Experimental infection by Trypanosoma vivax in goats in the Brazilian semiarid: detection of T. vivax DNA in colostrum and assessment of lactogenic transmission / Infecção experimental por Trypanosoma vivax em caprinos no semiárido brasileiro: detecção de DNA de Trypanosoma vivax no colostro e avaliação da transmissão lactogênica

This study aimed to identify the presence of Trypanosoma vivax DNA in the colostrum of infected goats and to explore the possibility of transmission for neonates fed using colostrum collected from infected goats. We used twelve goats in the final third of gestation with an age of approximately 24 months. Six goats were inoculated intravenously with 0.5mL of blood containing approximately 1.25x105 trypomastigotes of T. vivax, and six remained uninfected. The presence of T. vivax in colostrum was evaluated by Polymerase Chain Reaction (PCR). The possibility of T. vivax transmission by colostrum was assessed by feeding six neonates born of serologically negative goats using colostrum from infected goats. Peripheral blood from neonates was collected daily for thirty days to assess the T. vivax presence through the examination of Giemsa-stained smears of leukocyte layers with the buffy coat technique (BCT) and by PCR. The results of a direct examination of colostrum were negative, but PCR confirmed the presence of T. vivax DNA in all infected goats. Additionally, lactogenic transmission by colostrum was not demonstrated once both BCT and PCR of neonate peripheral blood were negative.

Este estudo teve como objetivo identificar a presença de DNA de Trypanosoma vivax no colostro de cabras infectadas experimentalmente e verificar a possibilidade de transmissão para neonatos alimentados com colostro coletado de cabras infectadas. Foram utilizadas doze cabras no terço final de gestação com idade aproximada de 24 meses. Seis cabras foram inoculadas intravenosamente com 0,5mL de sangue contendo aproximadamente 1,25x105 tripomastigotas de T. vivax, e seis permaneceram não infectadas. A presença de T. vivax no colostro foi avaliada por Reação em Cadeia da Polimerase (PCR). A possibilidade de transmissão de T. vivax pelo colostro foi avaliada através da alimentação de seis neonatos nascidos de cabras sorologicamente negativas com colostro de cabras infectadas. Foi coletado diariamente o sangue periférico dos neonatos, por trinta dias para avaliar a presença de T. vivax através do exame de esfregaços de camadas leucocitárias coradas por giemsa, pela técnica BCT e por PCR. Os resultados do exame direto do colostro foram negativos, mas a PCR confirmou a presença de DNA de T. vivax no colostro em todas as cabras infectadas. Além disso, a transmissão lactogênica pelo colostro não foi demonstrada, uma vez que tanto a BCT quanto a PCR do sangue periférico do neonato foram negativas.

Natural infection of Trypanosoma sp. in domestic sheep from Ecuador / Infecção natural do Trypanosoma sp. em ovelhas domésticas do Equador

Trypanosomosis in sheep is a hemoparasitic disease of worldwide interest due to its effects on the health of animals and the economic impact on producers, is caused by the protozoan Trypanosoma sp. In the present study, the occurrence of Trypanosoma sp. in sheep from the urban-rural area of the canton Salitre was determined, through an applied study with a qualitative descriptive prospective cross-sectional approach, carried out between October 1, 2019, and February 19, 2020. Blood samples were extracted from the jugular vein and analyzed by the blood smear method using the Giemsa and Diff-Quick staining techniques. Previously, in a first study realized between 2018 and 2019, 2 cases (2%) of Trypanosoma sp., 1 case of Babesia sp. (1%), and 4 cases of Anaplasma marginale (4%) were identified, but without the presence of symptoms of the disease. However, in this new research study, of 170 animals sampled from 5 herds and aged between 3 and 8 years, 34 (20%) were positive for Trypanosoma sp., 6 for Babesia sp. (3.52%) and 6 for A. marginale (3.52%) with coinfection between them. In this research, deteriorated clinical aspects and low hematological values were also determined in positive animals; besides of the total of positive cases, 25 presented symptoms of hemoparasitic disease, 3 sheep had abortions and 8 died. The results of this study showed that Trypanosoma sp. could already become an endemic parasitosis in sheep in the country, representing a serious problem of animal health.

A tripanossomose em ovinos é uma doença hemoparasitária de interesse mundial devido a seus efeitos sobre a saúde dos animais e o impacto econômico sobre os produtores, Esta doença é causada pelo protozoário Trypanosoma sp. No presente estudo, foi determinada a ocorrência de Trypanosoma sp. em ovelhas da área urbano-rural do Cantão Salitre, através de um estudo aplicado com uma abordagem transversal descritiva qualitativa prospectiva, realizado entre dia primeiro de outubro de 2019, à 19 de fevereiro de 2020. Amostras de sangue foram extraídas da veia jugular e analisadas pelo método de esfregaço de sangue usando as técnicas de coloração Giemsa e Diff-Quick. Anteriormente, em um primeiro estudo realizado entre 2018 e 2019, dois casos (2%) de Trypanosoma sp., foram identificados um caso de Babesia sp. (1%), e quatro casos de Anaplasma marginale (4%), mas sem a presença de sintomas da doença. Entretanto, neste novo estudo de pesquisa, de 170 animais amostrados de cinco rebanhos e com idades entre três e oito anos, 34 (20%) foram positivos para Trypanosoma sp., seis para Babesia sp. (3,52%) e seis para A. marginale (3,52%) com coinfecção entre eles. Nesta pesquisa, aspectos clínicos deteriorados e baixos valores hematológicos também foram determinados em animais positivos; além do total de casos positivos, 25 apresentaram sintomas de doença hemoparasítica, três ovelhas tiveram abortos e oito morreram. Os resultados deste estudo mostram que o Trypanosoma sp. já poderia se tornar uma parasitose endêmica em ovinos no país, representando um grave problema de saúde animal.

Follow-up of dairy cattle naturally infected by Trypanosoma vivax after treatment with isometamidium chloride / Acompanhamento de bovinos leiteiros naturalmente infectados com Trypanosoma vivax após tratamento com cloreto de isometamidium

Trypanosoma vivax infections cause nonspecific clinical signs in cattle associated with aparasitemic intervals, making disease diagnosis a challenge. In Brazil, diminazene aceturate and isometamidium chloride (ISM) are available to treat bovine trypanosomosis. The objective of this study was to follow-up, by molecular and serological techniques, dairy cattle naturally infected by T. vivax after ISM treatment. Thirty cattle naturally infected with T. vivax received two applications of ISM, at a dosage of 1.0 mg/kg intramuscularly, on days 0 and 150. For T. vivax diagnosis, EDTA-blood and serum samples were evaluated on 0, 7, 15, 30, 60, 90, 120, 150, 180, 210, and 240 days after treatment PCR, Loop-mediated isothermal amplification (LAMP) and ELISA. Animals with persistent detection of T. vivax DNA by both PCR and LAMP were found and continuous detection of anti-T. vivax IgG antibodies by ELISA, suggesting the presence of T. vivax resistance to ISM. The combination of LAMP and ELISA tests can prevent misdiagnosis of the parasite clearance in treated cattle, contributing to better disease control. This is the first experiment that demonstrates the persistence infection of T. vivax under ISM treatment in a natural infected herd and evidence of ISM chemotherapy-resistant T. vivax in Brazil.(AU)

Em bovinos, infecções por Trypanosoma vivax geram sinais clínicos inespecíficos que, associados a intervalos aparasitêmicos, faz com que o diagnóstico da enfermidade seja desafiador. No Brasil, somente aceturato de diaminazeno e cloridrato de isometamidum (ISM) estão disponíveis para o tratamento da tripanossomose bovina. Este trabalho teve como objetivo acompanhar bovinos leiteiros naturalmente infectados por T. vivax, após o tratamento com ISM por meio de técnicas moleculares e sorológica. Foram utilizados 30 bovinos naturalmente infectados com T. vivax, sendo estes tratados com duas aplicações de ISM, na dosagem de 1,0 mg/kg por via intramuscular profunda, nos dias 0 e 150. Foram avaliadas, para diagnóstico de T. vivax, amostras de sangue acrescido de EDTA e soro, colhidas nos 0, 7, 15, 30, 60, 90, 120, 150, 180, 210 e 240 dias após os tratamentos pela reação em cadeia da polimerase (PCR), amplificação circular isotérmica do DNA (LAMP) e ensaio de imunoabsorção enzimático (ELISA). Verificou-se a presença de animais com persistência na detecção de DNA de T. vivax pela PCR e LAMP, bem como detecção contínua de anticorpos IgG anti-T. vivax pelo método de ELISA, sugerindo a presença de resistência de T. vivax ao ISM. A combinação dos testes LAMP e ELISA pode evitar falsos diagnósticos da eliminação do parasita nos bovinos tratados, contribuindo para um melhor controle da doença. Este é o primeiro experimento que demonstra infecção persistente do T. vivax em rebanho naturalmente infectado, tratado com ISM, e evidencia possível resistência ao quimioterápico no Brasil.(AU)

Comparison of conventional and molecular techniques for Trypanosoma vivax diagnosis in experimentally infected cattle / Comparação de técnicas convencionais e moleculares para diagnóstico em bovinos experimentalmente infectados por Trypanosoma vivax

Livestock infections by Trypanosoma vivax have been occurring with increasing frequency, mainly due to the presence of animals with subclinical infections and without apparent parasitaemia, making diagnosis challenging. The aim of the present study was to evaluate several techniques used for T. vivax diagnosis in order to assess the best way of using them during the course of the disease. Molecular methods demonstrated higher rates of detection than parasitological methods, detecting 33 of the 54 (61.1%) known positive samples, while the hematocrit centrifugation technique (best parasitological test) detected only 44.4%. The serological methods, IFAT and ELISA, detected seropositivity in 51 of the 54 (94.4%) and 49 of the 54 (90.7%) known positive samples, respectively. Despite being highly sensitive, the latter only demonstrates exposure to the infectious agent and does not indicate whether the infection is active. The present study was the first to use the qPCR for a South American isolate, improving disease detection and quantification. Furthermore, the analyses revealed that the patent phase of the disease may extend up to 42 days, longer than previously reported. The combination of several diagnostic techniques can lower the frequency of false negative results and contributes toward better disease control.(AU)

Infecções por Trypanosoma vivax têm ocorrido com frequência crescente em animais de produção, principalmente pela aquisição de animais com infecções subclínicas e sem aparente parasitemia, o que dificulta o diagnóstico. O objetivo do presente estudo foi avaliar várias técnicas empregadas para o diagnóstico de T. vivax, a fim de verificar a melhor maneira de utilizá-las durante o curso da doença. Os métodos moleculares demonstraram maiores taxas de detecção que os métodos parasitológicos, detectando 33 das 54 (61,1%) amostras sabidamente positivas, enquanto a técnica de hemoconcentração (melhor teste parasitológico) detectou apenas 44,4%. Os métodos sorológicos, RIFI e ELISA, detectaram soropositividade em 51 das 54 (94,4%) e 49 das 54 (90,7%) amostras sabidamente positivas, respectivamente. Apesar de serem altamente sensíveis, estes testes apenas demonstram a exposição ao agente infeccioso, e não indicam se a infecção permanece ativa. O presente estudo foi o primeiro a utilizar a qPCR para um isolado sul-americano, melhorando sua detecção e quantificação. Além disso, as análises revelaram que a fase patente da doença pode se estender por até 42 dias após a infecção, sendo maior que anteriormente relatado. A combinação de várias técnicas de diagnóstico pode evitar a frequência de resultados falso-negativos e contribuir para um melhor controle da doença.(AU)

Risk factors for trypanosomiasis by Trypanosoma vivax in cattle raised in Rio Grande do Norte state / Fatores de risco para tripanossomose por Trypanosoma vivax em bovinos criados no estado do Rio Grande do Norte

The objective of this study was to determine the prevalence of anti Trypanosoma vivax antibodies and the possible risk factors associated with the infection in cattle in Rio Grande do Norte, Northeastern Brazil, through a cross-sectional epidemiological study, with non-probabilistic convenience sampling. A total of 467 cattle's serum samples were analyzed by indirect immunofluorescence. Forty-two samples tested positive for Trypanosoma vivax IgG antibodies, corresponding to the prevalence of 9%. Risk factors influencing the occurrence of trypanosomiasis were milk exploration, raising of European breeds, productivity category: lactation cow, purchase of new cattle, foraging habits near ponds and rivers, and the presence of mechanical vectors. So, high prevalence in beef animals (59.5%), females (95.2%), European breed (88.1%), lactating cows (85.7%), pasture at banks of dams and rivers (95.2%), in addition to the presence of mechanical vectors (81%) and acquisition of animals (88.1%), indicates the expansion of trypanosomiasis in Northeastern semi-arid region, and the information obtained may explain the epidemiological factors that determine the occurrence of trypanosomiasis by T. vivax in this region.(AU)

Objetivando determinar a prevalência de anticorpos anti-Trypanosoma vivax e os possíveis fatores de risco associados à infecção em bovinos no estado do Rio Grande do Norte, nordeste do Brasil, o trabalho consistiu em um estudo epidemiológico transversal, com amostragem não probabilística por conveniência, no qual foram analisadas, por meio da reação de imunofluorescência indireta, 467 amostras de soro sanguíneo de bovinos. Das amostras testadas, 42 foram reagentes para anticorpos IgG anti-Trypanosoma vivax, o que correspondeu à prevalência de 9,0%. Os fatores de risco que influenciaram a ocorrência da tripanossomose foram: exploração com finalidade do tipo leite, criação de bovinos de raça europeia, categoria animal vaca em lactação, aquisição de animais, forrageamento das margens de açudes e rios, além da presença de vetores mecânicos. A alta prevalência encontrada em animais de corte (59,5%), fêmeas (95,2%), raça europeia (88,1%), vacas em lactação (85,7%), pastagem a margens de açudes e rios (95,2%), além da presença de vetores mecânicos (81%) e aquisição de animais (88,1%), indica a expansão da tripanossomose no semiárido do Nordeste, e as informações obtidas poderão esclarecer os fatores epidemiológicos que determinam a ocorrência da tripanossomose por T. vivax na região.(AU)

Risk factors for trypanosomiasis by Trypanosoma vivax in cattle raised in Rio Grande do Norte state / Fatores de risco para tripanossomose por Trypanosoma vivax em bovinos criados no estado do Rio Grande do Norte

The objective of this study was to determine the prevalence of anti Trypanosoma vivax antibodies and the possible risk factors associated with the infection in cattle in Rio Grande do Norte, Northeastern Brazil, through a cross-sectional epidemiological study, with non-probabilistic convenience sampling. A total of 467 cattle's serum samples were analyzed by indirect immunofluorescence. Forty-two samples tested positive for Trypanosoma vivax IgG antibodies, corresponding to the prevalence of 9%. Risk factors influencing the occurrence of trypanosomiasis were milk exploration, raising of European breeds, productivity category: lactation cow, purchase of new cattle, foraging habits near ponds and rivers, and the presence of mechanical vectors. So, high prevalence in beef animals (59.5%), females (95.2%), European breed (88.1%), lactating cows (85.7%), pasture at banks of dams and rivers (95.2%), in addition to the presence of mechanical vectors (81%) and acquisition of animals (88.1%), indicates the expansion of trypanosomiasis in Northeastern semi-arid region, and the information obtained may explain the epidemiological factors that determine the occurrence of trypanosomiasis by T. vivax in this region.(AU)

Objetivando determinar a prevalência de anticorpos anti-Trypanosoma vivax e os possíveis fatores de risco associados à infecção em bovinos no estado do Rio Grande do Norte, nordeste do Brasil, o trabalho consistiu em um estudo epidemiológico transversal, com amostragem não probabilística por conveniência, no qual foram analisadas, por meio da reação de imunofluorescência indireta, 467 amostras de soro sanguíneo de bovinos. Das amostras testadas, 42 foram reagentes para anticorpos IgG anti-Trypanosoma vivax, o que correspondeu à prevalência de 9,0%. Os fatores de risco que influenciaram a ocorrência da tripanossomose foram: exploração com finalidade do tipo leite, criação de bovinos de raça europeia, categoria animal vaca em lactação, aquisição de animais, forrageamento das margens de açudes e rios, além da presença de vetores mecânicos. A alta prevalência encontrada em animais de corte (59,5%), fêmeas (95,2%), raça europeia (88,1%), vacas em lactação (85,7%), pastagem a margens de açudes e rios (95,2%), além da presença de vetores mecânicos (81%) e aquisição de animais (88,1%), indica a expansão da tripanossomose no semiárido do Nordeste, e as informações obtidas poderão esclarecer os fatores epidemiológicos que determinam a ocorrência da tripanossomose por T. vivax na região.(AU)

AUSÊNCIA DE ANTICORPOS EM EQUÍDEOS EXPOSTOS A REBANHOS BOVINOS INFECTADOS POR Trypanosoma vivax

Trypanosoma vivax é hemoprotozoário que acomete especialmente os animais ungulados silvestres e domésticos. Diversos relatos comprovam a ocorrência deste parasita em equídeos na África, sendo os equinos mais susceptíveis que os asininos. Entretanto, o Brasil, mesmo sendo endêmico para a doença em bovinos, existem raros diagnósticos de T. vivax em equídeos. Esse trabalho objetivou verificar a presença de anticorpos anti-T. vivax em equídeos em contato direto com rebanhos bovinos positivos para T. vivax nos estados de MG, SP e CE. Foram testados 154 equídeos para T. vivax através do método de RIFI. Dentre esses, 32 animais apresentaram alterações clínica, como: ataxia, lesões hepáticas e distúrbios reprodutivos. Esses equídeos sintomáticos também foram submetidos a sorologia para T. gondii, N. caninum, T. evansi, T. equi e B. caballi, sendo T. gondii o agente de maior ocorrência. A ausência de resultados positivos para T. vivax indica que equídeos possam ser refratários a esse agente representando uma importância questionável na cadeia epidemiológica da tripanossomose bovina no Brasil.

Trypanosoma vivax is a hemoprotozoan that especially infects wild and domestic ungulate animals. Several reports prove this parasite's occurrence in equids in Africa, but horses more susceptible than donkeys. Although Brazil is endemic for T. vivax cattle disease, there are rare T. vivax diagnoses in equidea. This study aimed to verify the presence of anti-T vivax antibodies in equines living in direct contact with cattle T. vivax positive in MG, SP and CE states. 154 horses were tested for T. vivax using RIFI method. Among these, 32 animals were symptoms, such as: ataxia, liver injury and reproductive disorders. These symptomatic equidae were also subjected to serology exams for T. gondii, N. caninum, T. evansi, T. equi and B. caballi, and T. gondii had been the most frequent agent. The absence of T. vivax positive results indicates equidae may be refractory to this agent, representing a questionable importance in epidemiology bovine trypanosomiasis in Brazil.

Susceptibility of Trypanosoma evansi in the copaiba oil: in vitro test and in mice experimentally infected with the parasite / Susceptibility of Trypanosoma evansi in the copaiba oil: in vitro test and in mice experimentally infected with the parasite

Background: Trypanosoma evansi is a flagellate which belongs to the salivate section, commonly observed parasitizing blood of equines, ruminants, pigs, dogs and wild animals in different regions of the world. It causes many losses to farmers due to death of animals and drug spending in endemic areas. The treatment of this disease in Brazil is only performed with diminazene aceturate; however it has been ineffective for many animals. During the lats years many studies have been carried out with natural products such as the essential oils. Copaiba oil stands out due some properties described as anti-inflammatory, healing, antiedematogenic, antitumor, parasitic and antibacterial. Therefore, this study aimed to test, in vitro and in vivo, the susceptibility of T. evansi to copaiba oil. Materials, Methods & Results: The oils used in this study were obtained from Copaifera reticulata and Copaifera duckei trees, commonly found in the Tapajos National Forest. The procedure received authorization of IBAMA due the scientific purposes. This study identified three oils identified as copaiba 4-C (C. reticulata), copaiba 5-C (C. duckei) and copaiba 8-C (C. reticulata). The bioassay was performed in vitro using specific culture medium for T. evansi, previously described by Baltz, 1985. Copaiba oil was dissolved in dimethyl sulfoxide (DMSO) and tested in three concentrations (0.5, 1.0 and

Background: Trypanosoma evansi is a flagellate which belongs to the salivate section, commonly observed parasitizing blood of equines, ruminants, pigs, dogs and wild animals in different regions of the world. It causes many losses to farmers due to death of animals and drug spending in endemic areas. The treatment of this disease in Brazil is only performed with diminazene aceturate; however it has been ineffective for many animals. During the lats years many studies have been carried out with natural products such as the essential oils. Copaiba oil stands out due some properties described as anti-inflammatory, healing, antiedematogenic, antitumor, parasitic and antibacterial. Therefore, this study aimed to test, in vitro and in vivo, the susceptibility of T. evansi to copaiba oil. Materials, Methods & Results: The oils used in this study were obtained from Copaifera reticulata and Copaifera duckei trees, commonly found in the Tapajos National Forest. The procedure received authorization of IBAMA due the scientific purposes. This study identified three oils identified as copaiba 4-C (C. reticulata), copaiba 5-C (C. duckei) and copaiba 8-C (C. reticulata). The bioassay was performed in vitro using specific culture medium for T. evansi, previously described by Baltz, 1985. Copaiba oil was dissolved in dimethyl sulfoxide (DMSO) and tested in three concentrations (0.5, 1.0 and

Susceptibility of Trypanosoma evansi in the copaiba oil: in vitro test and in mice experimentally infected with the parasite

Background: Trypanosoma evansi is a flagellate which belongs to the salivate section, commonly observed parasitizing blood of equines, ruminants, pigs, dogs and wild animals in different regions of the world. It causes many losses to farmers due to death of animals and drug spending in endemic areas. The treatment of this disease in Brazil is only performed with diminazene aceturate; however it has been ineffective for many animals. During the last years many studies have been carried out with natural products such as the essential oils. Copaiba oil stands out due some properties described as anti-inflammatory, healing, antiedematogenic, antitumor, parasitic and antibacterial. Therefore, this study aimed to test, in vitro and in vivo, the susceptibility of T. evansi to copaiba oil. Materials, Methods & Results: The oils used in this study were obtained from Copaifera reticulata and Copaifera duckei trees, commonly found in the Tapajos National Forest. The procedure received authorization of IBAMA due the scientific purposes. This study identified three oils identified as copaiba 4-C (C. reticulata), copaiba 5-C (C. duckei) and copaiba 8-C (C. reticulata). The bioassay was performed in vitro using specific culture medium for T. evansi, previously described by Baltz, 1985. Copaiba oil was dissolved in dimethyl sulfoxide (DMSO) and tested in three concentrations (0.5, 1.0 and 2.0%) in culture medium containing the parasite. To the control test (without oil) the same volume of DMSO (10 µL) was added. Dimnazene aceturate was also used as a positive control at 0.5% of concentration. The counting of trypanosomes was performed in triplicate in a Neubauer chamber after 1, 3, and 6 hours after the experiment onset. For the tests in vivo, mice were infected (n = 40) and divided in 5 groups of 8 animals each. Group A consisted of healthy animals and Group B comprised animals infected with T. evansi and untreated. The other groups were infected and treated orally with oil of copaíba 4-C (Group C), copaiba 5-C (Group D) and copaiba 8-C (Group E), using a dose of 0.63 mL/kg/day for five consecutive days at intervals of 24 hours. In vitro tests with copaiba oil showed a reduction in the number of alive trypanosomes for the three tested concentrations, when compared to the control test after 1 and 3 h, similar to what occurred with testing aceturate. At 6 hours, it was not observed alive parasites in the test groups, differently from the control group which had an increase of trypanosomes compared to the time zero. The trypanocidal activity had a dose-dependent effect. In the in vivo experiment, the oil of copaiba administered orally had no curative efficacy for any of the groups; however group D treated with C. duckei showed prolonged longevity of the mice when compared to the groups B and C. Discussion: Trypanosoma cruzi and Leishmania amazonensis have been challenged on their susceptibility to oil of copaiba, with obtention of trypanocidal and leishmanicidal effects, similar process thet occurred in this study with T. evansi. According to scientific literature the copaíba oil increases the membrane permeability, as well as provides the depolarization of the mitochondrial membrane in parasite cells. A group of mice in this study showed prolonged longevity, showing that the variation of their compositions influence the trypanocidal effect. Based on these results it was concluded that the T. evansi may is susceptible to the oil of copaiba. Therefore, it can be natural product used as a new alternative and supplementar activity in the treatment of this protozoan, as have been suggested for leishmaniasis.

TRIAGEM E IDENTIFICAÇÃO DE COMPOSTOS PRESENTES NO PATHOGEN BOX® COM ATIVIDADE ANTI-Trypanosoma evansi

CANEVER, M. F. Triagem e Identificação de Compostos Presentes no Pathogen Box® com Atividade Anti-Trypanosoma evansi. 2018. Dissertação (Mestrado em Ciência Animal) - Universidade do Estado de Santa Catarina, Lages, 2018. O parasita Trypanosoma evansi, agente etiológico da surra, possui distribuição cosmopolita e apesar de ser descrito inicialmente como causador da doença em equinos, já existem relatos da infecção em inúmeras espécies domésticas e selvagens (cães, camelos, bovinos, caprinos, capivara, morcegos hematófagos, entre outros). Atualmente o tratamento e profilaxia da doença causada por T. evansi são baseados na administração de fármacos como suramina, aceturato de diminazeno, melarsomina e isometamidium. As principais limitações encontradas no uso desses fármacos estão associadas à toxicidade em algumas espécies, e relatos de cepas resistentes ao tratamento. Com o intuito de encontrar novas alternativas para tratamento de doenças negligenciadas, a Medicines for Malaria Venture desenvolveu o Pathogen Box® - um conjunto de placas contendo quatrocentos compostos distribuídos individualmente em poços. O objetivo deste trabalho foi avaliar a atividade anti-T. evansi de compostos presentes no Pathogen Box® e identificar moléculas que poderão ser utilizadas futuramente no desenvolvimento de novos fármacos para tratamento e profilaxia da surra. Dentre os quatrocentos compostos analisados, sete (pentamidina, MMV688410, MMV687273, MMV022478, MMV688763, MMV676602 e auranofina) apresentaram atividade potencial contra T. evansi reduzindo o número de células em cultivo, sendo que dois desses (pentamidina e MMV688410) também induziram potencialmente a ocorrência de morte por necrose celular. Outros vinte e quadro compostos apresentaram ação intermediária contra T. evansi, dentre os quais, cinco são fármacos já disponíveis no mercado para tratamento de outras afecções. Utilizando dados de citoxicidade celular disponíveis na literatura e no material de apoio do Pathogen Box®, foi possível indicar o composto MMV688410 como o mais promissor para posteriores estudos de novas drogas tripanocidas. O composto MMV688410 provavelmente inibe a triapanotiona redutase, fato que explica sua baixa citotoxidade, uma vez que esse alvo é exclusivo de tripanossomatídeos, além disso induziu tanto a redução do número de parasitas em cultivo como a morte dos parasitas por necrose celular. Os resultados obtidos neste trabalho fornecem dados promissores para o estudo de novas drogas tripanocidas. Mais pesquisas são necessárias para melhor determinar a ação dos compostos encontrados contra T. evansi.

CANEVER, M. F. Screening and Identification of Compounds Present in Pathogen Box® with anti-Trypanosoma evansi Activity. 2018. Dissertação (Mestrado em Ciência Animal) - Universidade do Estado de Santa Catarina, Lages, 2018. The parasite Trypanosoma evansi, an etiological agent of surra, has a cosmopolitan distribution and although it is initially described as causing the disease in horses, there are reports of infection in innumerable domestic and wild species (dogs, camels, cattle, caprines, capybara, bats, among others). Currently the treatment and prophylaxis of the disease caused by T. evansi are based on the administration of drugs such as suramin, diminazene aceturate, melarsomine and isometamidium. The main limitations in the use of these drugs are associated with toxicity in some species, and reports of treatment resistant strains. In order to find new alternatives for treatment of neglected diseases, Medicines for Malaria Venture developed the Pathogen Box® - a set of plates containing four hundred compounds distributed individually in wells. The objective of this work was to evaluate the anti-T. evansi activity of compounds present in the Pathogen Box® and to identify molecules that could be used in the future in the development of new drugs for treatment and prophylaxis of surra. Among the four hundred compounds analyzed, seven (pentamidine, MMV688410, MMV687273, MMV022478, MMV688763, MMV676602 and auranofin) showed potential activity against T. evansi, reducing the number of cells in culture, two of which (pentamidine and MMV688410) also potentially induced occurrence of death by cellular necrosis. Twenty other compounds showed intermediate action against T. evansi, of which five are drugs already available in the market for treatment of other conditions. Using cell cytotoxicity data available in the literature and in Pathogen Box® support material, it was possible to indicate compound MMV688410 as the most promising for further studies of novel trypanocidal drugs. The compound MMV688410 probably inhibits triapanoethione reductase, which explains its low cytotoxicity, since this target is unique to trypanosomatids, in addition it induced both the reduction of the number of parasites in culture and the death of the parasites by cellular necrosis. The results obtained in this work provide promising data for the development of new trypanocidal drugs, but more studies are needed to better determine the action of the compounds found against T. evansi.

PADRONIZAÇÃO DE UM ANTÍGENO TAMPONADO PARA PESQUISA DE ANTICORPOS ANTI -Trypanosoma evansi EM EQUINOS

Surra, também conhecida como Mal das Cadeiras na América Latina, é uma doença infecciosa causada pelo Trypanosoma evansi (T. evansi). Descrita primariamente nas regiões tropicais e subtropicais da África, Ásia, América Central, acomete grande número de espécies de animais domésticos e selvagens (equinos, camelídeos bovinos, búfalos, ovinos, caprinos, suínos, felinos, cães, capivaras e morcegos hematófagos), causando morte de animais, diminuição da produção e elevados e gastos com tratamentos. No Brasil não existem dados oficiais acerca da circulação do agente, apenas estudos regionalizados. Santa Catarina é considerada zona livre da doença. O controle da infecção está baseado no diagnóstico rápido seguido do tratamento dos animais doentes. O exame microscópico direto, é o teste mais utilizado para o diagnóstico da infecção no Brasil, entretanto, apresenta baixa especificidade e sensibilidade, levando possivelmente ao sub - diagnóstico da infecção, principalmente na fase crônica. Assim, o objetivo deste trabalho é avaliar um ensaio de soroaglutinação rápida (SAR/Te) para sorodiagnóstico de triagem da infecção por T. evansi em equinos. Além disso, este estudo descreve as características clínicas, parasitológicas e hematobioquímicas no primeiro caso autóctone de surra em equinos no Estado de Santa Catarina, Brasil. Deste modo, esta proposta visa contribuir com as estratégias de vigilância e controle da surra no país.

Trypanosoma evansi is the causative agent of surra or Mal das Caderas (in Brazil). The disease is present in Africa, Asia and Latin America. It can affect a very large range of domestic and wild hosts ( equines, camelids, cattle, buffaloes, sheep, goats, pigs, dogs, capybaras and vampire bats) causing high mortality, decrease of production and expenses with treatments. In Brazil, there are no epizootiological data on the circulation of the agent, only regionalized studies. Santa Catarina State is considered a free zone of trypanosomiasis. The disease control, is based on rapid diagnosis of infection followed by treatment of animals. Direct microscopic examination is the primary test for the diagnosis of infection in Brazil, however, it presents low specificity and sensitivity, possibly leading to underdiagnosis of infection, mainly in the chronic stage. Thus, the main aim of this study is to evaluate a rapid test of serum agglutination for diagnosis of T. evansi infection in horses. In addition, this work describes the clinical, parasitological and haemato biochemical parameters in the first autochthonous outbreak of Surra in horses in the State of Santa Catarina, Brazil.

Experimental Infection by Tripanossoma evansi in Rabbits: Levels of Sodium, Potassium, Calcium and Phosphorus in Serum

Background: Trypanosoma evansi is the most widely distributed of the pathogenic African animal trypanosomes, affecting domestic livestock and wildlife in country. The animals presented clinical sings as anemia, emaciation, apathy, recurrent fever , enlarged lymph nodes, edema and abortion The minerals have different functions in the organism, and an imbalance, either by excess or deficiency, or a pathological condition, causes alterations in the respective serum levels, as well as in trypanosomosis. Therefore, the aim of this study was to evaluate the concentrations of sodium, potassium, calcium and phosphorus in blood serum of rabbits experimentally infected with Trypanosoma evansi. Materials, Methods & Results: Twelve adult female Oryctolagus cuniculus, weighing average 3.9 kg, were used. Rabbits were divided into two groups, a control group with six animals (rabbits 1-6) and an infected group with six animals (rabbits 7-12). Animals from trypanosome-infected groups were inoculated intraperitoneally with 0.5 mL of rat blood containing 10 8 trypanosomes (Day 1). Control group received physiological solution by the same route. Parasitemia was estimated daily for 118 days post- inoculation (PI) by microscopic examination of smears. Blood samples for hematology and evaluation of serum minerals were collected at days 1, 5, 20, 35, 50, 80 and 118 PI. Hematocrit was evaluated for monitoring of the disease. Inductively coupled plasma optical emission spectrometry (ICP OES) was used to measure the levels of sodium, potassium, calcium and phosphorus. Hyporexia, edema and fever were clinical signs associated with change in the levels of the minerals. A decrease in the number of red blood cells was only observed at day 5 post-inoculation. Significant differences were observed among groups (P < 0.05) in minerals levels. Sodium and calcium were reduced at days 35, 50, 80 and 118 PI. [...]

Experimental Infection by Tripanossoma evansi in Rabbits: Levels of Sodium, Potassium, Calcium and Phosphorus in Serum

Background: Trypanosoma evansi is the most widely distributed of the pathogenic African animal trypanosomes, affecting domestic livestock and wildlife in country. The animals presented clinical sings as anemia, emaciation, apathy, recurrent fever , enlarged lymph nodes, edema and abortion The minerals have different functions in the organism, and an imbalance, either by excess or deficiency, or a pathological condition, causes alterations in the respective serum levels, as well as in trypanosomosis. Therefore, the aim of this study was to evaluate the concentrations of sodium, potassium, calcium and phosphorus in blood serum of rabbits experimentally infected with Trypanosoma evansi. Materials, Methods & Results: Twelve adult female Oryctolagus cuniculus, weighing average 3.9 kg, were used. Rabbits were divided into two groups, a control group with six animals (rabbits 1-6) and an infected group with six animals (rabbits 7-12). Animals from trypanosome-infected groups were inoculated intraperitoneally with 0.5 mL of rat blood containing 10 8 trypanosomes (Day 1). Control group received physiological solution by the same route. Parasitemia was estimated daily for 118 days post- inoculation (PI) by microscopic examination of smears. Blood samples for hematology and evaluation of serum minerals were collected at days 1, 5, 20, 35, 50, 80 and 118 PI. Hematocrit was evaluated for monitoring of the disease. Inductively coupled plasma optical emission spectrometry (ICP OES) was used to measure the levels of sodium, potassium, calcium and phosphorus. Hyporexia, edema and fever were clinical signs associated with change in the levels of the minerals. A decrease in the number of red blood cells was only observed at day 5 post-inoculation. Significant differences were observed among groups (P < 0.05) in minerals levels. Sodium and calcium were reduced at days 35, 50, 80 and 118 PI. [...](AU)

Suscetibilidade de Trypanosoma evansi à anfotericina B

The aim of this study was to evaluate the Trypanosoma evansi susceptibility to amphotericin B in vitro and in vivo. Four concentrations (0.06, 0.25, 1.0, and 4.0µg mL-1) of amphotericin B were tested against a suspension containing T. evansi and phosphate buffer solution with glucose in the in vitro assay. Fifteen rats infected with T. evansi were used for the in vivo assay. Groups A (n=5) and B (n=5) received daily doses of 1 and 3mg kg-1 during 10 days and the parasitemia was estimated daily by microscopic examination of smears. The rats from group C (n=5) were the positive control and were infected but not treated. Rats from group D (n=5) were used as negative control. in vitro assays showed a 100% of susceptibility of T. evansi to amphotericin B after 7 hours, at all concentrations tested. The higher dose tested did not cure the rats, although treated rats had a longer life span in comparison to the non-treated group. Adverse effects on renal and hepatic hemodynamics were also researched. Biochemical parameters obtained were within the normal ranges. It was concluded that T. evansi is susceptible to amphotericin B in vitro. The dose of 3 mg kg-1 tested in rats increased life span, but did not cure the animals.

O objetivo deste estudo foi avaliar a suscetibilidade do Trypanosoma evansi in vitro e in vivo à anfotericina B. Nos testes in vitro, foram utilizadas quatro concentrações (0,06; 0,25; 1,0; 4,0µg mL-1) de anfotecicina B frente a uma suspensão de T. evansi em solução tampão fosfato rico em glicose (PBS - glicose). Para avaliar a eficácia in vivo, foram utilizados 15 ratos parasitados com T. evansi. Em dois grupos de cinco ratos infectados, doses únicas diárias de 1 (grupo A) e de 3mg kg-1 (grupo B) foram administradas via intraperitonial durante 10 dias, e a parasitemia foi avaliada por meio de esfregaço sanguíneo. Grupo C (n=5) foi utilizado como grupo controle positivo, infectados com T. evansi e não tratados, e o grupo D (n=5), como controle negativo. Os ensaios in vitro evidenciaram suscetibilidade de 100% do T. evansi à anfotericina B após 7h, em todas as concentrações avaliadas. Nos ratos, nem a maior dose testada curou os roedores, apesar de ter prolongado a vida destes em comparação à vida dos animais infectados, mas não tratados. Foi também investigada a função hepática e renal dos ratos após a terapia, e os parâmetros bioquímicos analisados mantiveram-se dentro da normalidade. Conclui-se que o T. evansi in vitro é suscetível à anfotericina B. A dose 3mg kg-1 testada aumentou a expectativa de vida de ratos infectados, porém não teve efeito curativo.

Suscetibilidade de Trypanosoma evansi à anfotericina B

The aim of this study was to evaluate the Trypanosoma evansi susceptibility to amphotericin B in vitro and in vivo. Four concentrations (0.06, 0.25, 1.0, and 4.0µg mL-1) of amphotericin B were tested against a suspension containing T. evansi and phosphate buffer solution with glucose in the in vitro assay. Fifteen rats infected with T. evansi were used for the in vivo assay. Groups A (n=5) and B (n=5) received daily doses of 1 and 3mg kg-1 during 10 days and the parasitemia was estimated daily by microscopic examination of smears. The rats from group C (n=5) were the positive control and were infected but not treated. Rats from group D (n=5) were used as negative control. in vitro assays showed a 100% of susceptibility of T. evansi to amphotericin B after 7 hours, at all concentrations tested. The higher dose tested did not cure the rats, although treated rats had a longer life span in comparison to the non-treated group. Adverse effects on renal and hepatic hemodynamics were also researched. Biochemical parameters obtained were within the normal ranges. It was concluded that T. evansi is susceptible to amphotericin B in vitro. The dose of 3 mg kg-1 tested in rats increased life span, but did not cure the animals.

O objetivo deste estudo foi avaliar a suscetibilidade do Trypanosoma evansi in vitro e in vivo à anfotericina B. Nos testes in vitro, foram utilizadas quatro concentrações (0,06; 0,25; 1,0; 4,0µg mL-1) de anfotecicina B frente a uma suspensão de T. evansi em solução tampão fosfato rico em glicose (PBS - glicose). Para avaliar a eficácia in vivo, foram utilizados 15 ratos parasitados com T. evansi. Em dois grupos de cinco ratos infectados, doses únicas diárias de 1 (grupo A) e de 3mg kg-1 (grupo B) foram administradas via intraperitonial durante 10 dias, e a parasitemia foi avaliada por meio de esfregaço sanguíneo. Grupo C (n=5) foi utilizado como grupo controle positivo, infectados com T. evansi e não tratados, e o grupo D (n=5), como controle negativo. Os ensaios in vitro evidenciaram suscetibilidade de 100% do T. evansi à anfotericina B após 7h, em todas as concentrações avaliadas. Nos ratos, nem a maior dose testada curou os roedores, apesar de ter prolongado a vida destes em comparação à vida dos animais infectados, mas não tratados. Foi também investigada a função hepática e renal dos ratos após a terapia, e os parâmetros bioquímicos analisados mantiveram-se dentro da normalidade. Conclui-se que o T. evansi in vitro é suscetível à anfotericina B. A dose 3mg kg-1 testada aumentou a expectativa de vida de ratos infectados, porém não teve efeito curativo.

Aceturato de diminazeno e dipropionato de imidocarb no controle de infecção por Trypanosoma evansi em Rattus norvegicus infectados experimentalmente / Diminazene aceturate and imidocarb dipropionate in the control of Trypanosoma evansi infection in Rattus norvegicus experimentally infected

Este estudo teve como objetivo avaliar o efeito do aceturato de diminazeno e do dipropionato de imidocarb no controle da infecção por Trypanosoma evansi em ratos (Rattus norvegicus) infectados experimentalmente. Cinqüenta e quatro ratos machos foram inoculados via intraperitonial com 104 tripomastigotas de T. evansi/animal. Os ratos foram monitorados diariamente por meio de esfregaço sanguíneo periférico. No momento em que se observassem oito protozoários por campo microscópico de 1000x, era iniciado o tratamento com as drogas (dia zero). O estudo foi dividido em dois protocolos terapêuticos e os fármacos foram administrados via intramuscular. O primeiro protocolo foi aplicado nos grupos A, B, C e D e o segundo protocolo nos grupos E, F, G e H. O grupo controle foi identificado como grupo I, não medicados. No primeiro protocolo, os ratos receberam uma dose única dos fármacos no dia zero e sempre que se observasse T. evansi na circulação periférica. No segundo protocolo, os roedores receberam as mesmas doses, no entanto, por cinco dias consecutivos. No primeiro protocolo, os dois princípios ativos não apresentaram eficácia curativa, ocorrendo reincidência da parasitemia após alguns dias do tratamento. No segundo protocolo, o aceturato de diminazeno eliminou a forma tripomastigota da circulação e os ratos foram eutanasiados após 90 dias do início do tratamento. Os roedores tratados com dipropionato de imidocarb apresentaram recidiva da infecção após 30 dias. Na histopatologia não se observou alteração renal e hepática relacionada à doença ou aos medicamentos testados. Com base nos resultados, foi concluído que o aceturato de diminazeno, quando administrado por cinco dias consecutivos, é efetivo no tratamento da tripanossomose em ratos.(AU)

The aim of this study was to evaluate the efficacy of diminazene aceturate and imidocarb dipropionate in the control of Trypanosoma evansi infection in rats (Rattus norvegicus) experimentally infected. Fifty-four male rats were inoculated through intraperitoneal route with 104 T. evansi trypomastigotes. The rats were evaluated daily by periferic blood smears examination and treated when eight flagellated parasites were observed in 1000x microscopic field. Two therapeutics protocols were used. The first one included Groups A, B, C, D in which the rats were submitted to a single dose of the testing drugs administered by intramuscular route at the day 0 and again when T. evansi was observed in the blood smears. The rats of the second protocol (Groups E, F, G, H) were submitted to the same treatment by five consecutive days. Four rats (Group I) were used as control and were not submitted to any treatment. Tested drugs did not show any curative effect when used in the first protocol, since parasitaemia was evident few days after treatment. The use of diminazene aceturate in the second protocol resulted in elimination of the trypomastigotes from circulation. In this case the rats were euthanized at the day 90. The infection recurred 30 days after the administration of imidocarb dipropionate. Histologically, no lesions were found in the liver or kidney. Diminazene aceturate is effective in treating trypanosomosis in rats when used five days consecutively.(AU)

Trypanosoma vivax nos tecidos testicular e epididimário de ovinos experimentalmente infectados / Trypanosoma vivax in testicular and epidydimal tissues of experimentally infected sheep

Quatro ovinos machos, com cerca de 12 meses de idade (Ovinos 1-4), foram infectados por via intravenosa com aproximadamente 1,25x10(5) tripomastigotas de Trypanosoma vivax, outros quatro ovinos (Ovinos 5-8) destinaram-se ao grupo controle. Após a infecção, exames clínicos visando avaliar temperatura retal, freqüências cardíaca e respiratória e parasitemia foram realizados diariamente por 30 dias, tempo estabelecido para o término do experimento. A avaliação do hematócrito foi realizada a cada cinco dias. Ao final do período experimental, os animais foram castrados e os testículos e epidídimos submetidos ao exame anatomopatológico. Amostras destes órgãos dos Ovinos 1, 4 e 5 foram tomadas para a realização da reação em cadeia da polimerase (PCR). Os parâmetros clínicos (hipertermia, aumento das freqüências cardíaca e respiratória, aumento de volume dos linfonodos e palidez das mucosas) mantiveram-se para o grupo infectado acima dos valores mostrados pelo grupo controle durante todo o período experimental. A parasitemia foi observada a partir do 3º dia pós-infecção (dpi) com picos nos 6-10os dpi e nos 15-18os dpi. Os Ovinos 1 e 4 apresentaram, a partir do 25º dpi, anemia acentuada. Macroscopicamente, todos os testículos dos animais do grupo infectado apresentaram-se flácidos e com coloração pálida. Microscopicamente, observaram-se degeneração testicular moderada a acentuada, epididimite multifocal e hiperplasia do epitélio epididimário. A análise por PCR de T. vivax nos tecidos testicular e epididimário resultou em 100% de positividade para ovinos infectados experimentalmente. As lesões epididimárias e testiculares associadas à presença do parasita nesses órgãos, detectada por PCR, sugerem a participação do parasita no mecanismo etiopatogênico de danos reprodutivos.(AU)

Four adult sheep (number 1, 2, 3 and 4), all males, were inoculated intravenously with 1ml of blood containing 1.25x10(5) trypomastigotes of Trypanosoma vivax, and Sheep 5, 6, 7 and 8 were used as control. After infection, clinical exams considering rectal temperature, respiratory and cardiac frequencies, and parasitaemia were recorded daily for a 30-day experiment period. Blood samples were obtained for 5-day intervals to hematocrit analysis. At the end of the experimental period, the sheep were orquiectomized. Testes and epididymides from these animals were studied anatomopathologically. Samples from these tissues of Sheep 1, 4 and 5 were taken to polymerase chain reaction (PCR). Clinical parameters remained for the infected group above the values observed in the control group during the experimental period. Parasitaemia was observed on day 3 post-infection, and the highest values occurred between day 6 and 10, and day 15 and 18 post-infection. Sheep 1 and 4 showed severe anemia on day 25 post-infection. All sheep of the infected group showed flabby and palid testes. Histologically, moderate to severe testicular degeneration, multifocal epididymitis and hyperplasia of epididymal epithelium were observed. The result of T. vivax PCR analysis in the testes and epididymal tissues was positive in 100% of the samples of the experimentally infected sheep. Epididymal and testicular lesions associated with the presence of the parasite in these tissues, shown by PCR, suggest the participation of T. vivax in the pathophysiological mechanism of reproductive damage.(AU)

Susceptibility of Trypanosoma evansi in the copaiba oil: in vitro test and in mice experimentally infected with the parasite / Susceptibility of Trypanosoma evansi in the copaiba oil: in vitro test and in mice experimentally infected with the parasite

Background: Trypanosoma evansi is a flagellate which belongs to the salivate section, commonly observed parasitizing blood of equines, ruminants, pigs, dogs and wild animals in different regions of the world. It causes many losses to farmers due to death of animals and drug spending in endemic areas. The treatment of this disease in Brazil is only performed with diminazene aceturate; however it has been ineffective for many animals. During the lats years many studies have been carried out with natural products such as the essential oils. Copaiba oil stands out due some properties described as anti-inflammatory, healing, antiedematogenic, antitumor, parasitic and antibacterial. Therefore, this study aimed to test, in vitro and in vivo, the susceptibility of T. evansi to copaiba oil. Materials, Methods & Results: The oils used in this study were obtained from Copaifera reticulata and Copaifera duckei trees, commonly found in the Tapajos National Forest. The procedure received authorization of IBAMA due the scientific purposes. This study identified three oils identified as copaiba 4-C (C. reticulata), copaiba 5-C (C. duckei) and copaiba 8-C (C. reticulata). The bioassay was performed in vitro using specific culture medium for T. evansi, previously described by Baltz, 1985. Copaiba oil was dissolved in dimethyl sulfoxide (DMSO) and tested in three concentrations (0.5, 1.0 and

Background: Trypanosoma evansi is a flagellate which belongs to the salivate section, commonly observed parasitizing blood of equines, ruminants, pigs, dogs and wild animals in different regions of the world. It causes many losses to farmers due to death of animals and drug spending in endemic areas. The treatment of this disease in Brazil is only performed with diminazene aceturate; however it has been ineffective for many animals. During the lats years many studies have been carried out with natural products such as the essential oils. Copaiba oil stands out due some properties described as anti-inflammatory, healing, antiedematogenic, antitumor, parasitic and antibacterial. Therefore, this study aimed to test, in vitro and in vivo, the susceptibility of T. evansi to copaiba oil. Materials, Methods & Results: The oils used in this study were obtained from Copaifera reticulata and Copaifera duckei trees, commonly found in the Tapajos National Forest. The procedure received authorization of IBAMA due the scientific purposes. This study identified three oils identified as copaiba 4-C (C. reticulata), copaiba 5-C (C. duckei) and copaiba 8-C (C. reticulata). The bioassay was performed in vitro using specific culture medium for T. evansi, previously described by Baltz, 1985. Copaiba oil was dissolved in dimethyl sulfoxide (DMSO) and tested in three concentrations (0.5, 1.0 and

Relationship between parasitemia and leukogram in Trypanosoma evansi infected cats / Relação parasitemia e leucograma de gatos infectados com Trypanosoma evansi

Trypanosoma evansi is a protozoan which causes trypanosomosis in livestock in many countries of Southeast Asia, Africa and South America. We chose to use cats in our study due to the facility to handle the animals and the lack of studies involving the trypanosomosis in this species. The aim of this study was to analyze the leukogram of domestic cats experimentally infected with T. evansi and its correlation to the parasitemia. Thirteen animals were divided into two groups. Seven animals were infected with T. evansi and six were used as negative control. Parasitemia was estimated daily by microscopic examination of smears. Blood samples for leukogram were collected at days 0, 7, 21, 35 and 49. The parasitemia peak was recorded at day five post-inoculation. Thereafter, irregular waves of parasitemia were observed, ranging from zero to three trypomastigotes per microscopic field. Increased number of total leukocytes (day 49), monocytes (days 7, 35 and 49), segmented (day 49) and nonsegmented neuthrophils (day 35), and decreased number of lymphocytes and eosinophils (days 21, 35 and 49) were observed (P 0.05). Cats infected with T. evansi have leukocytosis, neutrophilia, monocytosis, lymphopenia and eosinopenia. However, no relationship between parasitemia peaks and white blood cells was observed, except by the monocytes in day 7.

Trypanosoma evansi é um protozoário que causa a tripanossomose em animais de muitos países do sudeste da Ásia, África e América do Sul. Optamos por utilizar os gatos em nosso estudo, devido à facilidade de manipular os animais e a falta de estudos envolvendo a tripanossomose nesta espécie. Deste modo, o objetivo deste estudo foi investigar alterações no leucograma de felinos domésticos infectados experimentalmente por T. evansi e relacionar com a parasitemia. Foram utilizados 13 gatos, divididos em dois grupos. Sete deles foram infectados com T. evansi e o restante foram utilizados como grupo controle negativo. Os animais foram monitorados diariamente através de esfregaço sanguíneo. Nos dias 0, 7, 21, 35 e 49 de experimento, foram coletadas amostras de sangue para avaliação do leucograma. O pico de parasitemia ocorreu cinco dias após inoculação, após este período o número de parasitos reduziu e manteve-se com picos irregulares, variando de zero a três tripomastigotas/campo. Na pesquisa foi verificado aumento (P 0,05) do número de leucócitos totais (dia 49), bastonetes (dia 35), neutrofilos segmentados (dia 49) e monócitos (dias 7, 35 e 49) e redução de linfocitos e eosinofilos (dias 21, 35 e 49). Gatos infectados com T. evansi apresentam leucocitose, neutrofilia, monocitose, linfopenia e eosinopenia. Porém, não foi verificado relação entre os picos de parasitemia e alteraç

Relationship between parasitemia and leukogram in Trypanosoma evansi infected cats / Relação parasitemia e leucograma de gatos infectados com Trypanosoma evansi

Trypanosoma evansi is a protozoan which causes trypanosomosis in livestock in many countries of Southeast Asia, Africa and South America. We chose to use cats in our study due to the facility to handle the animals and the lack of studies involving the trypanosomosis in this species. The aim of this study was to analyze the leukogram of domestic cats experimentally infected with T. evansi and its correlation to the parasitemia. Thirteen animals were divided into two groups. Seven animals were infected with T. evansi and six were used as negative control. Parasitemia was estimated daily by microscopic examination of smears. Blood samples for leukogram were collected at days 0, 7, 21, 35 and 49. The parasitemia peak was recorded at day five post-inoculation. Thereafter, irregular waves of parasitemia were observed, ranging from zero to three trypomastigotes per microscopic field. Increased number of total leukocytes (day 49), monocytes (days 7, 35 and 49), segmented (day 49) and nonsegmented neuthrophils (day 35), and decreased number of lymphocytes and eosinophils (days 21, 35 and 49) were observed (P 0.05). Cats infected with T. evansi have leukocytosis, neutrophilia, monocytosis, lymphopenia and eosinopenia. However, no relationship between parasitemia peaks and white blood cells was observed, except by the monocytes in day 7.

Trypanosoma evansi é um protozoário que causa a tripanossomose em animais de muitos países do sudeste da Ásia, África e América do Sul. Optamos por utilizar os gatos em nosso estudo, devido à facilidade de manipular os animais e a falta de estudos envolvendo a tripanossomose nesta espécie. Deste modo, o objetivo deste estudo foi investigar alterações no leucograma de felinos domésticos infectados experimentalmente por T. evansi e relacionar com a parasitemia. Foram utilizados 13 gatos, divididos em dois grupos. Sete deles foram infectados com T. evansi e o restante foram utilizados como grupo controle negativo. Os animais foram monitorados diariamente através de esfregaço sanguíneo. Nos dias 0, 7, 21, 35 e 49 de experimento, foram coletadas amostras de sangue para avaliação do leucograma. O pico de parasitemia ocorreu cinco dias após inoculação, após este período o número de parasitos reduziu e manteve-se com picos irregulares, variando de zero a três tripomastigotas/campo. Na pesquisa foi verificado aumento (P 0,05) do número de leucócitos totais (dia 49), bastonetes (dia 35), neutrofilos segmentados (dia 49) e monócitos (dias 7, 35 e 49) e redução de linfocitos e eosinofilos (dias 21, 35 e 49). Gatos infectados com T. evansi apresentam leucocitose, neutrofilia, monocitose, linfopenia e eosinopenia. Porém, não foi verificado relação entre os picos de parasitemia e alteraç