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Background Currently, various zoonotic diseases are classified as emerging or reemerging. Because equids have a direct relationship with various vectors, they are possibly more frequently exposed to zoonotic agents than are humans. The undeniable importance of diseases such as human granulocytic anaplasmosis, spotted fever, and leishmaniasis for both public and animal health, as well as the possibility of equids acting as sources, reservoirs, or even sentinels for these pathogens, justifies the detection of their frequency and factors associated with infection in equids from northeastern Brazil. Methods Blood samples were collected from 569 equids (528 horses, 33 donkeys, and 8 mules), 516 from a rural area and 53 from an urban area. Pathogen detection was carried out as follows: Borrelia spp. and Rickettsia spp., serological analysis; Leishmania spp., serological analysis and polymerase chain reaction (PCR); Anaplasma phagocytophilum, PCR. Determination of associated factors was carried out through generalized linear models. Results The frequencies of positivity for the pathogens observed in equids were as follows: Borrelia spp., 13.9% (79/569); Leishmania spp., 3.5% (20/569); Rickettsia spp. 33.4% (190/569). Regarding factors associated with infection, male sex was associated with protection against Borrelia spp.; donkeys and mules were associated with protection against Rickettsia spp., while a younger age was a risk factor. The infection of A. phagocytophilum was not detected in the sampled population. Co-infection was detected in 5.1% (29/569) of the animals. Conclusions Most of the studied pathogenic agents are present in the prospected area, indicating a possible risk for both human and animal health. This demonstrates that equids can be considered important sentinels in the assessment of pathogens with zoonotic potential in the region. Graphical Abstract

Strains of Toxoplasma gondii in Brazil are highly genetically diverse compared to strains from North America and Europe. Dogs are epidemiologically important because they act as sentinels for T. gondii infections in humans and are good indicators of environmental contamination. The aim of this study was to isolate and genetically characterize T. gondii strains from tissues of naturally infected Brazilian dogs. For this study, 21 blood samples were collected from dogs at the Zoonosis Control Centers of Ilheus and Itabuna cities, Bahia, Brazil. The sera were examined for T. gondii antibodies using the indirect hemagglutination test. Brains and hearts of seropositive dogs were bioassayed in mice to isolate and characterize T. gondii parasites by PCR-RFLP using 10 genetic markers (SAG1, newSAG2, SAG3, BTUB, c22-8, c29-2, GRA6, PK1, APICO, and L358). However, T. gondii was isolated from only 4 (57.1%) dogs, designated TgDgBr6, 13, 17, and 21. All strains were virulent, causing clinical changes (rough hair coat, lethargy, and abdominal distention) and the death of all mice within 8-20 days after inoculation. Genetic analysis of these 4 T. gondii isolates revealed 4 distinct genotypes with different clonal lineage combinations (types I, II, and III) and 2 atypical alleles. Using PCR-RFLP with several markers, this study contributes to evaluations of the genetic diversity of strains circulating in Brazil.

The aim of this study was to determine the frequency and factors associated to Babesia caballi, Theileria equi and Trypanosoma evansi in naturally infected equids from the northeast Brazil. Blood samples from 569 equids (528 horses, 8 mules, and 33 donkeys) were collected and tested for the presence of DNA of each of these protozoan parasites by PCR. Generalized linear models were used to evaluate risk factors associated with the infection. The frequency of T. equi infection was 83.5% (475/569) - 84.3% in horses, and 73.2% in donkeys and mules. The results of the final model indicated that age (senior group) and animal species (mule and donkey group) were protective factors against this pathogen. The frequency of B. caballi infection was 24.3% (138/569) - 23.5% in horses and 34.1% in donkeys and mules. Age (adult and senior group) was considered a protective factor against B. caballi infection whereas animal species (donkey and mule group) were considered a risk factor for the infection. Trypanosoma evansi infection was not detected in any of animals. Our results suggest that equids from the area studied may be infected earlier in life with the etiological agents of equine piroplasmosis and become asymptomatic carriers. Resumo Este estudo teve como objetivos conhecer a frequência e os fatores associados à infecção por Babesia caballi, Theileria equi e Trypanosoma evansi em equinos naturalmente infectados do nordeste do Brasil. Amostras de sangue de 569 equídeos (528 equinos, 8 muares e 33 asininos) foram coletadas e testadas para a presença do DNA destes parasitos através da PCR. Modelos lineares generalizados foram utilizados na avaliação dos fatores associados às infecções. A frequência de infecção por T. equi foi de 83,5% (475/569) -84,3% (445/528) em eqüinos e 73,2% (30/41) em asininos e muares. Os resultados do modelo final indicam idade (sênior) e espécie (muar e asinina) como possíveis fatores de proteção para este patógeno. A frequência de infecção por B. caballi foi de 24,3% (138/569) - 23,5% (124/528) em eqüinos e 34,1% (14/41) em asininos e muares. As faixas etárias (adulto e sênior) foram identificadas como possíveis fatores de proteção, e a espécie (asinina e muar) como risco para ocorrência de infecção por B. caballi. Infecções por Trypanosoma evansi não foram detectadas. Estes resultados indicam que os equídeos na região estudada se infectam precocemente com agentes da piroplasmose equina tornando-se portadores assintomáticos.

Leishmaniosis is a zoonosis caused by protozoa of the genus Leishmania. American cutaneous leishmaniosis (ACL) is mainly caused by the species L. amazonensis and L. braziliensis, and American visceral leishmaniosis (AVL) is caused by L. infantum chagasi. In addition to their proven roles as reservoirs of AVL, dogs are also suspected by researchers to be reservoirs of ACL due to reports of this infection in domestic environments and of infected dogs in endemic areas. The aim of this study was to detect Leishmania sp. infection in dogs from Vila Operária, Buerarema, Bahia, using parasitological tests, indirect immunofluorescent assay (IFA) and polymerase chain reaction (PCR). Furthermore, this study also aimed to identify risk factors associated with illness in dogs in this locality by conducting an epidemiological survey. For this purpose, 292 dogs were clinically evaluated for the presence of skin lesions, and the dogs that showed these changes were submitted to scarification injury to enable preparation of slides for microscopic study of amastigotes. Subsequently, the dogs underwent blood sampling for serological (IFA) and molecular (PCR) tests. Additionally, the owners of the dogs answered an epidemiological questionnaire to facilitate the identification of risk factors for exposure of dogs to pathogens of ACL. Of the 292 dogs studied, 13 (4.5%) had lesions suggestive of ACL, but with a negative parasitological examination and 147 (50.3%) were seropositive according to the IFA. Of the 273 dogs studied using PCR test, 10 (3.66%) were positive for L. braziliensis, and all samples were negative for L. infantum chagasi. Wastelands in the peridomicile and the presence of light in the household were risk factors associated with ACL. The results show that Vila Operária has asymptomatic dogs with ACL and that the detection sensitivity of the IFA was higher than that of PCR for the infected dogs.

Direct diagnoses were made by using - blood smears and nested PCR (nPCR) tests on 309 blood samples from crossbred dairy cattle in the municipality of Ibicaraí, Bahia. From diagnostic blood smear slides, the observed parasitic frequencies were 31.1% for Anaplasma marginale and 20.4% for Babesia sp. From nPCR diagnoses, they were 63% for A. marginale, 34% for Babesia bigemina and 20.4% for Babesia bovis. There were significant differences (P

The aim of this study was to characterize the role of quails (Coturnix coturnix japonica) as intermediate hosts for Neospora caninum. Fifty-eight 20-day old quails were individually identified with numbered rings and kept in cages adequate for the species. The birds were fed commercial feed and distilled water ad libitum. They were weighed daily during the first month and every seven days from then on. The birds were randomly distributed into 3 groups; 40 quails (group A) and 8 quails (group B) received 3.5 × 106 and 5 × 106N. caninum tachyzoites, respectively, and 10 quails (group C) received placebo. Four quails from group A and one from group C had their blood collected and were euthanized on the 1st, 3rd, 5th, 7th, 14th, 21th, 30th, 60th, 120th day after infection (DAI), and 4 quails from group B were euthanized on days 60th and 120th DAI. Following euthanasia, the birds were submitted to necropsy, the organs were weighed and fragments were collected for histopathology, immunohistochemistry (IHC) and PCR. On the 60th DAI, two dogs were fed tissue obtained from group A quails, and one dog was fed quail tissues from group B. The dogs’ blood was collected weekly for serology, and their feces were collected daily for 33 days for microscopy and molecular identification of oocysts. Student's t-test was used to compare the weights of the collected organs and the quail and cloacal temperature. No quail presented any clinical signs or died. Splenomegaly and hepatomegaly were the primary necropsy findings during the first week of infection (p

Strains of Toxoplasma gondii in Brazil are highly genetically diverse compared to strains from North America and Europe. Dogs are epidemiologically important because they act as sentinels for T. gondii infections in humans and are good indicators of environmental contamination. The aim of this study was to isolate and genetically characterize T. gondii strains from tissues of naturally infected Brazilian dogs. For this study, 21 blood samples were collected from dogs at the Zoonosis Control Centers of Ilhéus and Itabuna cities, Bahia, Brazil. The sera were examined for T. gondii antibodies using the indirect hemagglutination test. Brains and hearts of seropositive dogs were bioassayed in mice to isolate and characterize T. gondii parasites by PCR-RFLP using 10 genetic markers (SAG1, newSAG2, SAG3, BTUB, c22-8, c29-2, GRA6, PK1, APICO, and L358). However, T. gondii was isolated from only 4 (57.1%) dogs, designated TgDgBr6, 13, 17, and 21. All strains were virulent, causing clinical changes (rough hair coat, lethargy, and abdominal distention) and the death of all mice within 8–20 days after inoculation. Genetic analysis of these 4 T. gondii isolates revealed 4 distinct genotypes with different clonal lineage combinations (types I, II, and III) and 2 atypical alleles. Using PCR-RFLP with several markers, this study contributes to evaluations of the genetic diversity of strains circulating in Brazil.

This study genetically Toxoplasma gondii isolates obtained from pigs intended for human consumption in northeastern Brazil; multilocus PCR-RFLP and sequencing techniques were utilized. Bioassays were conducted using the brain and tongue of 20 pig heads purchased at butcher shops in the city of Ilheus, Bahia, Brazil. Overall, 11 T. gondii isolates designated TgPgBr06-16 were identified. Application of multilocus PCR-RFLP with seven molecular markers (SAG1, SAG2, SAG3, BTUB, C22-8, PK1 and Apico) identified six different genotypes. Isolates TgPgBr 06, 08, 11, 12, 14 and 15 were indistinguishable by this technique, forming a single genotype; the remaining isolates were characterized as distinct genotypes. However, when five genetic markers (SAG1, SAG2, SAG3, BTUB and c22-8) were employed in multilocus PCR-sequencing, all eleven strains of T. gondii were shown to be different. All isolates differed from Type I, II and III clonal genotypes using both genotyping techniques. These results demonstrate that the multilocus PCR-RFLP assay underestimated the true diversity of the T. gondii population in this study. Thus, DNA sequencing is the preferred technique to infer the genetic diversity and population structure of T. gondii strains from Brazil. Moreover, it is necessary to develop new molecular markers to group and characterize atypical T. gondii isolates from South America.

Background : Canine Visceral Leishmaniasis is a zoonosis affecting dogs worldwide. Its epidemiological importance is observed in Brazil, wherein the largest number of cases originates in the Northeast Region of the country. The disease is caused by the etiologic agent Leishmania chagasi (= infantum ) and transmitted by an invertebrate form of sand fly of the genus Lutzomia . Domestic dogs are one of the main reservoirs. The aim of this study was to use molecular analysis to diagnose dogs naturally infected with Leishmania spp. in the city of Jequie, State of Bahia, Brazil, and to describe the clinical signs, as well as the hematological and biochemical profiles associated with these cases. Materials, Methods & Results : In the present study, 198 dogs underwent physical examination and had blood samples collected for hematological, biochemical and PCR tests for Leishmania infantum . Two primers have been used for the molecular diagnostic technique (PCR): first, the ITS-1 specific to Leishmania species followed by the PCR-RFVL to identify the genus; and second, the primer pair RV1/RV2 specific to the Leishmania infantum species in all the samplesAmong the 198 samples collected, four animals tested positive for the Leishmania infantum via PCR, two of which were symptomatic and two asymptomatic. Among the symptomatic animals, animal one presented with diffuse alopecia, ulcerated lesions on the tip of the ears, ophthalmopathy, onychogryphosis, cachexia, anemia and neutrophilic leukocytosis, and animal two presented with alopecia, pustules, crusting, diffusely-spread erythema, anemia, hyperproteinemia, thrombocytopenia and azotemia. Among the two asymptomatic dogs, one animal had anemia, hyperproteinemia, thrombocytopenia, leukocytosis with neutrophilia, and azotemia; the other animal’s laboratory findings revealed hyperproteinemia and leukocytosis with neutrophilia. Discussion : Although 48 animals presented clinical signs, as well as hematological and biochemical alterations commonly reported in the available literature on Leishmaniasis, only two tested positive by PCR. This implies that a positive diagnosis for this pathology should not be given only based on nonspecific clinical and laboratory data. On the other hand, two animals positive via PCR were asymptomatic, and could act as silent disseminators of the parasite in the region. Since the region is considered endemic for the disease, many dogs may be in the chronic phase, with low parasitemia. The fact that blood with low parasitemia was examined may have influenced the estimate of the ocurrence, as it is common knowledge that in such cases the PCR can deliver a false-negative result due the low amount of DNA for amplification. The ideal tissue should be obtained from the spleen, liver, lymph nodes or via bone marrow puncture. However, it was not possible to collect this kind of tissue due to the need for general anesthesia, which is a limiting factor when the study is conducted with domiciliated animals. Clinical signs found in positive animals involve different systems, due to the multisystemic nature of the disease, and evaluation for differential diagnosis is essential to rule out other pathologies that lead to similar changes, such as systemic lupus erythematosus, ehrlichiosis, and babesiosis, among others. Some of the hematologic changes found in positive animals included: anemia, hyperproteinemia, leukocytosis; all of which are respectively correlated with spinal cord dysfunction, splenic sequestration and hyperglobulinemia due to the intense immune response. We concluded that the PCR enabled the identification of canine visceral leishmaniasis cases in the city of Jequie. However, our study did not identify a relationship between the molecular positivity of dogs to Leishmania infantum and the clinical signs and the hematologic and biochemical analysis of samples from suspected cases. Keywords: zoonosis, molecular diagnosis, symptomatology, DNA sequence.

Chagas disease, caused by the flagellate protozoan Trypanosoma cruzi, is an anthropozoonosis of great importance for public health. Several species of mammals are reservoirs for this parasite, including dogs. The objective of this work was to verify the natural infection by T. cruzi in the population of dogs of the municipality of Ituberá, Bahia. A total of 392 domiciled dogs from all districts of the city were evaluated; five milliliters of blood was collected from the dogs for molecular diagnosis. T. cruzi DNA was amplified through the polymerase chain reaction (PCR); the primers P35 and P36, which amplify a fragment of 330 bp, were used. The PCR products were subjected to 2% agarose gel electrophoresis containing Sybr (Invitrogen). Of the 392 dogs evaluated, only 2 (0.51%) animals, one male and one female, tested positive for T. cruzi. This study concluded that there are dogs naturally infected by T. cruzi in the municipality of Ituberá-Bahia and that this finding is an alert to veterinarians, health professionals, and local health authorities that their own dogs can act as reservoirs of the disease. A Doença de Chagas, causada pelo protozoário flagelado Trypanosoma cruzi, é uma antropozoonose de grande importância para a saúde pública. Diversas espécies de mamíferos são reservatórios do parasita, incluindo o cão. O objetivo deste trabalho foi verificar a infecção natural por T. cruzi na população de cães do município de Ituberá, Bahia. Foram avaliados 392 cães domiciliados, em todos os bairros do município, dos quais foram coletados 5mL de sangue para realização do diagnóstico molecular. A amplificação do DNA de T. cruzi foi através da Reação em Cadeia da Polimerase (PCR), com os primers P35 e P36, que amplificam um fragmento de 330 pb. Os produtos das PCRs foram submetidos à eletroforese em gel de agarose a 2% contendo Sybr (Invitrogen®). Dos 392 cães avaliados, apenas 2 (0,51%) animais, um macho e uma fêmea, foram positivos no diagnóstico molecular de T. cruzi. Conclui-se com esse estudo que há cães naturalmente infectados pelo T. cruzi no município de Ituberá-Bahia e que este achado constitui um alerta aos veterinários, profissionais da saúde e autoridades sanitárias locais, cujos cães podem atuar como reservatórios da doença.

Toxoplasmosis, leishmaniasis, and ehrlichiosis are zoonoses that have cosmopolitan distribution and cause important clinical changes in dogs and humans. Dogs are important in the epidemiology and transmission of Leishmania infantum and Ehrlichia canis and serve as indicators of environmental contamination by the transmission of Toxoplasma gondii. The aim of this study was to detect antibodies against T. gondii, Leishmania spp., and E. canis in dogs from Bahia and identify the risk factors associated with infections. Blood samples were collected from 353 dogs from several municipalities of Bahia and the sera were tested using reaction of indirect immunofluorescence (RIFI) for T. gondii and Leishmania spp. and enzyme-linked immunosorbent assay (ELISA) for E. canis. The data were tabulated and analyzed using EPI-INFO 7.1.5 program. Of 353 samples analyzed, 144 (40.8%) were positive for T. gondii (antibody titer 16-4,096) and 92 (26.1%) were seropositive for Leishmania spp. (antibody titer 40-160). The seropositivity for E. canis was the highest as compared to that of the other agents. Furthermore, 184 (52.1%) samples were positive for antibodies against E. canis. Sixteen (4.5%), 71 (20.1%), and 25 (7.1%) samples were co-infected with T. gondii and Leishmania spp., T. gondii and E. canis, and E. canis and Leishmania spp., respectively, while 20 (5.7%) dogs presented co-seropositivity for all three etiological agents. Risk factors such as age, sex, habitat (stray/not stray), and region of dog’s origin were analyzed; age ( ? 1 year) was significantly associated with T. gondii (p = 0.03) and E. canis (p = 0.02) infection and stray animals were more exposed to T. gondii (p = 0.03) and Leishmania spp. (p = 0.01) infection. The results confirmed the heterogeneous distribution of the three etiological agents in dogs from Bahia and identified animals with co-infections.

The objective of the present article was an epidemio- logical and molecular study of Ehrlichia canis in dogs of Ilheus and Itabuna in Bahia, as well as an evaluation of associated risk factors. Blood samples were collected from 153 dogs and DNA was extracted and analyzed by the nested-polymerase chain reaction, us- ing one pair of primers to detect Ehrlichia bacteria and another pair to detect the presence of E. canis. Of the 153 animals, 12 (7.8%) were polymerase chain reaction-positive for E. canis, indicating the presence of the parasite in dogs of the Ilheus-Itabuna microregion. The associated risk factors were exposure to tick-infested habitats and the fact that the dogs lived in the countryside.

In Brazil, canine hepatozoonosis is a tick-borne subclinical hemoparasitosis caused by a protozoa Hepatozoon canis and is highly prevalent in dogs in rural areas. An epizootiological study was conducted to investigate the prevalence of H. canis in the canine population of Ituberá, Bahia, and to analyze any associated risk factors. Blood samples were collected from 380 dogs and determined the presence of the protozoan by performing capillary blood smear and polymerase chain reaction (PCR). Epizootiological data were collected by asking dog owners to answer a structured questionnaire. H. canis gamonts were not detected in the blood smears. However, PCR detected H. canis in 163/380 (42.9%) dogs examined. Physical examination and anamnesis indicated 105 (64.4%) positive asymptomatic dogs. Hematological alterations were observed in 115 (70.5%) infected dogs. No clinical, hematological, or epizootiological variable was found to be significantly associated to the infection. In conclusion, the high prevalence of H. canis infection in local dogs may be because of the peri-urban features of this municipality. Moreover, to the best of our knowledge, this study the first study to report H. canis infection in the State of Bahia.

Leishmaniasis is a disease caused by protozoa of the genus Leishmania. Two distinct forms are recognized: visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL). In the Americas, the causative agent of VL is L. infantum chagasi, whereas L. braziliensis is principally responsible for CL. Domestic dogs constitute the main source of VL in urban environments, and have also been implicated in CL epidemiology. We carried out molecular and serological surveys to detect Leishmania infection in dogs from the municipality of Ituberá in Bahia, Brazil. Furthermore, we identified risk factors associated with illness in dogs from this locality. Blood samples were collected from 399 dogs and tested using an indirect immunofluorescence assay (IFA) and polymerase chain reaction (PCR) to detect Leishmania spp antibodies and L. infantum chagasi and L. braziliensis DNA, respectively. Dogs were clinically evaluated and tissue samples from those exhibiting skin lesions were examined for parasites. In addition, the dog owners completed an epidemiological questionnaire to identify factors associated with infection. Skin lesions consistent with CL were found on 37 (9.3%) of the evaluated animals, but parasitological examination was negative for all samples. The IFA returned positive results for 60 (15%) dogs. PCR identified DNA from L. braziliensis in 86 (21.6%) animals, where as all samples proved negative for L. infantum chagasi. The 134 dogs (33.6%) testing positive using IFA and/ or PCR were considered infected, and of these, only 13 demonstrated skin lesions. Animals from rural areas were 3.39-times more likely to be infected compared to those in urban environments.

Leishmaniasis is an endemic disease present in 98 countries. In Brazil, the northeast region accounts for approximately half of the cases in humans, and has experienced an increased number of positive cases in dogs. In this study, we investigated the epidemiology of canine leishmaniasis in the city of Ilheus, Bahia, using serological and molecular techniques and evaluated the possible environmental risk factors and associated clinical signs. Blood samples were collected from 560 dogs in urban and peri-urban areas in Ilheus, northeastern Brazil. Genomic DNA was extracted from the selected animals and subjected to molecular analysis using Leishmania species-specific primers and diagnosis of Trypanosoma cruzi. A total of 54.72% of dogs were positive for Leishmania braziliensis, and animals positive for both Leishmania infantum and T. cruzi were not identified. Hematologic variables were not statistically associated with cases of L. braziliensis. However, the positive animal group showed lower red blood cell and platelet counts and higher levels of urea and serum creatinine. Few dogs presented clinical signs compatible with the presence of Leishmania. Age of more than 2 years and specific hair colors were associated with positive results for L. braziliensis. The geoclimatic characteristics of the region may improve parasite survival, reproduction, and vectors. This may explain the higher rate of dogs identified as positive in this study.

Ehrlichiosis is a zoonotic disease that is caused by bacteria of the genus Ehrlichia. The aims of this study were to detect the presence of Ehrlichia spp. in the blood of dogs in Ituberá, Bahia, and to compare the sensitivities and specificities of blood smear, serological, and molecular examinations. Furthermore, this study identified factors associated with exposure to the agent in dogs in this locality. Blood samples were collected from 379 dogs and submitted for indirect immunofluorescent assay and polymerase chain reaction testing for the detection of Ehrlichia spp. antibodies and DNA, respectively. Additionally, a peripheral blood smear was obtained from the ear tip for parasite identification. Of the 379 animals, 12.4%, 32.7%, and 25.6% were identified as positive on the blood smear, serological, and molecular tests, respectively. The dogs positive in one of the three techniques were considered exposed (46.9%). Younger dogs and rural habitat were protective factors and presence of ticks and contact with other dogs were the risk factors associated with exposure to the agent. It was concluded that dogs of Ituberá have high positivity for Ehrlichia spp. and that the diagnostic methods used for detection are complementary. Erliquiose é uma doença zoonótica causada por bactérias do gênero Ehrlichia. O objetivo desse estudo foi detectar a presença de Ehrlichia spp. no sangue de cães em Ituberá-BA, e comparar as sensibilidades e especificidades do esfregaço sanguíneo, e testes sorológico e molecular. Além disso, esse estudo identificou fatores associados com a exposição ao agente em cães desta localidade. Amostras de sangue foram coletadas de 379 cães e submetidas à Reação de Imunofluorescência Indireta e Reação em Cadeia de Polimerase para detecção de anticorpos e DNA de Ehrlichia spp., respectivamente. Adicionalmente, sangue periférico de ponta de orelha foi coletado para identificação do parasita. Dos 379 animais, 12,4%, 32,7% e 25,6% foram identificados como positivos no esfregaço sanguíneo, teste sorológico e molecular, respectivamente. Cães positivos em uma das três técnicas foram considerados expostos (46,9%). Cães mais novos e hábitat rural foram fatores de proteção e presença de carrapatos e contato com outros cães foram os fatores de risco associados à exposição ao agente. Foi concluído que, os cães do município de Ituberá têm alta positividade para Ehrlichia spp. e que os diferentes métodos diagnósticos utilizados para sua detecção são complementares.

Recent studies have demonstrated that strains of Toxoplasma gondii in Brazil are frequently different from those detected in other countries, thus making an accurate phylogenetic analysis difficult. The aim of this study was to genetically characterize T. gondii samples from sheep raised in southern Bahia and intended for human consumption, by means of PCR–RFLP and sequencing techniques. Experimental samples were obtained from 200 sheep brains purchased at butcher's shops in Itabuna, Bahia, Brazil. In total, three samples (#54, #124 and #127) were T. gondii-positive. The application of multilocus PCR–RFLP using ten molecular markers (SAG1, SAG2, SAG3, BTUB, c22-8, PK1, GRA6, L358, c-29-2 and Apico) revealed a single genotype common to all samples of this study, which differed from any other published T. gondii genotypes. An atypical allele was detected in the L358 genetic marker; this has not previously been shown in any other South American T. gondii isolates. Phylogenetic analysis on the sequences from multilocus PCR sequencing revealed that these three samples were classified into the same lineage. Extensive indel regions were detected in the Apico genetic marker. Together, our findings revealed a new Brazilian T. gondii genotype. Further research should be conducted to enrich the database of Brazilian T. gondii genotypes from different regions. This will make it possible to understand the phylogenetic relationship between isolates.

In order to verify the Trypanosoma cruzi infection in domestic domiciled dogs in a rural endemic area from the south region of the State of Bahia, Polymerase Chain Reaction (PCR) were performed using S35 and S36 primers in 272 dogs living in the district of Vila Operaria, in the municipality of Buerarema. All animals were clinically evaluated; 2.5 mL of blood were collected through venipuncture for the performance of molecular tests. None of these animals showed clinical signs of the illness and only two were identified with the DNA parasite. This result is the first report of natural infection by T. cruzi in domestic dogs in southern Bahia. Com o objetivo de verificar a infecção porTrypanosoma cruzi em cães domésticos domiciliados em área rural e endêmica do sul da Bahia, foi realizada a Reação em Cadeia da Polimerase (PCR), utilizando-se os iniciadores S35 e S36 em 272 cães domiciliados no distrito da Vila Operária, cidade de Buerarema. Todos os animais foram avaliados clinicamente e, posteriormente, foram coletados 2,5 mL de sangue por punção venosa para realização do diagnóstico molecular. Nenhum dos animais apresentou manifestação clínica da doença e, em apenas dois foram identificados DNA do parasito. Esse resultado é o primeiro relato de infecção natural por T. cruzi em cães domésticos no sul baiano.

This study aimed to compare the sensitivity of five diagnostic methods commonly used for the detection of Toxoplasma gondii in tissues of naturally infected pigs. We purchased 20 heads of pigs in butcher shops in the city of Ilheus, Bahia. Brain and tongue fragments were taken from each animal for the performance of PCR against T. gondii. The rest of these two tissues were processed and inoculated into three mice. These rodents were observed for 42 days and euthanized. We prepared slides with brain and lungs of each mouse for the visualization of T. gondii. From the tissues of mice, we carried out polymerase chain reaction (PCR), histopathology, and immunohistochemistry in an attempt to identify the parasite. The PCR direct from the tissue of pigs showed 10% (2/20) of positive samples, all from the brain. PCR in tissue from mice found that 55% (11/20) of pigs were positive: 55% (11/20) and 45% (9/20) for brains and tongues, respectively. Mice were inoculated with material obtained from the samples and examined by various methods for resulting Toxoplasma infection (bioassay). Cyst detection in bioassay mice identified 25% (5/20) and immunohistochemistry 30% (6/20) of the samples pigs as positive for T. gondii. Histopathology of mice tissue could not detect parasite; only suggestive pathological changes such as inflammation with foci of necrosis were seen. The results indicated PCR of mice tissue as the most sensitive among those tested.

We used PCR to test various protocols and define a technique for DNA extraction directly from chicken-shed stool samples for the identification of Eimeria species that parasitize birds. It was possible to extract and amplify DNA of seven Eimeria species from field stool samples, using both protocols tested; extractions made with phenol/chloroform protocols gave the best results. The primers were specific and sensitive, allowing amplification of samples containing as few as 20 oocysts, both in individual and in a multiplex PCR. Individualized PCR with the phenol/chloroform DNA extraction protocol detected a larger number of Eimeria species. Molecular diagnosis was found to be practical and precise, and can be used for monitoring and epidemiological studies of Eimeria. Made available in DSpace on 2018-01-26T23:36:59Z (GMT). No. of bitstreams: 1 APIMoleculardiagnosis.pdf: 661266 bytes, checksum: 8327ce0f55733a20b1b1bc705ecdbde1 (MD5) Previous issue date: 2011-12-02

The objective of this study was to identify and characterize species of Eimeria in broiler chickens using traditional morphological and pathological plus molecular (DNA amplification) diagnostic methodologies. Using a combination of those techniques it was possible to identify the presence of multiple circulating species in the flock as well as higher frequencies for some of them, especially Eimeria praecox and Eimeria maxima, which were identified in 100% of the flocks. The frequencies of the other species were Eimeria mitis and Eimeria necatrix (93.3%), Eimeria tenella (76,7%), Eimeria acervulina (56.7%) and Eimeria brunetti (16.7%). However using the lesion score, the most common species were E. maxima (46.7%), E. acervulina (30%), E. tenella (23.3%), and E. necatrix (10%). E. brunetti and E. praecox were not identified by using lesion score. DNA amplification had detection sensitivity for Eimeria species in the field samples of at least 20 oocysts. The implementation of DNA amplification as a routine diagnostic technique in aviaries can assist Eimeria population.

The aim of this work was to study the clinical disorders and risk factors of canine ehrlichiosis in Ilhéus and Itabuna, Bahia, and compare different diagnostic methods. Blood samples were collected from 200 dogs. Each dog was clinically examined. A questionnaire was used to evaluate the risk factors. The blood samples were analyzed using the Dot-ELISA test; hematometry, platelet counts and searches for morulae on blood smears were performed. Nested PCR was carried out on 50 serologically positive samples and 50 negative samples. Three positive PCRs were sequenced. Thirty-six percent were serologically positivity and 5.5% from blood smears. The animals were anemic and thrombocytopenic. Presence of ticks and living in areas on the urban periphery were considered to be risk factors (p < 0.05). Nested PCR identified 11 positive dogs of which nine were serologically positive and two were negative. The DNA sequencing was consistent with the presence of Ehrlichia canis. Objetivou-se com este trabalho estudar as alterações clínicas, fatores de risco da ehrlichiose canina nos municípios de Ilhéus e Itabuna, Bahia, e comparar diferentes métodos de diagnóstico. Amostras de sangue foram coletadas de 200 cães e cada animal foi examinado clinicamente. Foi preenchido um questionário para avaliar os fatores de risco. As amostras de sangue foram analisadas pelo teste Dot-ELISA e foram realizadas hematimetria, contagem de plaquetas e procura de mórulas em esfregaço de sangue. Nested-PCR foi realizada em 50 amostras positivas e 50 negativas na sorologia. Três amostras PCRs positivas foram seqüenciadas. Foi encontrado 36,0% de positividade na sorologia e 5,5% nos esfregaços sanguíneos. Os animais apresentavam anemia e trombocitopenia. Ter carrapatos e residir em áreas suburbanas foram considerados fatores de risco (p < 0,05). A Nested-PCR identificou 11 cães positivos, sendo 9 com sorologia positiva e 2 negativos. O sequenciamento de DNA foi compatível com a presença de Ehrlichia canis.

In Brazil, Leishmania infantum mainly affects humans and dogs. The state of Bahia presents many dogs that are positive for this parasite. Despite the importance of epidemiology in this region, there are still very few studies that have assessed the genetic characteristics of L. infantum. The aim of this study is to investigate the genetic variability of L. infantum isolated identified in naturally infected dogs, in order to verify occurrence of subpopulation of this parasite in the different biomes existing in the state of Bahia. Thirty-two samples of L. infantum were analyzed, which were obtained isolated in dogs from the Mata Atlântica (rainforest), Caatinga (semi-arid scrub forest), and Cerrado (a vast tropical savannah eco-region) Bahia municipalities’ biomes. All animals presented with clinical changes suggestive of Leishmania spp. and they exhibited positive reactions to serological tests. kDNA analysis with RFLP markers revealed the presence of genetic variability and gene flow in subpopulations of L. infantum; samples from the Mata Atlântica areas were genetically more similar to those from the areas of Caatinga and they were less likely to resemble those of the Cerrado. This data may be used to investigate the dissemination of parasite in the canine population of state of Bahia. Resumo No Brasil a Leishmania infantum afeta principalmente o homem e os cães. O estado da Bahia apresenta elevado número de cães positivos por este parasito. Apesar da importância epidemiologia para a região, ainda há poucos estudos que avaliam as características genéticas de L. infantum. Objetivou-se com este estudo investigar a variabilidade genética de cepas de L. infantum identificadas em cães naturalmente infectados, a fim de verificar a ocorrência de sobpopulações do parasito nos diferentes biomas existentes no estado da Bahia. Foram analisadas 32 amostras de L. infantum isoladas em cães de municípios baianos distribuídos nos biomas Mata Atlântica, Caatinga e Cerrado. Todos os animais apresentavam alterações clínicas sugestivas de Leishmania spp. e reação positiva em exames sorológicos. A análise do kDNA com marcadores RFLP revelaram a presença de variabilidade genética e fluxo gênico nas subpopulações de L. infantum sendo que as amostras das áreas de Mata Atlântica foram geneticamente mais semelhantes as das áreas de Caatinga e foram mais distantes daquelas oriundas do Cerrado. Estas informações podem auxiliar em investigações de dispersão do parasito na população canino do Estado da Bahia.