in southern Brazil. EDTA-whole blood was collected from 75 domestic dogs presenting anemia or/and thrombocytopenia from Guarapuava, state of Paraná, Brazil. DNA samples were subjected to conventional PCR assays for Ehrlichia spp. (dsb), piroplasmids (18S rRNA) and Hepatozoon spp. (18S rRNA), followed by sequencing and phylogenetic analyses. Among the 75 dogs, one (1.33%) was positive for Hepatozoon sp. and six (8%) were positive for piroplasmids in 18S rRNA cPCR assays. None of the dogs showed positive results in Ehrlichia spp.-cPCR targeting dsb gene. The phylogenetic analyses revealed that three piroplasm sequences were clustered with Rangellia vitalii, while one sequence was grouped with B. vogeli. The only sequence obtained from Hepatozoon spp.-PCR protocol was pooled with H. canis. Therefore, there is urgent need for differential molecular diagnosis of the two piroplasm species cited as etiological agents in clinical cases of canine hemoparasitic diseases, given the higher pathogenic potential of R. vitalii than of B. vogeli.
Resumo Agentes transmitidos por artrópodes têm grande importância na medicina veterinária devido à sua capacidade de causar doenças graves em seus hospedeiros. O presente estudo objetivou investigar a ocorrência de três patógenos transmitidos por vetores, Ehrlichia canis, Rangelia vitalii e Hepatozoon canis, em cães na região sul do Brasil. Foram coletadas amostras de sangue total de 75 cães domésticos que apresentavam anemia e/ou trombocitopenia, em Guarapuava, Paraná, Brasil. As amostras de DNA foram submetidas à técnica de PCR convencional para E. canis (dsb), piroplasmídeos (18S rRNA) e Hepatozoon spp. (18S rRNA), seguida de sequenciamento e análises filogenéticas. Das 75 amostras, uma (1,33%) foi positiva para Hepatozoon spp. e seis (8%) foram positivas para Babesia spp. Nenhuma amostra mostrou resultados positivos para Ehrlichia spp. utilizando a detecção pelo gene dsb. As análises filogenéticas revelaram que três sequências obtidas foram agrupadas no mesmo clado que R. vitalii , enquanto uma foi agrupada juntamente com B. vogeli. A única sequência obtida pelo protocolo de PCR para Hepatozoon spp. foi agrupada juntamente com H. canis. Assim, é justificada necessidade de diferenciação das espécies de piroplasmas, através do diagnóstico molecular, como agentes etiológicos nos casos clínicos de hemoparasitose canina, considerando o potencial patogênico de R. vitalii quando comparado à B. vogeli.
Assuntos
Animais , Cães , Infecções Protozoárias em Animais/diagnóstico , Trombocitopenia/veterinária , Ehrlichiose/veterinária , Doenças do Cão/diagnóstico , Anemia/veterinária , Filogenia , Infecções Protozoárias em Animais/microbiologia , Infecções Protozoárias em Animais/parasitologia , Trombocitopenia/diagnóstico , Trombocitopenia/microbiologia , Trombocitopenia/parasitologia , RNA Ribossômico 18S , DNA de Protozoário/genética , Piroplasmida/genética , Eucoccidiida/genética , Ehrlichiose/diagnóstico , Ehrlichia canis/genética , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Anemia/diagnóstico , Anemia/microbiologia , Anemia/parasitologiaRESUMO
The present investigation was carried out to evaluate the validity and accurancy of some laboratory tests in diagnosing early pregnancy in buffaloes as a tool to reduce the breeding and calving intervals. Therefore, plasma progesterone concentration and thrombocyte counts were determined before and after natural service or insemination. Precipitation test, using foetal antibodies and cotyledons antibodies was performed in the plasma of the examined animals [3-5 weeks post-service or insemination]. Results of the present investigation revealed that no early pregnancy associated thrombocytopenia was detected in buffaloes which make this test invalid for detection of early pregnancy. Application of precipitation test using foetal antibodies, although still in a stage of developing, its accuracy was 78.43% in pregnant and 84.75% in non pregnant buffaloes. In addition, the accuracy of precipitation test using cotyledons antibodies was 74% in pregnant and 79.45% in non pregnant buffaloes. Thuse, it can be concluded that the precipitation test using foetal or cotyedons antibodies is simple, paratical, useful and can be used under field conditions