Occurrence of anti-Neospora caninum and anti-Toxoplasma gondii IgG antibodies in goats and sheep in western Maranhão, Brazil

A neosporose e a toxoplasmose são doenças parasitárias que podem causar problemas reprodutivos em caprinos e ovinos. O objetivo deste estudo foi determinar a ocorrência de anticorpos IgG anti-Neospora caninum e anti-Toxoplasma gondii em caprinos e ovinos dos municípios de Amarante do Maranhão e Buritirana, microrregião de Imperatriz, Oeste maranhense, Nordeste do Brasil, bem como avaliar fatores associados à infecção por esses agentes etiológicos. Amostras de sangue de 110 animais (46 caprinos e 64 ovinos), provenientes de cinco propriedades, foram coletadas, e a reação de imunofluorescência indireta utilizada para o diagnóstico sorológico. Das 46 amostras de caprinos, 17,39% (n = 8) apresentaram anticorpos anti-N. caninum e 4,35% (n = 2) anti-T. gondii, enquanto das 64 amostras de ovinos, 4,69% (n = 3) e 18,75% (n = 12) apresentaram anticorpos anti-N. caninum e anti-T. gondii, respectivamente. Não houve diferença significativa, considerando-se a presença de gato e/ou cão na propriedade e assistência veterinária para ambos os agentes estudados. Entretanto, suplementação alimentar e presença de animais com problemas reprodutivos diferiram significativamente (p < 0,05) em ovinos e caprinos, respectivamente. Os resultados do presente estudo demonstraram que caprinos e ovinos, da região Oeste do Maranhão são expostos aos coccídios N. caninum e T. gondii. Essa é a primeira evidência desses agentes em pequenos ruminantes nessa região.

Occurrence of anti-Toxoplasma gondii and anti-Neospora caninum antibodies in cats with outdoor access in São Luís, Maranhão, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Survey for natural Neospora caninum infection in wild and captive birds

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Occurrence of anti-Neospora caninum antibodies in Brazilian cervids kept in captivity

Neospora caninum is a coccidian parasite that causes disease in captive and domesticated animals and has been found in wild animals such as cervids. Sera from 150 cervids of the genus Mazama, were collected from 31 captive herds and 16 zoos from different Brazilian regions and analyzed by indirect fluorescent antibody test for anti-N. caninum antibodies. Positive reactions were found in 42% (63) of the samples and the titers varied from 50 to 51,200. of the 86 cervids from the captive herds, 38 (44.2%) had anti N. caninum antibodies and of the 64 samples from the zoo, 25 (39.1%) were positive. No significant difference (p > 0.05) was found for the occurrence values observed between the animals from captive herds and zoos as well as within the values documented for each one of the species analyzed. Therefore, the results indicate that the agent is prevalent from cervids in captivity in Brazil. (c) 2005 Elsevier B.V. All rights reserved.

Environmental effect on the occurrence of anti-Neospora caninum antibodies in pampas-deer (Ozotoceros bezoarticus)

Sera obtained from pampas-deer (Ozotoceros bezoarticus) captured in two different Brazilian environments were analyzed for the presence of anti-Neospora caninum antibodies by the indirect fluorescent antibody test (IFAT). Samples were collected from 23 animals from a savanna area in the National Park of Emas, in the state of Goias, Brazil. This area is surrounded by cultivated lands and allows very little contact between wild and domestic animals. Another batch of samples was collected from 16 animals from the Pantanal region, in the state of Mato Grosso, Brazil. This area is a flood plain where domestic animals have intensive contact with cervids. The 39 samples were analyzed (IFAT >= 1:50), and the values for the occurrences found in the animals from each region were compared by the test for comparison of two proportions. of the 39 cervids examined, 38.46% (15) had anti-N. caninum antibodies. Three (13%) of the 23 samples from the National Park of Emas. and 12 (75%) of the 16 samples from the Pantanal were positive, with significant differences between regions (p < 0.001). These results suggested that the presence of domestic animals, mainly dogs and cattle, may be responsible for the greater occurrence of N. caninum in the Pantanal cervids.Thus, as a recommendation of the Conservation Units that care for the pampas-deer, attention should be taken to carefully monitor the flow of diseases between the domestic animals and this species. (c) 2005 Elsevier B.V. All rights reserved.

Ocorrência de anticorpos anti-Neospora caninum em cães da microrregião da Serra de Botucatu, Estado de São Paulo, Brasil

Neosporose é uma enfermidade parasitária causada pelo protozoário Neospora caninum reconhecido como importante causa de abortamento bovino e neuropatia canina. Considerando o isolamento de N. caninum e a sorologia freqüente em bovinos em nossa região, os objetivos do presente trabalho foram avaliar a ocorrência de anticorpos anti-N. caninum em cães da Microrregião da Serra de Botucatu, Estado de SãoPaulo, e sua associação ao sexo, idade e procedência quanto à zona urbana (exclusivamente cidade), rural (somente chácaras e sítios) e peri-urbana (acesso à zona urbana e rural) dos cães estudados. Foram analisados 963 cães, com ou sem raça definida, de ambos os sexos e diferentes idades, sem apresentação de qualquer sintomatologia clínica. Os animais foram selecionados aleatoriamente durante a campanha de vacinação anti-rábica da microrregião da Serra de Botucatu, no período de maio a setembro de 1998. O soro obtido dos animais foi avaliado por meio da Reação de Imunofluorescência Indireta (RIFI) utilizando como antígeno a cepa padrão NC-1 deN. caninum. Observaram-se 245 animais reagentes (25,4% de positividade), sendo 161 (27,5%) machos e, 84 (22,3%) fêmeas. Dos animais de zona urbana, rural e mista 223 (25,8%),11(16,9%) e 11(33,3%), respectivamente, foram reagentes à prova de RIFI. Todos os 11 municípios apresentaram cães soropositivos com valores de ocorrência que variaram de 8,9% a 53,5%. Observou-se percentual de positividade menor em cães até um ano (16,2%) quando comparados àqueles entre 1 a 4 anos e superior a 4 anos (28,4 % e 28,0%, respectivamente) que não apresentaram diferença entre si. Os resultados obtidos caracterizaram soropositividade para N. caninum em cães pertencentes a todos os municípios da Microrregião da Serra de Botucatu evidenciando a ampla distribuição do agente na região.

Incidence and transplacental transmission of Neospora caninum in primiparous females from Bos indicus slaughtered in Presidente Pradente, São Paulo, Brazil

To produce an epidemiological map of neosporosis in Brazil and identify the types of transmission of this disease, the present study evaluated the occurrence of Neospora caninum in Nelore cattle (Bos indicus) in Presidente Prudent, west region of São Paulo state; its vertical transmission; and the early stage in which fetuses are infected. To achieve this, serum samples from 518 slaughtered pregnant heifers and their fetuses were tested by ELISA technique and fetal brain tissues subjected to PCR. One hundred and three heifers (19.88%) had antibodies to N. caninum, as well as 38 (36.8%) of fetuses from 4 months of gestation. The conventional PCR failed to detect N. caninum DNA. These findings show that neosporosis occurs in the area studied and that it may be transmitted the transplacental route, althought N. caninum had not detected in brain tissue from non-aborted fetuses. The use of nested PCR it would be applied to increase the sensitivy of test.

Freqüência de anticorpos anti-Neospora caninum em soros de caprinos do estado de São Paulo e sua relação com o manejo dos animais

Com o objetivo de se avaliar a freqüência de caprinos leiteiros soropositivos para Neospora caninum, no estado de São Paulo, e se verificarem possíveis associações com idade, sexo e problemas reprodutivos, nos capris, e, também, presença de cães, nas propriedades, foram obtidos soros de 923 caprinos de ambos os sexos e idade acima de 3 meses. Os animais eram provenientes de 17 propriedades de diferentes municípios. Para o diagnóstico, foi utilizado o teste de aglutinação para Neospora (NATe25), e, em todos os capris, aplicou-se um inquérito a partir do qual se obtiveram informações epidemiológicas e de esfera reprodutiva. Todos os resultados estatísticos foram discutidos no nível de 5% de significância. Assim, chegou-se à conclusão de que a freqüência percentual de positividade para N. caninum foi de 19,77%, e, em apenas uma propriedade, não houve registro de animal soropositivo, o que revela difusão do agente, no Estado. Não foram verificadas diferenças significativas entre freqüências de positividade quanto ao sexo, idade ou problemas reprodutivos. Porém, ressalta-se que a presença de cães, nos capris, foi associada a uma maior freqüência de caprinos soropositivos a N. caninum. A representação geográfica da distribuição de caprinos soropositivos para o protozoário, em mapa coroplético em hachuras, pode implicar em um ganho considerável para estudos da epidemiologia geográfica, na elaboração de um planejamento de controle da enfermidade.

Detection and molecular analysis of Toxoplasma gondii and Neospora caninum from dogs with neurological disorders

Introduction: Toxoplasma gondii and Neospora caninum are related Apicomplexa parasites responsible for systemic diseases in many species of animals, including dogs. Methods: This study aimed to determine the occurrence of T. gondii and N. caninum infections in 50 dogs with neurological signs that were admitted to the Veterinary Hospital of Universidade Estadual Paulista, City of Botucatu, Brazil. All animals were screened for antibodies using an immunofluorescent antibody test for both parasites. Tissues of positive animals were bioassayed in mice (T. gondii) and gerbils (N. caninum), and DNA was analyzed using the polymerase chain reaction (PCR). Positive samples for T. gondii by PCR were typed using restriction fragment length polymorphism-PCR for 11 markers: SAG1, SAG2 (5'-3'-SAG2 and alt.SAG2), SAG3, Btub, GRA6, L358, c22-8, c29-6, PK1 and Apico, and CS3 marker for virulence analysis. Results: Specific antibodies were detected in 11/50 (22%; 95% confidence interval (CI95%), 12.8-35.3%) animals for T. gondii and 7/50 (14%; CI95%, 7.02-26.3%) for N. caninum. In the bioassay and PCR, 7/11 (63.6%; CI95%, 34.9-84.8%) samples were positive for T. gondii and 3/7 (42.9%; CI95% I, 15.7-75.5%) samples were positive for N. caninum. Three different genotypes were identified, but only 1 was unique. Conclusions: These data confirm the presence of T. gondii and N. caninum in dogs from Brazil, indicating the importance of this host as a sentinel of T. gondii for human beings, and the genotypic variation of this parasite in Brazil.

Serological profile of Toxoplasma gondii and Neospora caninum infection in commercial sheep from São Paulo State, Brazil

Neosporosis and toxoplasmosis are two important infections in young and adult sheep, leading to low production and abortion. This study aimed to determine the frequency of antibodies to Toxoplasma gondii and Neospora caninum in sheep from the eastern region of São Paulo State, Brazil. Serum samples (382) were collected from the sheep and assayed for T. gondii through modified agglutination test (MAT) and indirect fluorescent antibody test (IFAT), and for N. caninum antibodies, through IFAT, with cut-off titers equal to 16 (T. gondii) and 25 (N. caninum). All frozen samples were sent to the Center for Zoonoses Research (NUPEZO), Department of Veterinary Hygiene and Public Health (DHSVP), FMVZ, UNESP, for serological tests. A total of 71/382(18.6%) samples reacted to T. gondii, especially at titers 16 (28; 39.4%), 64(15; 21.1%), 256 (21; 29.6%) and 1024 (6; 8.5%) by MAT, and 16(34: 47.9%), 64 (18; 25.4%), 256 (14; 19.7%) and 1024 (5; 7%) by IFAT. As regards N. caninum, 49/382 (12.8%) samples reacted at titers 25 (17; 34.7%), 50 (11; 22.5%), 100 (11; 22.5%), and >= 200 (10; 20.4%). These animals presented infection but no clinical signs. Six and ten animals had high titers for toxoplasmosis and neosporosis. No significant association was observed between antibodies for both parasites (P = 0.535) according to Fisher's exact test, and no correlation was found between T. gondii (MAT) and N. caninum antibody titers (r = -0.0068; P=0.895), T. gondii (IFAT) and N. caninum antibody titers (r = -0.0025; P = 0.961). Thus, T. gondii and N. caninum infections were observed in farms located in São Paulo State, where sheep play an important economical role for the national and regional business. (C) 2010 Elsevier By. All rights reserved.

Neospora caninum infection dynamics in dairy cattle

Neospora caninum is considered in many countries as one of the key abortion agents in cattle. This study aims to investigate the parasite behavior in dairy cattle in the municipality of Avar,, SP, Brazil, where abortions frequently occur. An ELISA was performed to compare two samplings on a total of 615 animals; tests were performed in the same herds with a gap of 3 years. An increase in the percentage of reactive animals was observed, ranging from 21.6% at the first sampling to 38.9% at the second sampling. of the 176 animals tested at both samplings, 61.93% retained a non-reactive status, 15.9% retained a reactive status, 19.88% switched from non-reactive to reactive and 2.27% switched from reactive to non-reactive. of the 100 animals with reproductive disturbances, 50% presented anti-Neospora antibodies, thereby indicating the presence of the protozoa. When comparing cows and their respective female offspring, a predominance of horizontal infection was observed. Moreover, considering the significant percentage of animals that switched from non-reactive to reactive and the abundant presence of dogs among the herds, the N. caninum transmission may be attributed to presence of carnivores.

Intermolecular interactions and characterization of the novel factor Xa exosite involved in macromolecular recognition and inhibition: Crystal structure of human Gla-domainless factor Xa complexed with the anticoagulant protein NAPc2 from the hematophagous nematode Ancylostoma caninum

NAPc2, an anticoagulant protein from the hematophagous nematode Ancylostoma caninum evaluated in phase-II/IIa clinical trials, inhibits the extrinsic blood coagulation pathway by a two step mechanism, initially interacting with the hitherto uncharacterized factor Xa exosite involved in macromolecular recognition and subsequently inhibiting factor VIIa (K-i = 8.4 pM) of the factor VIIa/tissue factor complex. NAPc2 is highly flexible, becoming partially ordered and undergoing significant structural changes in the C terminus upon binding to the factor Xa exosite. In the crystal structure of the ternary factor Xa/NAPc2/selectide complex, the binding interface consists of an intermolecular antiparallel beta-sheet formed by the segment of the polypeptide chain consisting of residues 74-80 of NAPc2 with the residues 86-93 of factor Xa that is additional maintained by contacts between the short helical segment (residues 67-73) and a turn (residues 26-29) of NAPc2 with the short C-terminal helix of factor Xa (residues 233-243). This exosite is physiologically highly relevant for the recognition and inhibition of factor X/Xa by macromolecular substrates and provides a structural motif for the development of a new class of inhibitors for the treatment of deep vein thrombosis and angioplasty. (c) 2006 Elsevier Ltd. All rights reserved.

Serological survey of Neospora caninum in small ruminants from Pernambuco State, Brazil

A infecção por Neospora caninum é uma importante causa de abortos em bovinos, assim como mortalidade neonatal em caprinos e ovinos. Uma pesquisa sorológica de anticorpos anti-N. caninum foi realizada no município de Ibimirim (PE, Brasil). Os resultados ao teste de imunofluorescência revelaram que 26,6% (85/319) dos caprinos e 64,2% (52/81) dos ovinos foram positivos. A reatividade à sorologia foi associada com a idade nos caprinos (p < 0,01) e ovinos (p > 0,05), com maior ocorrência nos animais mais velhos. Estes resultados indicam exposição a N. caninum entre pequenos ruminantes na área estudada.

Toxoplasma gondii and Neospora caninum serological status of different canine populations from Uberlândia, Minas Gerais

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)