Levantamento sorológico e molecular de patógenos transmitidos por carrapatos em cães do Norte do Brasil

O estudo teve como objetivo avaliar a ocorrência de anticorpos anti-Rickettsia spp. e anti-Ehrlichia canis, bem como a detecção molecular de DNA de Babesia vogeli, Ehrlichia spp. e Hepatozoon spp. em cães do município de Ji-Paraná, estado de Rondônia, norte do Brasil. Para tanto, foram analisadas 177 amostras de soro e sangue por meio reação de imunofluorescência indireta (RIFI) e reação em cadeia pela polimerase (PCR), respectivamente. Um total de 8,47 (15/177) cães foram sororreativos para pelo menos uma espécie de Rickettsia, com títulos finais variando de 64 a 1.024. Os títulos finais mais elevados foram observados para Rickettsia parkeri e Rickettsia rhipicephali. Além disso, anticorpos anti-E. canis foram detectados em 24,29% (43/177) das amostras de soro testadas, com títulos finais variando de 80 a 2.560. Dentre as amostras de sangue analisadas molecularmente, 5,65% (10/177), 22,03% (39/177) e 48,02% (85/177) estavam infectados por B. vogeli, E. canis e Hepatozoon canis, respectivamente. Neste trabalho, fornecemos evidências sorológicas de Rickettsia spp., e E. canis além disso, confirmamos a ocorrência de DNA de B. vogeli, E. canis e H. canis em cães da área rural do estado de Rondônia. região oeste da Amazônia brasileira

Rural area of the Brazilian Pantanal wetlands associated with the occurrence of anti-Leishmania spp. antibodies in dogs

Neste trabalho foi realizada uma avaliação sobre a presença de anticorpos anti-Leishmania infantum chagasi em cães domésticos das áreas urbanas e rurais da região do Pantanal brasileiro usando técnicas sorológicas. Um total de 429 cães foram amostrados em três áreas do bioma do Pantanal, incluindo os municípios de Poconé, Santo Antônio de Leverger e Barão de Melgaço, em Mato Grosso, e o município de Corumbá, em Mato Grosso do Sul. A reação de imunofluorescência indireta (RIFI) foi utilizada para detectar anticorpos (ponto de corte de 40) de Leishmania infantum chagasi como antígeno. Devido à possibilidade de reação cruzada entre as espécies do gênero Leishmania, as amostras positivas na RIFI para L. infantum chagasi foram também avaliadas na RIFI utilizando L. amazonensis e L. braziliensis como antígenos. As amostras positivas na RIFI para L. infantum chagasi foram avaliadas utilizando o ensaio de imunoadsorção ligado à enzima (ELISA). Os resultados mostraram a presença de anticorpos contra L. infantum chagasi em 23 (5,36%; IC 95%: 3,50% -8,05%) cães e pelo menos um cão soro-reativo foi encontrado em todos os municípios avaliados neste estudo. Os títulos de anticorpos variaram de 40 a 5.120 e todas as amostras positivas na RIFI foram positivas no ELISA. Entre os 23 cães positivos, nove também reagiram para L. amazonensis e L. braziliensis. A ocorrência de anticorpos anti-L. infantum chagasi em cães foi maior nas áreas rurais (7,06%) do que nas áreas urbanas (2,50%) (P < 0,05). Com base neste estudo, concluímos que cães de áreas rurais do Pantanal tiveram contato com espécies de Leishmania, o que é uma informação relevante, dada a sua importância para a saúde pública.An evaluation was made of the presence of anti-Leishmania infantum chagasi antibodies in domestic dogs from the urban and rural areas of Brazil’s Pantanal wetland region using serological techniques. A total of 429 dogs were sampled in three areas of the Pantanal biome, including the municipalities of Poconé, Santo Antônio de Leverger, and Barão de Melgaço, in the state of Mato Grosso, and in the municipality of Corumbá, in the state of Mato Grosso do Sul. The immunofluorescence assay (IFA) was used to detect antibodies (cut-off point 40) using Leishmania infantum chagasi antigen. Because of the possibility of cross-reactivity between species of the genus Leishmania, samples that were positive in the IFA against L. infantum chagasi were also tested by IFA in the same conditions, using L. amazonensis and L. braziliensis antigens. IFA-positive samples to L. infantum chagasi were also evaluated using Enzyme-Linked Immunosorbent Assay (ELISA). The results showed the presence of antibodies against L. infantum chagasi in 23 (5.36%; 95% CI: 3.50%-8.05%) dogs and at least one seroreactive dog was found in each of the municipalities evaluated in this study. Antibody titers ranged from 40 to 5,120, and all IFA positive samples were positive in the ELISA. Among the 23 positive dogs, nine were also were seroreactive for L. amazonensis and L. braziliensis antigens. The occurrence of anti- L. infantum chagasi antibodies in dogs was higher in rural areas (7.06%) than in urban areas (2.50%) (P < 0.05). Based on this study, we concluded that dogs from rural areas of the Pantanal wetlands were in contact with Leishmania species, which is relevant information given their importance to public health

Molecular detection of Ehrlichia canisin dogs from the Pantanal of Mato Grosso State, Brazil

The present study evaluated the presence of EhrlichiaDNA in the blood samples of 320 dogs from the urban and rural areas of the municipality of Poconé, Pantanal region, Mato Grosso state, by Polymerase Chain Reaction (PCR), targeting the ehrlichial dsbgene. Risk factors for infection in dogs were also evaluated. Forty-eight (15%, 95% CI: 11.4-19.5%) dogs were positive: 25 (15.6%, 95% CI: 10.4-22.2%) from the urban area and 23 (14.4%, 95% CI: 9.3-20.8%) from the rural area (P > 0.05). Partial DNA sequence obtained from PCR products of 18 samples from the urban area and 16 samples from the rural area were 100% identical to E. canis from Brazil and the USA. This study reports the first E. canis molecular detection in dogs from the northern Pantanal region

Prevalence of canine monocitic ehrlichiosis and canine thrombocytic anaplasmosis in dogs suspected of hemoparasitosis in Cuiabá Mato Grosso

The present study evaluated Canine Monocytic Ehrlichiosis and Canine Thrombocytic Anaplasmosis in 77 dogs treated at the Veterinary Hospital (HOVET) of the Federal University of Mato Grosso (UFMT) in 2009. An association among clinical and hematological, serological and molecular data was investigated. Dogs were evaluated by partial amplification of dsb and 16S rRNA of Ehrlichia canis and Anaplasma platys and by Indirect Fluorescence Antigen Test (IFAT) for E. canis. DNA of E. canis and A. platys were detected in 18 (23.3%) and 07 (9.1%) dogs respectively. Fifty four (70.1%) dogs were positive by IFAT with titers ranging from 40 to 327,680. There were higher frequencies of E. canis positive PCR in dogs less than 12 months old, with anemia, lymphopenia and thrombocytopenia (P?0.05). Leukopenic dogs presented tendency to be A. platys PCR positive (P=0.07). Thrombocytopenia and hyperproteinemia of dogs were associated with high anti-E. canis antibody titers (P?0.05). Lymphadenopathy and pulmonary changes were observed in 15 (30.6%) and 4 (57.1%) E. canis PCR positive dogs (P?0.05). No other clinical features were associated between E. canis and A. platys infected dogs. E. canis was the only specie of Ehrlichia detected in dogs attended at the HOVET with a higher infection rate in young dogs, and statistically associated with anemic and thrombocytopenic dogs. On the other side, A. platys presented low occurrence among evaluated dogs

Detecção molecular de Ehrlichia canis em carrapatos Rhipicephalus sanguineus (s.l.), em cães e em seus ambientes domésticos em Cuiabá, MT, Brasil

The central region of Brazil is known to be an endemic area for canine ehrlichiosis. Therefore, this study aims to determine the prevalence rates of E. canis infection in dogs and in Rhipicephalus sanguineus ticks collected from the dogs and their home environments. Serum samples and genomic DNA from the blood of 20 dogs and 299 ticks were analyzed by IFA and PCR assays in order to detect Ehrlichia canis antibodies and DNA. Nine (45%) of the 20 dogs were seropositive for E. canis, with titers ranging from 80 to 10240, and 6 dogs (30%) were positive for Ehrlichia spp. by PCR. Five free-living ticks were positive (2.89%, 95% confidence interval: 0.94-6.62%), as were six ticks attached to dogs (4.76%; 95% CI: 1.77-10.0%). The two groups showed a similar infection rate (P=0.395). Partial dsb DNA sequences of two samples from ticks were identical to each other and 100% (350/350 nucleotides) were identical to E. canis. Despite the high serological and molecular rates of canine ehrlichiosis in Cuiabá, the prevalence among infected ticks was lower than that found among dogs. However, adult ticks may remain infective much longer to ensure their infestation and infection of susceptible dogs.A região central do Brasil é caracterizada como uma área endêmica para erliquiose canina. Devido a isso, o presente estudo objetivou determinar a prevalência de infecção em cães e seus carrapatos R. sanguineus, coletados a partir do mesmo ambiente. As amostras de soro e DNA genômico de sangue de 20 cães e 299 carrapatos foram testadas por RIFI e PCR a fim de detectar anticorpos e DNA de Ehrlichia canis. Do total, 9 (45%) eram soropositivos para E. canis com títulos variando de 80 a 10240 e 6 cães (30%) positivos para Ehrlichia spp. por PCR. Cinco carrapatos de vida livre (2,89%; intervalo de confiança 95%: 0,94-6,62%), e 6 carrapatos fixados em cães (4,76%; IC 95%: 1,77-10,0%) foram positivos. A taxa de infecção foi semelhante entre ambos os grupos (P=0.395). As sequências parciais do gene dsb de 2 amostras de carrapatos foram idênticas entre si e 100% (350/350) idênticas à E. canis. Apesar das altas taxas sorológicas e moleculares de erliquiose canina em Cuiabá, a prevalência de carrapatos infectados foi menor que o encontrado emcães. Por outro lado, os carrapatos adultos podem permanecer infectados por tempo suficiente para garantir a infestação e infecção aos cães susceptíveis

Genetic diversity and molecular survey of Trypanosoma (Megatrypanum ) theileri in cattle in Brazil’s western Amazon region

Abstract Trypanosoma (Megatrypanum) theileri is a flagellated protozoan that infects ruminants and it displays high genetic diversity. In this study, we investigated the prevalence rates of this protozoan based on hemoculture and molecular diagnosis. The isolates of T. theileri thus obtained were characterized by molecular markers SSU rDNA and gGAPDH and molecular diagnosis based on Cathepsin L-like gene (PCR-TthCATL). The PCR-TthCATL and hemoculture indicated an overall prevalence rate of 8.13%, and the CATL derived sequence named IB was identified for the first time in cattle in the western Amazon region, as well as IF in Brazil. We also describe a possible new PCR-TthCATL derived sequence in cattle, designated IL

Prevalence of 'Candidatus Mycoplasma haemobos' detected by PCR, in dairy cattle from Ji-Paraná in the north region of Brazil

ABSTRACT: The municipality of Ji-Paraná, Rondônia, is one of the major dairy production areas in the north region of Brazil. Thus, it is important to evaluate infectious agents that have the potential to negatively affect productivity in the industry. The objective of this study was to investigate the prevalence of ' Candidatus Mycoplasma haemobos' by using a PCR-based detection method and correlate this with dairy herd variables (abortion frequency, weak calf birth rate, total cattle number, >24-month-old cow number, farm size, and production system) in family farms of the Ji-Paraná municipality, north region, Brazil. Blood samples were collected from 320 dairy cows located across 64 farms (i.e., five animals per farm) from September 2012 to November 2013. Overall prevalence of 'Ca. M. haemobos' was 64.2% and prevalence per herd was 95.3%; the number of >24-month-old cows in the farms studied correlated with ' Ca. M. haemobos' infection rates. Considering the importance of the dairy industry to the study area, additional investigations are necessary to evaluate the effect of chronic infection in these animals on milk production and herd health