Publications (7)8.63 Total impact
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Article: Molecular characterization of Hepatozoon sp. from Brazilian dogs and its phylogenetic relationship with other Hepatozoon spp.
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ABSTRACT: To characterize phylogenetically the species which causes canine hepatozoonosis at two rural areas of Rio de Janeiro State, Brazil, we used universal or Hepatozoon spp. primer sets for the 18S SSU rRNA coding region. DNA extracts were obtained from blood samples of thirteen dogs naturally infected, from four experimentally infected, and from five puppies infected by vertical transmission from a dam, that was experimentally infected. DNA of sporozoites of Hepatozoon americanum was used as positive control. The amplification of DNA extracts from blood of dogs infected with sporozoites of Hepatozoon spp. was observed in the presence of primers to 18S SSU rRNA gene of Hepatozoon spp., whereas DNA of H. americanum sporozoites was amplified in the presence of either universal or Hepatozoon spp.-specific primer sets; the amplified products were approximately 600bp in size. Cloned PCR products obtained from DNA extracts of blood from two dogs experimentally infected with Hepatozoon sp. were sequenced. The consensus sequence, derived from six sequence data sets, were blasted against sequences of 18S SSU rRNA of Hepatozoon spp. available at GenBank and aligned to homologous sequences to perform the phylogenetic analysis. This analysis clearly showed that our sequence clustered, independently of H. americanum sequences, within a group comprising other Hepatozoon canis sequences. Our results confirmed the hypothesis that the agent causing hepatozoonosis in the areas studied in Brazil is H. canis, supporting previous reports that were based on morphological and morphometric analyses.Veterinary Parasitology 05/2007; 145(1-2):21-30. · 2.58 Impact Factor -
Article: Diagnosis of Hepatozoon spp. in Amblyomma ovale and its experimental transmission in domestic dogs in Brazil.
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ABSTRACT: Transmission of Hepatozoon spp. to dogs was investigated using four species of ixodid ticks: Rhipicephalus sanguineus, Amblyomma aureolatum, Amblyomma ovale and Amblyomma cajennense. We collected completely or partially engorged adult ticks of these species from dogs that were naturally infested and positive for Hepatozoon spp. We selected some of these ixodids and inoculated them orally in four negative dogs. The other ticks were dissected and examined for oocysts. Of all dogs inoculated orally with R. sanguineus, A. aureolatum, A. cajennense and A. ovale, only the animal that received the macerate of A. ovale was positive; evidence (gametocytes in peripheral blood) of infection was found 63 days after inoculation. Among all dissected ticks, we found only two oocysts; these were similar to those of Hepatozoon canis, and both were recovered from a single A. ovale specimen. We inoculated sporozoites recovered from the oocysts intraperitoneally into a Hepatozoon spp. negative dog, and circulating gametocytes were detected 84 days later. Our study demonstrated that A. ovale can be a vector of Hepatozoon spp. in Brazil.Veterinary Parasitology 12/2005; 134(1-2):1-7. · 2.58 Impact Factor -
Article: Hepatozoon canis infection associated with dog ticks of rural areas of Rio de Janeiro State, Brazil.
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ABSTRACT: Hepatozoon canis is a tick-borne protozoan that infects dogs and has been reported throughout the world. Manifestation of H. canis infection varies from being sub-clinical in apparently healthy dogs to severe illness. The main vector of the infection is the dog tick, Rhipicephalus sanguineus although other species may also transmit this agent. H. canis has been reported previously in Brazil, but mostly as an occasional finding during laboratory exams and always associated with other diseases. The prevalence of H. canis in dogs of rural areas of Brazil has been little studied. For this study, 250 dogs from seven counties of Rio de Janeiro state were examined. All the dogs were from rural areas, near forest. Of the dogs examined, 26 dogs were from Seropédica, 82 from Itaguaí, 41 from Paracambi, 26 from Mangaratiba, 32 from Barra do Piraí, 32 from Piraí and 11 from Miguel Pereira. Blood smears from the peripheral blood of the ear were taken and ticks found on the dogs were collected for identification in the laboratory. Using blood smear evaluation, H. canis was identified in 39.2% of the animals examined. Other hemoparasites identified were Babesia canis (5.2%) and Ehrlichia canis (4.8%). Four tick species were found parasitizing the dogs: Amblyomma cajennense (23.6%), R. sanguineus (12.4%), Amblyomma aureolatum (2.8%) and Amblyomma ovale (2.0%). There was a positive correlation between the presence of A. cajennense and H. canis infection.Veterinary Parasitology 02/2001; 94(3):143-50. · 2.58 Impact Factor -
Article: [The genus Chorioptes gervais,1895, parasite of ruminants in Brazil (Psoroptidae, Acarina)].
Revista Brasileira de Biologia 01/1977; 36(4):871-2. -
Article: Diagnosis of Hepatozoon spp. in Amblyomma ovale and its experimental transmission in domestic dogs in Brazil
[show abstract] [hide abstract]
ABSTRACT: Transmission of Hepatozoon spp. to dogs was investigated using four species of ixodid ticks: Rhipicephalus sanguineus, Amblyomma aureolatum, Amblyomma ovale and Amblyomma cajennense. We collected completely or partially engorged adult ticks of these species from dogs that were naturally infested and positive for Hepatozoon spp. We selected some of these ixodids and inoculated them orally in four negative dogs. The other ticks were dissected and examined for oocysts. Of all dogs inoculated orally with R. sanguineus, A. aureolatum, A. cajennense and A. ovale, only the animal that received the macerate of A. ovale was positive; evidence (gametocytes in peripheral blood) of infection was found 63 days after inoculation. Among all dissected ticks, we found only two oocysts; these were similar to those of Hepatozoon canis, and both were recovered from a single A. ovale specimen. We inoculated sporozoites recovered from the oocysts intraperitoneally into a Hepatozoon spp. negative dog, and circulating gametocytes were detected 84 days later. Our study demonstrated that A. ovale can be a vector of Hepatozoon spp. in Brazil.Veterinary Parasitology. -
Article: [Epidemiological aspects of canine American tegumentary leishmaniasis in the Municipality of Paraty, State of Rio de Janeiro, brazil].
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ABSTRACT: American tegumentary leishmaniasis (ATL) is endemic in the State of Rio de Janeiro, with the highest incidence observed in the municipalities along the Southern coast. A total of 169 human cases were reported from 1993 to 1995 in the municipality of Paraty, representing 15% of all case reports in the State of Rio de Janeiro during that period. From March to December, 1996, a survey was conducted in endemic american tegumentary leishmaniasis (ATL) areas (Praia Grande, Taquari, Várzea do Machado, and Graúna) in Paraty. 326 households with 215 pet dogs were surveyed. The initial study consisted of taking venous blood samples to perform RIFI and ELISA tests. The canine skin test was performed during the same visit and was positive in 8.8% of dogs. Of the 215 dogs, 5 presented lesions suspected of ATL; biopsies and the vacuum aspiration technique were performed on these cases. Correlating the study areas with the results obtained, some dogs presented sub-clinical infection, highly relevant to studies on canine ATL infection in the State of Rio de Janeiro.Cadernos de Saúde Pública 15(3):641-6. · 0.89 Impact Factor -
Article: Molecular characterization of Hepatozoon sp. from Brazilian dogs and its phylogenetic relationship with other Hepatozoon spp.
[show abstract] [hide abstract]
ABSTRACT: To characterize phylogenetically the species which causes canine hepatozoonosis at two rural areas of Rio de Janeiro State, Brazil, we used universal or Hepatozoon spp. primer sets for the 18S SSU rRNA coding region. DNA extracts were obtained from blood samples of thirteen dogs naturally infected, from four experimentally infected, and from five puppies infected by vertical transmission from a dam, that was experimentally infected. DNA of sporozoites of Hepatozoon americanum was used as positive control. The amplification of DNA extracts from blood of dogs infected with sporozoites of Hepatozoon spp. was observed in the presence of primers to 18S SSU rRNA gene of Hepatozoon spp., whereas DNA of H. americanum sporozoites was amplified in the presence of either universal or Hepatozoon spp.-specific primer sets; the amplified products were approximately 600 bp in size. Cloned PCR products obtained from DNA extracts of blood from two dogs experimentally infected with Hepatozoon sp. were sequenced. The consensus sequence, derived from six sequence data sets, were blasted against sequences of 18S SSU rRNA of Hepatozoon spp. available at GenBank and aligned to homologous sequences to perform the phylogenetic analysis. This analysis clearly showed that our sequence clustered, independently of H. americanum sequences, within a group comprising other Hepatozoon canis sequences. Our results confirmed the hypothesis that the agent causing hepatozoonosis in the areas studied in Brazil is H. canis, supporting previous reports that were based on morphological and morphometric analyses.Veterinary Parasitology.
Top Journals
Institutions
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2007
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Universidad Centro Occidental Lisandro Alvarado, UCLA
Barquisimeto, Estado Lara, Venezuela
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2005–2007
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Universidade Federal Rural do Rio de Janeiro (UFRRJ)
- Departamento de Parasitologia Animal (DPA)
Rio de Janeiro, Rio de Janeiro, Brazil
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