Cytauxzoon felis and 'Candidatus Mycoplasma haemominutum' coinfection in a Brazilian domestic cat (Felis catus) AbstractThis article describes the first detection of Cytauxzoon felis, using molecular techniques, in a naturally infected domestic cat from Brazil, South America. Coinfection with 'Candidatus Mycoplasma haemominutum' was also found. The molecular identification of the piroplasmid species was performed by Polymerase Chain Reaction (PCR) and sequencing analysis. A 284 pb fragment of the gene encoding the 18S ribosomal RNA region was amplified and showed 99% identity with other C. felis strains from North America. In addition, PCR-RFLP (restriction fragment length polymorphism) analysis, which amplifies a 595 bp fragment of the gene encoding 16S ribosomal RNA of some bacterial species, identified the co-infecting species as 'Candidatus M. haemominutum'.

The aim of this study was to characterize Ehrlichia canis strains from naturally infected dogs in Rio de Janeiro, Brazil. In addition, all the clinical and hematological findings observed in these dogs were reported. PCR targeting the 16S rRNA gene was used for diagnostic purposes, and the TRP19 and TRP36 genes were sequenced to evaluate the genetic diversity. Fifteen samples were positive for E. canis. The polymerase chain reaction for the TRP19 gene resulted in 11 amplicons (11/15), which were cloned into the pGEM-T easy vector for sequencing. The complete sequence of TRP19 gene was compared to those in the GenBank, revealing high identicalness. Phylogenetic analysis on the TRP36 gene sequences demonstrated two distinct strains from two dogs, named 56C and 70C. The 56C strain was grouped with the strain Cuiaba 16, which is a hybrid strain formed by Brazilian and US genogroups; and the 70C strain was grouped with other strains of the US genogroup, thus suggesting that there are at least two genogroups of E. canis in Rio de Janeiro (US and Brazilian). Those animals, in which the 70C and 56C strains were isolated, showed distinct clinical and hematological manifestations of 1the disease. The appearance of different genotypes may express new phenotypes, thus resulting in different forms of presentation of the disease and making its diagnosis more complex.

Hepatozoon canis tem sido descrito em cães de várias regiões do Brasil sendo mais relatado em áreas rurais. O objetivo deste trabalho foi determinar a ocorrência de infecção por Hepatozoon spp. através da reação em cadeia da polimerase (PCR), em cães de região periurbana da cidade de Piraí, RJ. Em setembro/2006, foram coletadas amostras de sangue de 88 cães da cidade, situada no vale do rio Paraíba do Sul. A PCR foi utilizada para a detecção de Hepatozoon spp. (gene 18SRNAr) através de um par de iniciadores gênero-específicos. Duas amostras apresentaram resultado PCR-positivo (2,2%), havendo concordância com a avaliação morfológica em esfregaços sanguíneos. A amostra de Piraí demonstrou alta similaridade (99%) com Hepatozoon canis. Os cães de Piraí apresentaram baixa frequência de infecção por H. canis, quando comparados a pesquisas anteriores na mesma região.

Introduction: Bartonella infection in cats can represent a risk to owners, particularly today when considering the increase in cat populations and their role in human bartonellosis epidemiology. In the present study, we aimed to detect Bartonella spp. in blood samples from 163 asymptomatic privately-owned cats from the metropolitan area of Rio de Janeiro State, Brazil by using a conventional PCR test and also to evaluate the association between Bartonella spp. and hematological changes in positive cats. Methodology: PCR assays were performed targeting the Bartonella spp heat shock protein (htrA) gene and complete blood counts were also performed in all samples. Positive PCR samples were confirmed by the presence of two genes, citrate synthase (gltA) and RNA polymerase beta-subunit-encoding (rpoB). Results: A total of 74.85% (122/163) of the tested cats were positive for Bartonella spp and partial sequencing confirmed to be B. henselae. All hematological findings from the 163 cats tested (PCR-positive and negative), presented normal limits. Conclusions: This study demonstrates that B. henselae is present in almost 75% asymptomatic privately-owned domestic cats in the metropolitan region of Rio de Janeiro State, Brazil. Our results also show that hematological findings in Bartonella spp. infected cats are uncommon. In this scenario, the use of PCR as a diagnostic tool in feline Bartonella infections should be considered. Finally, these results also demonstrate the potential risk of Bartonella spp. infection in the human population of the metropolitan area of Rio de Janeiro State, Brazil.

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