Orientador: Rosangela Zacarias Machado / Banca: Nadia Regina Pereira Almosny / Banca: Natalino Hajime Yoshinari / Banca: Jose Mauricio Barbanti Duarte / Banca: Karin Werther / Resumo: Doenças transmitidas por vetores artrópodes são mundialmente importantes para a saúde humana e animal. Recentemente, diversos estudos têm sido realizados a fim de investigar o possível papel dos animais selvagens na epidemiologia destas enfermidades. A identificação de reservatórios selvagens para estes hemoparasitas ajudaria no entendimento da epi enfermidades por eles causadas, principalmente aquelas de caráter zoonótico. O presente estudo teve como objetivo pesquisar em amostras de sangue de carnívoros selvagens mantidos em cativeiro a presença de infecção ou exposição a agentes Anaplasmataceae (Ehrlichia canis, E. chaffeensis, E. ewingii, Neorickettsia risticii, N. helminthoeca, Anaplasma platys e A. phagocytophilum), Rickettsiaceae (Orientia tsutsugamushi e Rickettsia sp. dos Grupos da Febre Maculosa e do Tifo), Babesia sp., Cytauxzoon sp. (somente para os felídeos), micoplasmas hemotróficos (Mycoplasma haemofelis, Candidatus M. haemominutum, Candidatus M. turicensis, M. haemocanis e Candidatus M. haematoparvum) e Hepatozoon sp., utilizando métodos sorológicos e moleculares. Para tal, foram amostrados 167 felídeos e 100 canídeos selvagens mantidos em cativeiro nos estados de São Paulo, Mato Grosso e Distrito Federal. Doze felídeos (7,2%) e três (3%) canídeos mostraram-se soropositivos frente ao antígeno de E. canis. Apenas um canídeo (1%) mostrou-se soropositivo para A. phagocytophilum. Nenhum animal mostrou-se soropositivo para E. chaffeensis ou N. risticii. A análise filogenética baseada em um fragmento de 350 pb do gene 16S rRNA não foi suficientemente robusta para diferenciar entre as espécies de Ehrlichia spp. Os fragmentos de DNA de Ehrlichia spp. encontrados em quatro felídeos foram posicionados em um ramo distinto daquela de E. canis e E. chaffeensis, com base... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Vector-borne diseases are worldwide important to human and animal health. Recently, several studies have been done aiming to investigate the role of wild animals in the epidemiology of these diseases. The identification of wild reservoirs for these hemoparasites would help in a better understanding of the epidemiology of these diseases, mainly that with zoonotic character. The present work aimed to investigate the presence of infection or exposure to Anaplasmataceae (Ehrlichia canis, E. chaffeensis, E. ewingii, Neorickettsia risticii, N. helminthoeca, Anaplasma platys e A. phagocytophilum) and Rickettsiaceae (Orientia tsutsugamushi and Spotted Fever and Typhus Group Rickettsia sp.), Babesia sp., Cytauxzoon sp., hemotrophic hemoplasmas (Mycoplasma haemofelis, Candidatus M. haemominutum, Candidatus M. turicensis, M. haemocanis e Candidatus M. haematoparvum) and Hepatozoon sp. in captive wild carnivores blood samples by molecular and serological methods. Blood samples were collected from 167 wild felids and 100 wild canids, maintained in captivity in zoos from São Paulo and Mato Grosso states, and Distrito Federal. Twelve felids (7.2%) and three canids (3%) were seropositive to E. canis. Only one canid (1%) was seropositive to A. phagocytophilum. None was seropositive to E. chaffeensis neither N. risticii. The phylogenetic analysis of 350bp of 16S rRNA gene was not sufficiently robust to support the differentiation of Ehrlichia species. The Ehrlichia spp. DNA found in four felids was in a distinct clade from E. chaffeensis and E. canis by omp-1 phylogenetic analysis. The phylogenetic analysis of dsb gene showed the infection by E. canis in one sampled crab-eating fox. Seventeen felids (10%) and ten canids (10%) was positive to Anaplasma spp. PCR, which was in the same clade than A. phagocytophilum and A. platys by... (Complete abstract click electronic access below) / Doutor

Please read the abstract in the section 00front of this document / Canine babesiosis, caused by the tick-borne protozoan Babesia canis rossi, is an economically important and potentially fatal disease of dogs in South Africa. The host's response to many infectious diseases is mediated (at least in part) by intercellular messengers called cytokines. One of the most important cytokines released is tumour necrosis factor (TNF). A study was designed to measure serum concentrations of TNF in dogs naturally infected with canine babesiosis and to relate TNF concentrations to clinical severity, mortality, rectal temperature and parasitaemia. There was a statistically significant difference in TNF concentrations between groups of differing disease severity, with a general trend of increasing mean 10g(TNF) with increasing severity of disease. A noteworthy finding was that dogs with hypoglycaemia had very high TNF (mean 15.03 nglml compared to a mean of 2.32 nglml for other sick dogs without hypoglycaemia). When TNF values were compared between survival and non-survival groups, there was no significant difference. The rectal temperature of the dogs in this study did not show any statistically significant association with TNF concentrations. When parasitaemia and TNF were examined within groups of infected dogs, there was no significant relationship. However, when the sample size was increased by pooling all infected dogs and treating them as a single group, there was a highly significant positive correlation (p = 0.003) between parasitaemia and serum TNF concentrations. The results ofthis study were encouraging and indicate that canine babesiosis may share a similar pathophysiology with human malaria in terms ofTNF being associated with disease severity. One ofthe most significant findings in this study was the presence ofvery high TNF values in two ofthree dogs with hypoglycaemia. Hypoglycaemia has not been previously recorded in dogs with babesiosis and is a potentially important finding particularly in view ofthe hypoglycaemia associated with malaria in humans. Malarial hypoglycaemia is correlated with a higher mortality in humans, especially in pregnant women and children. If the findings ofthis study can be Vl confinned and expanded, they may lend further support to the use of canine babesiosis as a model for some ofthe problems encountered in human malaria research. / Dissertation (MMed Vet (Med))--University of Pretoria, 2001. / Companion Animal Clinical Studies / unrestricted

A hypercoagulable state has been demonstrated in human falciparum malaria in mild and complicated forms of the disease. Disseminated intravascular coagulation (DIC) was implicated by some authors, but deemed a rare occurrence by others. The possibility of coagulopathy in Babesia canis rossi infections in the canine patient has also been suggested in the literature, but minimal work has been done to evaluate the clinicopathological nature of it in further detail. In the canine babesiosis (CB) pathogenesis thought-process, DIC has been implicated. A DIC-like syndrome, as evidenced by intravascular fibrin deposition and haemorrhage into muscles and tissues was found at post mortem in one study. On the basis of these findings, it was postulated that DIC might be a serious complication of severe Babesia infection in the dog. Clinical DIC (haemorrhagic diathesis) is however seldom seen. It was also hypothesised in the literature that the multiple organ dysfunction syndrome (MODS) demonstrated in the complicated form of Babesia was caused, in addition to tissue damage due to local hypoxia, by microthrombi as a result of a coagulopathy. This needs to be further investigated. Pulmonary thromboembolism (PTE) has not been implicated in CB, however thromboemboli in the lungs were found in dogs with immune-mediated haemolytic anaemia (IMHA) for which a similar mechanism of venous stasis, hypercoagulability and endothelial damage (as found in CB) is proposed. In humans, PTE is believed to be a major underdiagnosed contributor to mortality in 5 to 15% of hospitalised adults. If early diagnosis of PTE can be achieved, the mortality rate can certainly be decreased. A similar situation with resultant serious implications in complicated CB cases may exist. Clinically, PTE is suspected if a patient with a known prothrombotic condition develops sudden dyspnoea and tachypnoea. These clinical symptoms are frequently seen in complicated CB patients and may, in addition to being a compensatory mechanism for the metabolic acidosis and anaemia, be attributed to thrombus-induced mechanical changes in lung function. Pulmonary scintigraphy provides a sensitive means of diagnosing PTE. It was (and some authors still do) believed that a ventilation scintigraphic scan should be done in association with a perfusion scan to increase the specificity and accuracy of diagnoses. However, authors of the recent PISA-PED study in humans proposed that the sensitivity and specificity of a perfusion scan, without a ventilation scan, in patients with suspected PTE was sufficient. The incidence of PTE or the use of pulmonary perfusion scintigraphy in CB dogs has never been studied. The objective of this study was to prospectively evaluate the scintigraphic pulmonary perfusion pattern in hospitalised Babesia dogs in an attempt to ascertain whether a scintigraphic pattern consistent with PTE does indeed occur in these patients. The study consisted of a normal control group of nine mature healthy Beagle dogs aged 36 – 43 months and weighing 9.9 – 15kg and a Babesia group with 14 dogs of a variety of breeds that were naturally infected with Babesia, aged 6 – 103 months and weighing 6.3 – 25.5kg. Pulmonary perfusion scintigraphy was performed after making thoracic radiographs and performing a blood gas analysis in both groups. The scintigraphic images were visually inspected for changes suggestive of PTE. Surprisingly, not a single dog in the Babesia group had segmental or wedge-shaped perfusion defects which would have resulted in a high probability for PTE. The scintigraphic pulmonary perfusion pattern demonstrated was not significantly different between the two groups (p = 1.00). Many dogs in both groups had a mottled appearance on the right and left dorsal oblique images, which was not believed to be consistent with clinically relevant PTE. This study provides baseline data that may be used to further investigate the pulmonary perfusion pattern in Babesia dogs. / Dissertation (MMedVet (Diagnostic Imaging))--University of Pretoria, 2007. / Companion Animal Clinical Studies / unrestricted

Abnormal carbohydrate metabolism is a commonly encountered feature of malaria in people, and similar derangements have been detected in veterinary patients with canine babesiosis. Glucose, the major metabolic fuel source, is a key resource in critically ill patients as they mount an immunological response to infection and inflammation. The ability of the individual to effectively mobilise, distribute and utilise glucose is a major determinant of morbidity and mortality. Hypoglycaemia has been identified as a life threatening metabolic complication in almost 20% of severely ill dogs suffering from babesiosis due to Babesia rossi infection. Insulin and glucagon are the primary hormones involved in glucose homeostasis. Insulin lowers blood glucose concentration by facilitating cellular uptake and utilisation of glucose. Hyperinsulinaemia as a result of inappropriate insulin secretion may precipitate hypoglycaemia, and has been identif ed as a cause of hypoglycaemia in human and murine malaria. A similar phenomenon may exist in canine babesiosis. This prospective, cross-sectional, observational study, including 94 dogs with naturally acquired virulent babesiosis, sought to investigate and characterise the relationship between blood glucose concentrations and insulin concentrations in cases of canine babesiosis. Pre-treatment jugular blood samples were collected for simultaneous determination of plasma glucose and insulin concentrations. Animals were retrospectively divided into three groups: hypoglycaemic (plasma glucose concentration < 3.3 mmol/L; n=16), normoglycaemic (3.3-5.5 mmol/L; n=62), and hyperglycaemic (> 5.5 mmol/L; n=16). The median plasma insulin concentrations (IQR in parentheses) for the hypoglycaemic, normoglycaemic and hyperglycaemic groups were 10.7 pmol/L (10.7-18.8 pmol/L), 10.7 pmol/L (10.7-29.53 pmol/L; i.e below the detection limit of the assay), and 21.7 pmol/L (10.7-45.74 pmol/L), respectively. Statistical analysis revealed no significant difference in insulin concentration between the three groups. These results suggest that insulin secretion was appropriately suppressed in these dogs. Only two dogs had elevated insulin concentrations, one of which was hypoglycaemic. The median time since last meal (available for 87 dogs) was 24 hours (IQR 2-4 days), constituting a significant period of illness-induced starvation. We conclude that hyperinsulinaemia is not a cause of hypoglycaemia in virulent canine babesiosis. It is speculated that prolonged fasting due to disease-induced anorexia, in addition to increased glucose consumption, depletion of hepatic glycogen stores, and hepatic dysfunction with impaired gluconeogenesis, may play important roles in the pathophysiology of hypoglycaemia in canine babesiosis. / Dissertation (MMedVet)--University of Pretoria, 2010. / Companion Animal Clinical Studies / unrestricted

In an attempt to develop quantitative real-time PCR (qPCR) assays for the detection of equine piroplasms, sequence heterogeneity in the V4 hypervariable region of the 18S ribosomal RNA (rRNA) gene sequences within both Theileria equi and Babesia caballi from South Africa was discovered. A molecular epidemiological survey of the protozoal parasites that cause equine piroplasmosis was therefore carried out using horse and zebra samples from different geographical locations around South Africa. We evaluated the ability of a recently developed T. equi-specific qPCR assay in detecting all T. equi 18S rRNA variants identified in South Africa. We further present the first report on the development and application of a TaqMan minor groove binder (MGB™) qPCR assay, targeting the 18S rRNA gene, for the detection of B. caballi infections in equine blood samples. Despite the ability of the 18S rRNA T. equi- and B. caballi-specific qPCR assays to detect all known 18S rRNA gene sequence variants thus far identified in South Africa, the existence of as yet undetected variants in the field cannot be overlooked. Other qPCR assays targeting alternative genes could be developed which, used in conjunction with the 18S rRNA qPCR assays, may provide better confirmation of test results. A T. equi-specific qPCR assay targeting the equi merozoite antigen gene (ema-1) was recently developed for the detection of T. equi parasites in the midgut of Rhipicephalus (Boophilus) microplus nymphs. This assay was not able to detect T. equi in all South African samples that were confirmed positive by other molecular and serological assays. Sequence characterization of the ema-1 gene from South African isolates revealed the existence of variation in the regions where the qPCR primers and probes had been designed. Based on these observations, a conserved region of the ema-1 gene was selected and targeted in the development of an ema-1-specific TaqMan MGB™ qPCR assay, which was shown to have a higher sensitivity than the previously reported ema-1 qPCR assay. The rhoptry-associated protein (rap-1) gene from South African B. caballi isolates was also characterized following the failure of a B. caballi-specific competitive-inhibition enzyme-linked immunosorbent assay (cELISA) to detect B. caballi antibody in the sera of infected horses from South Africa. The genome walking PCR technique was used to amplify the complete rap-1 gene sequence from two South African B. caballi isolates. Significant heterogeneity in the rap-1 gene sequences and in the predicted amino acid sequences was found. Marked amino acid sequence differences in the carboxy-terminal region, and therefore the probable absence of the monoclonal antibody binding site, explains the failure of the cELISA to detect antibody to B. caballi in sera of infected horses in South Africa. This is the first comprehensive molecular study of the parasites that cause equine piroplasmosis in South Africa. Our results add further to the existing knowledge of piroplasmosis worldwide and will be invaluable in the development of further molecular or serological diagnostic assays. / Thesis (PhD)--University of Pretoria, 2009. / Veterinary Tropical Diseases / unrestricted

Malaria, babesiosis, trypanosomosis, and leishmaniasis are some of the most life-threatening parasites, but the range of drugs to treat them is limited. An effective, safe, and low-cost drug with a large activity spectrum is urgently needed. For this purpose, an aryl amino alcohol derivative called Alsinol was resynthesized, screened in silico, and tested against Plasmodium, Babesia, Trypanosoma, and Leishmania. In silico Alsinol follows the Lipinski and Ghose rules. In vitro it had schizontocidal activity against Plasmodium falciparum and was able to inhibit gametocytogenesis; it was particularly active against late gametocytes. In malaria-infected mice, it showed a dose-dependent activity similar to chloroquine. It demonstrated a similar level of activity to reference compounds against Babesia divergens, and against promastigotes, and amastigotes stages of Leishmania in vitro. It inhibited the in vitro growth of two African animal strains of Trypanosoma but was ineffective in vivo in our experimental conditions. It showed moderate toxicity in J774A1 and Vero cell models. The study demonstrated that Alsinol has a large spectrum of activity and is potentially affordable to produce. Nevertheless, challenges remain in the process of scaling up synthesis, creating a suitable clinical formulation, and determining the safety margin in preclinical models. / Departamento Administrativo de Ciencia, Tecnología e Innovación (COLCIENCIAS) / Revisión por pares

Acute phase proteins (APP) are ideal biomarkers for inflammation due to their stability, relative ease of assay and apparent relation between their concentration and the extent of the insult to tissue. C-reactive protein (CRP) is a positive major APP in dogs and can be used as a predictive marker for risk of disease and to monitor the response to treatment. Increased concentrations in certain diseases are associated with poor outcome. This cross-sectional, observational study of 75 dogs naturally infected with Babesia rossi, a cause of virulent canine babesiosis, was designed to examine the association of CRP concentration at admission and the magnitude of CRP change 24 hours after admission with outcome. Dogs were excluded if there was evidence of concurrent inflammatory diseases at the time of admission, infection with subtypes other than B. rossi, concurrent Ehrlichia canis infections or euthanasia for reasons other than poor prognosis. Diagnosis was confirmed by polymerase chain reaction and reverse line blot. CRP concentrations were determined by an automated human CRP Turbidometric Immunoassay (TIA), previously validated for use in dogs (Bayer CRP TIA, Newbury, UK), on serum samples collected by jugular venipuncture on admission, prior to any therapy, and thereafter daily until discharge or death. There was no significant difference in admission CRP concentration between survivors (n = 57; median = 97.4 mg/l; mean ± SD = 107.5 ± 49.5), and non-survivors (n = 11; median = 101.4 mg/l; mean ± SD = 122.1 ± 64.6) (p = 0.39). After elimination of non-significant predictors, a multiple exact logistic regression model for predicting mortality contained glucose and CRP. Mortality was associated with decreased glucose levels (p = 0.0002) and increased CRP levels (p = 0.045) on admission. Multiple regression analysis failed to show a significant relationship between admission CRP concentration and number of days of hospitalization in the survivors, adjusting for age and sex (p = 0.65). No significance was found in the relationship between the magnitude of change in CRP concentration 24 hours after admission, and the number of days of hospitalization in survivors, (p = 0.34). Using an admission CRP concentration cut-off of 60 mg/l, survival proportions between the two groups were no different (p = 0.34) and when applied to the group of dogs that survived, it was not associated with length of hospitalization (p = 0.25). In corroboration with previous reports glucose was identified as a major prognostic marker for mortality, but additionally the pro-inflammatory marker CRP was identified as a significant co-prognosticator. Copyright / Dissertation (MMedVet)--University of Pretoria, 2009. / Companion Animal Clinical Studies / unrestricted

Com o objetivo de avaliar os equinos alojados no Jóquei Clube de São Paulo, Brasil, quanto a presença de anticorpos contra Theileria equi e Babesia caballi, foram testadas 180 amostras de soro sanguíneo por meio da técnica de C-ELISA (Competitive Enzyme-Linked Immunosorbent Assay), metodologia atualmente recomendada pela OIE (Organização Internacional de Epizootíases) por ter alta sensibilidade e especificidade. A frequência de animais com sorologia positiva para Theileria equi foi de 6,66% (12/180), para Babesia caballi foi de 22,3% (40/180) e para infecção concomitante foi de 6,66% (12/180). Os resultados sorológicos obtidos por este estudo revelam que 35,5% (64/180) dos animais possuem anticorpos contra a babesiose equina sendo que a maioria dos animais acometidos tem dois e três anos de idade e portanto estão há menos tempo no hipódromo. Fatores como a ausência de carrapatos vetores, o uso de terapias babesicidas repetidas e o longo tempo de permanência dos animais no Jóquei após o tratamento, favorecem a diminuição dos títulos de anticorpos sem que ocorra reinfecção. Esses fatores podem justificar o menor número de animais com sorologia positiva para a doença nos cavalos com idade acima de quatro anos. Considerando-se esses resultados sugere-se que os animais sejam avaliados sorologicamente ao ingressarem no Jóquei Clube de São Paulo para que o uso de medicamentos contra a doença seja feito de forma adequada e para que os sinais clínicos compatíveis com babesiose equina em animais sorologicamente negativos sejam melhor avaliados e considerados em diagnósticos diferenciais. / In order to evaluate the presence of antibodies against Theileria equi and Babesia caballi in horses kept at the Jockey Club in São Paulo city, Brazil, a total of 180 samples of blood serum was tested using the Competitive Enzyme-Linked Immunosorbent Assay (C-ELISA test). This methodology has been recommended by the International Organization of Epizooties (IOE) due to its high sensitivity and specificity. The frequency of seropositive animals for Theileria equi, Babesia caballi and for both was 6.66% (12/180), 22.3% (40/180) and 6.66% (12/180), respectively. Serological results showed that 35.5% of the animals (64/180) had antibodies against equine piroplasmosis; they were from two to three years old and were at the Jockey Club for a shorter period of time. Factors such as absence of thick vectors, repeated therapy using babesicidal drugs and the long period of time that the animals stayed in the Jockey Club after treatment favoured the lowering of antibody titers with no reinfection. These factors might be responsible for the fewer number of animals with positive serology for the disease in horses over four years of age. Based on these findings, animals should be serologically evaluated at the time of entrance into the Jockey Club so that the use of drugs against the disease be performed properly and clinical signs suggestive of equine babesiosis in serologically negative animals be better evaluated and considered for differential diagnosis.

Para determinação da ocorrência de transmissão transplacentária da Theileria equi em neonatos eqüinos foram avaliados 50 potros da raça Puro Sangue Lusitano, machos e fêmeas, bem como suas respectivas mães, logo após o parto. Foram colhidas amostras de sangue total, tanto das mães como dos neonatos, entre as primeiras cinco horas pós parto para pesquisa de Theileria equi e Babesia caballi através da técnica de RT-PCR. Utilizou-se o kit de detecção baseado no fluofóro intercalante de DNA SYBERgreen. Um total de 46% das éguas apresentaram resultado positivo para Theileira equi e 54% se mostraram negativas, enquanto que 66% dos potros apresentaram resultados positivos e 34% negativos, sendo que 73,9% dos potros positivos nasceram de mães também positivas. Já para Babesia caballi, 16% das éguas foram positivas e 84% negativas, assim como 2% dos potros foram positivos e 98% negativos. O teste de RT-PCR é bastante sensível e específico, mas pode resultar em falso negativo, apesar de ser eficaz na detecção da Theileria equi e Babesia caballi nos eqüinos. Estes dados permitem concluir que existe a possibilidade de transmissão transplacentária de Theileria equi. / The occurrence of transplacentary transmission of Theileria equi in horses was determined by evaluating 50 young male and female horses of the breed Lusitano Horses as well as their respective mothers. Colts and fillies were evaluated as soon as they were born. Total blood samples were collected from both mother and offspring within the first five hours right after the parturition to analyse Theileria equi and Babesia caballi through the RT-PCR technique. It was used the kit of detection based on DNA SYBERgreen. This study showed us that 46% of the female horses had positive results for Theileira equi and 54% negative results while 66% of the male horses had positive results and 34% of them, negative ones. Moreover, 73.9% of the positive young horses also had their mothers positive. However, for Babesia caballi 16% of the female horses had positive results and 84% negative ones while 2% of the male horses had positive results and 98%, negative ones. The RT-PCR test is very sensitive and specific but it can occur false-negative results although it is efficient in detecting Theileria equi and Babesia caballi in horses. In conclusion, the data show us that there is a possibility of transplacentary transmission of Theileria equi.

Com o objetivo de estudar a fauna parasitária de Cerdocyon thous e Pseudalopex gymnocercus foram estimadas a prevalência, a intensidade média de infecção e abundância de helmintos gastrintestinais e artrópodes nesses hospedeiros. Foram capturados 40 canídeos silvestres na Região Sul do Estado do Rio Grande do Sul, nos municípios de Pedro Osório e Pelotas. Os animais foram capturados usando-se armadilha tipo Live Trap. Logo após a captura, os animais eram sedados, momento em que se coletava sangue e buscava-se coletar artrópodes ectoparasitos mediante exame minucioso. Em seguida os animais eram transportados para o Laboratório de Parasitologia do Departamento de Microbiologia e Parasitologia do Instituto de Biologia da UFPel, onde eram sacrificados usando-se pentobarbital sódico. Após a necropsia, os compartimentos do trato digestório, respiratório e renal foram isolados e examinados na busca de parasitos. O crânio dos animais foi usado para identificação taxonômica dos canídeos, dos quais 45% eram C. thous e 55% P. gymnocercus, podendo-se inferir que ambos canídeos são encontrados habitando a região fisiográfica desse trabalho. A totalidade dos animais (100%) apresentou-se parasitado. Amblyomma aureolatum é o carrapato com maior prevalência em P. gymnocercus (23,7%) e C. thous (61,11%) na região sul do Rio Grande do Sul. Nos nematódeos, os parasitos mais freqüentes foram: Ancylostoma caninum (C. thous 22,22%e P. gymnocercus 45,45%), Molineus felineus (C. thous 5,56% e P. gymnocercus 9,90%), Strongyloides spp. (C. thous 16,67% e P. gymnocercus 22,73%), Trichuris spp (C. thous 11,11% e P. gymnocercus 13,64%), e Capillaria hepática (C. thous 5,56% e P. gymnocercus 13,64%). Nos trematódeos, os parasitos encontrados foram: Alaria alata (C. thous 50,00% e P. gymnocercus 36,36%) e Athesmia heterolecithodes (C. thous 5,56%). Nos cestódeos, os parasitos encontrados foram: Spirometra spp (C. thous 61,11% e P. gymnocercus 54,55%) e Diphillobotriidae (C. thous 77,78% e P. gymnocercus 81,82%). Nos Acanthocephala os parasitos encontrados foram: Centrorhynchus sp. (C. thous 5,56%). Nos protozoários, os 7 parasitos encontrados foram: Babesia spp (P. gymnocercus 13,64%), diagnosticada por exame direto. / With the objective of studying parasitic fauna of Cerdocyon thous and Pseudalopex gymnocercus the prevalence, mean intensity of infection and abundance of gastrintestinal helminths and arthropods were observed in those hosts. 40 wild canids were captured in the South Area of the State of Rio Grande do Sul, in the counties of Pedro Osório and Pelotas. The animals were captured being used trap type “Live Trap”. Therefore after the capture, the animals were anesthesied and in that moment, the blood was collected and the presence or not of ectoparasites was observed. Therefore the animals were transported for the Laboratory of Parasitology, Department of Microbiology and Parasitology, Institute of Biology, UFPel, where they were sacrificed being used sodic pentobarbitol. After this, the portions of the intestinal and respiratory tract and kidney were isolated and examined in the search of parasites. The skull of the animals was used for the taxonomic identification of the hosts. C. thous (45%) and P. gymnocercus (55%) where observed. All hosts (100%) were parazited by some parasite type. Two species of Amblyomma were identified: A. aureolatum and A. tigrinum. Among the nematoda, the most frequent parasites were: Ancylostoma caninum (C. thous 22,22%e P. gymnocercus 45,45%), Molineus felineus (C. thous 5,56% e P. gymnocercus 9,90%), Strongyloides spp. (C. thous 16,67% e P. gymnocercus 22,73%), Trichuris spp (C. thous 11,11% and P. gymnocercus 13,64%), and Capillaria hepática (C. thous 5,56% and P. gymnocercus 13,64%). Among the trematoda, were found Alaria alata (C. thous 50,00% and P. gymnocercus 36,36%) and Athesmia heterolecithodes (C. thous 5,56%). Among the cestoda, the found parasites were: Spirometra spp. and Diphillobotriidae. Acanthocephala the found parasites were: Centrorhynchus sp. and among the protozoa, the found parasites were: Babesia spp (P. gymnocercus 13,64%), diagnosed by direct exam.