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1.
An Acad Bras Cienc ; 91(4): e20190439, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800709

RESUMO

This study aimed to evaluate the frequency of Neospora caninum antibodies in rodents from the Island of Fernando de Noronha, Brazil, and to contribute to epidemiological data on neosporosis in this region. Blood samples were collected from 154 black-rats (Rattus rattus) and 12 rock-cavies (Kerodon rupestris). The search for anti-N. caninum antibodies was made using the NAT technique, with a cut-off of 1:20. The frequency of positive mice was 5.19% (8/154 - 1:20 titer) and all rock-cavies were negative. The low frequency of antibodies against N. caninum in rodents found in the Island shows the low contamination of the environment where these animals live.


Assuntos
Anticorpos Antiprotozoários/sangue , Neospora/imunologia , Roedores/parasitologia , Animais , Brasil , Ratos , Roedores/classificação
2.
Parasitol Res ; 118(12): 3535-3542, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31701296

RESUMO

Neospora caninum causes neosporosis, a leading cause of bovine abortion worldwide. Uruguay is a developing economy in South America that produces milk to feed seven times its population annually. Naturally, dairy production is paramount to the country's economy, and bovine reproductive failure impacts it profoundly. Recent studies demonstrated that the vast majority of infectious abortions in dairy cows are caused by N. caninum. To delve into the local situation and contextualize it within the international standing, we set out to characterize the Uruguayan N. caninum strains. For this, we isolated four distinct strains and determined by microsatellite typing that these represent three unique genetic lineages, distinct from those reported previously in the region or elsewhere. An unbiased analysis of the current worldwide genetic diversity of N. caninum strains known, whereby six typing clusters can be resolved, revealed that three of the four Uruguayan strains group closely with regional strains from Argentina and Brazil. The remaining strain groups in an unrelated genetic cluster, suggesting multiple origins of the local strains. Microsatellite typing of N. caninum DNA from fetuses opportunistically collected from local dairy farms correlated more often with one of the isolates. Overall, our results contribute to further understanding of genetic diversity among strains of N. caninum both regionally and worldwide.


Assuntos
Aborto Animal/parasitologia , Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Neospora/genética , Neospora/isolamento & purificação , Animais , Argentina , Brasil , Bovinos , Doenças dos Bovinos/epidemiologia , Coccidiose/parasitologia , Feminino , Repetições de Microssatélites , Neospora/classificação , Neospora/imunologia , Filogenia , Gravidez , Uruguai
3.
Vet Parasitol ; 276: 108990, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31775103

RESUMO

Neospora caninum infection is an important cause of neuromuscular disease in dogs and abortion in cattle, leading to significant economic losses in beef and dairy industries. The protective immunity against apicomplexan parasites, specifically Toxoplasma gondii and N. caninum, is typically achieved by inducing an IL-12-driven Th1 immune response. IL-12 stimulates IFN-γ production, which activates Inducible Nitric Oxide Synthase (iNOS) and promotes consequent Nitric Oxide (NO) synthesis, classically described as one of the main effector mechanisms for parasite elimination. Here, we aimed to evaluate the role played by iNOS during N. caninum infection. Our results show that N. caninum infection in C57BL/6 wild type (WT) mice induce NO production in vivo and in vitro. In agreement, iNOS deficient mice, as well as WT mice treated with iNOS inhibitor aminoguanidine, succumbed during acute infection with a dose lethal to 50 % of the WT mice, and presented significant increase in parasite load when submitted to sub-lethal infection protocols. Interestingly, the lack of control of parasite proliferation observed in iNOS-/- mice was associated with notable CNS inflammation and increased production of the main systemic proinflammatory cytokines (IL-12, IFN-γ, IL-6, TNF and IL-17A). Taken together, our findings show that iNOS plays an important role in restricting N. caninum replication, while also modulates the inflammatory process induced by the infection.


Assuntos
Coccidiose/enzimologia , Neospora/imunologia , Óxido Nítrico Sintase Tipo II/fisiologia , Animais , Coccidiose/parasitologia , Coccidiose/patologia , Interferon gama/análise , Subunidade p40 da Interleucina-12/análise , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/deficiência
4.
Vet Parasitol ; 276: 108994, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31778941

RESUMO

Neospora caninum is a protozoan parasite (Phylum Apicomplexa) that has been recently suggested as a relevant cause of reproductive disorders in small ruminants. The aim of the present study is to develop and validate a new serological test based on time resolved fluorescency using N. caninum GRA7 recombinant antigen (GRA7-TRFIA) for the detection of N. caninum antibodies in sheep. A total of 346 serum samples (208 from experimentally infected sheep, 117 from a dairy farm with a previous history of Neospora-associated abortion, and 21 negative sera) were used. The validation of the new assay was performed by the evaluation of assay precision, analytical sensitivity (Se), accuracy and cross reactivity. In the experimentally infected sheep, antibody kinetics was compared between GRA7-TRFIA and an in house N. caninum tachyzoite soluble extract-based ELISA (NcSALUVET ELISA) by Wilcoxon matched-pairs signed rank test. The cut-off and diagnostic Se and specificity (Sp) of GRA7-TRFIA was estimated by ROC analysis with field samples. In addition, concordance and correlation between GRA7-TRFIA and a commercial ELISA and NcSALUVET ELISA were assessed by kappa value and Spearman correlation coefficient, respectively. Overall, GRA7-TRFIA showed an adequate precision, analytical Se and accuracy to detect anti-N. caninum antibodies in ovine serum, and no cross reactivity with the closely related protozoan Toxoplasma gondii. In naturally infected sheep, 100% Se and 95.35% Sp were obtained for a cut-off point of 62.68 Units of Fluorometry for N. caninum (UFN). Moreover, GRA7-TRFIA allowed earlier detection of N. caninum infection than NcSALUVET ELISA in experimentally infected sheep.


Assuntos
Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Coccidiose/veterinária , Neospora/imunologia , Doenças dos Ovinos/imunologia , Animais , Coccidiose/imunologia , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Imunoensaio de Fluorescência por Polarização , Fluorometria/veterinária , Imunoglobulina G/sangue , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/parasitologia
5.
Rev Bras Parasitol Vet ; 28(4): 816-820, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618304

RESUMO

Toxoplasma gondii and Neospora caninum are Apicomplexan intracellular protozoan parasites that affect numerous animal species, thus leading to severe diseases and economic losses, depending on the vertebrate species involved. The role of the avian species in maintaining and transmission of these coccidia has been studied for several years as they tend to serve as a potential source of infection for mammals and humans. The present study aimed to assess the serological exposure of Orinoco goose (Neochen jubata) to T. gondii and N. caninum. Between 2010 and 2013, 41 free-ranging Orinoco geese were captured in the Araguaia River, Brazil. The presence and titration of IgY antibodies to both coccidia were assayed via indirect immunofluorescent antibody test (IFAT). While IgY antibodies for N. caninum were present in 5 animals, with titers of 20, the antibodies for T. gondii were found in 35 animals, with titers ranging from 20 to 640. Considering that the Orinoco goose's meat is consumed by the local population in the studied area, it may represent an important source of T. gondii infection for humans. Due to its migratory behavior, this goose may play a pivotal role in the natural dispersion of both parasites. Furthermore, molecular studies are required for genotyping the isolates of T. gondii that occurs in this avian species.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças das Aves/diagnóstico , Coccidiose/veterinária , Gansos/parasitologia , Neospora/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/diagnóstico , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Brasil/epidemiologia , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Coccidiose/parasitologia , Técnica Indireta de Fluorescência para Anticorpo , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/parasitologia
6.
Vet Immunol Immunopathol ; 217: 109955, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31639586

RESUMO

The purpose of this work was to characterize the cellular phenotype in inflammatory infiltrates of fetal tissues from pregnant heifers immunized and experimentally challenged with Neospora caninum. Fetuses from 20 heifers separated into 5 groups were obtained. The experiment was designed as follow: Group A, heifers inoculated intravenously with live tachyzoites of Argentine strain NC-6 (n = 4); Group B heifers inoculated subcutaneously with soluble native antigen from the same strain formulated with immune stimulant complexes (ISCOMs) (n = 4); Group C heifers inoculated with recombinant proteins, rNcSAG1, rNcHSP20, rNcGRA7 formulated with ISCOMs (n = 4), Group D heifers inoculated subcutaneously with sterile phosphate buffered solution (n = 4) and Group E heifers inoculated subcutaneously with antigen-free ISCOMs (n = 4). Experimental challenge was performed at 70 days of gestation and all heifers were euthanized 34 days later. Fetal tissues were taken for histological studies. Inflammatory lesions were observed in brain and lung, and immunhistochemistry was used to identify CD3+, CD20+ and MHC II+ cells. The majority of the cells that infiltrate and circumscribe the lesions in the brain and lung tissue expressed MHC II antigen; varying between 70-90% of the total cellular infiltrate. CD3+ cells were also present within the lesions, contributing to up to 30% of the inflammatory cells. CD20+ cells appeared as a marginal group, in some cases, with a range between 10 and 25%. As expected, the immunolabeling of MHC II + and CD3 + cells in fetal tissues was associated with fetal infection with N. caninum. There were statistically significant differences in the distribution and population of the inflammatory infiltrate in relation to the immunogenic treatment and the type of tissue, with inflammatory cells being markedly less extensive fetuses from group A (dams previously exposed to N. caninum) and in brain tissue. This work showed that Neospora-infection induced MHC II+ and CD3+ cells in bovine fetuses from dams receiving experimental vaccines.


Assuntos
Coccidiose/imunologia , Feto/imunologia , Imunização/veterinária , Neospora/imunologia , Vacinas Protozoárias/imunologia , Animais , Encéfalo/citologia , Encéfalo/imunologia , Bovinos , Doenças dos Bovinos/imunologia , Feminino , Feto/citologia , Imuno-Histoquímica , Pulmão/citologia , Pulmão/imunologia , Gravidez
7.
Parasitol Res ; 118(10): 2945-2955, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31485864

RESUMO

The aim of the present study was to characterize the specific immune response in prepubertal female calves inoculated with Neospora caninum. Forty-eight N. caninum-seronegative 6-month-old Angus female calves were randomly allocated into two groups: group A calves were inoculated subcutaneously (sc) with 1 × 106 tachyzoites of the low virulence NC-Argentina LP1 isolate in sterile phosphate-buffered saline (PBS); group B calves were mock inoculated sc with sterile PBS. Calves from group A developed a specific immune response characterized by the production of IgG antibodies and the expression of IFN-γ and TNF-α cytokines. Animals did not present any febrile reaction or reactions at the site of inoculation. Although chronic N. caninum infection was developed in 50% of calves of group A after inoculation, according to the presence of antibodies against rNc-SAG4, antigen characteristic of bradyzoites, N. caninum antibodies dropped below the cut-off of ELISA from day 210 post-inoculation onwards. Future trials using the same group of inoculated animals will allow the characterization of the evolution of the immune response during pregnancy and to determine whether the immunization with the local isolate is able to prevent congenital transmission and to protect against heterologous challenges.


Assuntos
Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Doenças dos Bovinos/imunologia , Coccidiose/veterinária , Neospora/imunologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/imunologia , Coccidiose/parasitologia , Citocinas/metabolismo , Feminino , Imunização/veterinária , Neospora/patogenicidade , Distribuição Aleatória
8.
Vet Res ; 50(1): 68, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547877

RESUMO

Parameters such as pathogen dose and inoculation route are paramount in animal models when studying disease pathogenesis. Here, clinical findings, including foetal mortality, parasite transmission rates and lesion severity, and immune responses were evaluated in Asturiana pregnant heifers at day 110 of gestation challenged with a virulent (Nc-Spain7) Neospora caninum isolate. Four different doses of parasite tachyzoites were inoculated intravenously (IV1, 107 parasites, n = 6; IV2, 105, n = 6; IV3, 103, n = 6; and IV4, 102, n = 5), and the subcutaneous (SC) inoculation route was also assessed for the dose of 105 tachyzoites (SC, n = 6). In addition, a control group (n = 4 pregnant heifers) was evaluated. Foetal death was observed in all infected groups from 25 to 62 days post-infection, varying with the dose (IV1:4/6, IV2:3/6; IV4:2/5, IV3:1/6), and was three times less frequently associated with the SC route than IV inoculation (1/6 vs. 3/6). A dose-dependent effect for parasite loads in placental and foetal brain tissues was also detected. After SC challenge, a reduced number of tachyzoites were able to reach foetal brain tissues, and no lesions were observed. In calves, specific IgG responses in precolostral sera were mainly associated with high-dose groups (IV1 [100.0%] and IV2 [66.7%]), and cerebral parasite DNA detection was scarce (3/18). In dams, IFN-γ production and the dynamics of anti-N. caninum IgG antibodies varied with the dose, and the cell-mediated immune response was also found to be route-dependent. Our results confirm the influence of parasite dose and inoculation route on the outcome and dynamics of bovine neosporosis at mid-gestation.


Assuntos
Doenças dos Bovinos/mortalidade , Coccidiose/veterinária , Imunidade Celular , Neospora/imunologia , Complicações Parasitárias na Gravidez/veterinária , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/mortalidade , Coccidiose/parasitologia , Feminino , Feto/parasitologia , Injeções Intravenosas/veterinária , Gravidez , Complicações Parasitárias na Gravidez/mortalidade , Complicações Parasitárias na Gravidez/parasitologia , Distribuição Aleatória , Vacinação/veterinária
9.
Rev Bras Parasitol Vet ; 28(3): 383-394, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31390432

RESUMO

This study evaluated the seroprevalence of Toxoplasma gondii, Neospora caninum and Leptospira spp. in dogs from Foz do Iguaçu, Paraná, Brazil. Indirect immunofluorescent antibody test was used to detect antibodies anti-T.gondii and anti-N. caninum. Immunoenzymatic assay and microscopic serum agglutination were used for screening antibodies anti-T.gondii and anti-Leptospira spp., respectively. The results were: 67.02% of the samples reactive for T.gondii and 1.38% for N. caninum, both without statistically significant variables. For Leptospira spp. the results indicated seroprevalence of 23.11%. The analysis of the variables without distinction of serovar showed association for intrinsic characteristics as breed, age, nutritional status and dog category. The extrinsic variables as city region and access to the street presented association (p<0.05). The most prevalent serovars were: Canicola 59.47%; Bratislava 13.07% and Butembo 15.68%. Variables that make up the adjusted multiple analysis model using Leptospira spp. were: age, breed and nutritional status; serovar Canicola, sex, nutritional status and area (p<0.05); serovar Bratislava, lymphadenomegaly and presence of fleas (p<0.05). Given the results obtained, dogs can be used as sentinels for toxoplasmosis and leptospirosis in Foz do Iguaçu and other cities with similar outcomes. In addition, preventive measures should be taken by health authorities because they are zoonoses and humans are also at risk.


Assuntos
Coccidiose/veterinária , Doenças do Cão/epidemiologia , Leptospirose/veterinária , Toxoplasmose Animal/epidemiologia , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Doenças do Cão/diagnóstico , Cães , Ensaio de Imunoadsorção Enzimática , Técnica Indireta de Fluorescência para Anticorpo , Leptospira/imunologia , Leptospirose/diagnóstico , Leptospirose/epidemiologia , Neospora/imunologia , Fatores de Risco , Estudos Soroepidemiológicos , Toxoplasma/imunologia , Toxoplasmose Animal/diagnóstico
10.
Rev Bras Parasitol Vet ; 28(3): 403-409, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31390435

RESUMO

To estimate the seroprevalence of Toxoplasma gondii and Neospora caninum, using an indirect immunofluorescent assay (IFA), and identify the risk factors associated, serum samples were collected from 1,070 pigs from 320 backyard pig farming in the of Mato Grosso state. The animal-level seroprevalence of T. gondii and N. caninum was 32.48% and 13.49%, respectively, with a herd seroprevalence of 55.63% for T. gondii and 27.81% for N. caninum. Feeding the animals with leftovers increases the probability of the presence of anti-T. gondii antibodies in pigs by 1.09-fold. Unlike to T. gondii, feeding with leftovers was found to be negatively associated with N. caninum seropositivity in farm-level analysis and in the animal-level model, so decreasing the chances of positivity. Yet, age was considered a risk factor for N. caninum seropositivity. Further studies are necessary to evaluate the impact of T. gondii infection on backyard pig farming production, and its importance as a source of toxoplasmosis infection in humans in the Mato Grosso state, as well as, the role of domestic pigs in the epidemiology of neosporosis.


Assuntos
Anticorpos Antiprotozoários/sangue , Coccidiose/veterinária , Neospora/imunologia , Doenças dos Suínos/epidemiologia , Suínos/parasitologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Animais , Brasil/epidemiologia , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Masculino , Fatores de Risco , Estudos Soroepidemiológicos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/parasitologia , Toxoplasmose Animal/diagnóstico
11.
Exp Parasitol ; 204: 107731, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31374185

RESUMO

Neospora caninum is an obligate intracellular parasite related to cases of abortion and fertility impairment in cattle. The control of the parasite still lacks an effective protective strategy and the understanding of key mechanisms for host infection might be crucial for identification of specific targets. There are many proteins related to important mechanisms in the host cell infection cycle such as adhesion, invasion, proliferation and immune evasion. The surface proteins, especially SRS (Surface Antigen Glycoprotein - Related Sequences), have been demonstrated to have a pivotal role in the adhesion and invasion processes, making them potential anti-parasite targets. However, several predicted surface proteins were not described concerning their function and importance in the parasite life cycle. As such, a novel SRS protein, NcSRS57, was described. NcSRS57 antiserum was used to detect SRS proteins by immunofluorescence in parasites treated or not with phosphatidylinositol-specific phospholipase C (PI-PLC). The treatment with PI-PLC also allowed the identification of NcSRS29B and NcSRS29C, which were the most abundant SRS proteins in the soluble fraction. Our data indicated that SRS proteins in N. caninum shared a high level of sequence similarity and were susceptible to PI-PLC. In addition, the description of the SRS members, regarding abundance, function and immunogenicity will be useful in guiding specific methods to control the mechanism of adhesion and invasion mediated by these surface proteins.


Assuntos
Antígenos de Protozoários/metabolismo , Antígenos de Superfície/metabolismo , Neospora/química , Fosfoinositídeo Fosfolipase C/farmacologia , Proteínas de Protozoários/metabolismo , Animais , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Antígenos de Superfície/genética , Antígenos de Superfície/imunologia , Clonagem Molecular , DNA de Protozoário/isolamento & purificação , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Soros Imunes/imunologia , Soros Imunes/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Confocal , Neospora/efeitos dos fármacos , Neospora/genética , Neospora/imunologia , Fosfoinositídeo Fosfolipase C/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Espectrometria de Massas em Tandem , Fosfolipases Tipo C/metabolismo , Fosfolipases Tipo C/farmacologia , Células Vero
12.
Rev Bras Parasitol Vet ; 28(2): 221-228, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31271639

RESUMO

Geese, ducks, mallards, and swans are birds of the order Anseriformes, which are found in the wild, in zoos and parks, and raised for meat consumption. Toxoplasma gondii, Sarcocystis sp., and Neospora caninum are protozoans of several species of animals. Wild and domestic birds can serve as intermediate hosts, disseminators and potential sources of infection of these protozoa to humans through contaminated meat. The aims of this study were: (i) to perform a serological survey of T. gondii, Sarcocystis sp. and N. caninum in geese (Anser sp.) from public parks and from captivity and (ii) to compare seroprevalence between these two locations. Antibodies were detected by Immunofluorescence antibody test using the serum of 149 geese. Antibodies to Sarcocystis sp., T. gondii, and N. caninum were detected in 28.18%, 18% and 0.67% of geese, respectively; 57% of geese from urban parks and 26.53% of geese from captivity were seropositive for at least one protozoa. The results indicate environmental contamination, particularly for the occurrence of antibodies against T. gondii - a zoonosis that causes toxoplasmosis and is transmitted through oocyte ingestion. This is the first serological survey of T. gondii, Sarcocystis sp. and N. caninum in geese from urban parks in Curitiba, Brazil.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Gansos/parasitologia , Neospora/imunologia , Sarcocystis/imunologia , Toxoplasma/imunologia , Animais , Brasil/epidemiologia , Imunofluorescência , Estudos Soroepidemiológicos , População Urbana
13.
Acta Trop ; 198: 105094, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31323195

RESUMO

Neospora caninum is the etiological agent of neosporosis, a worldwide infectious disease recognized as the major cause of abortions and reproductive failures in livestock, responsible for significant economic losses in cattle industries. Currently, there are not cost-effective control options for this pathology, and the development of a vaccine involving new and integrated approaches is highly recommended. In this study, we evaluated the immunogenic and protective efficacy, as well as the potential DIVA (Differentiation of Infected from Vaccinated Animals) character of a recombinant subunit vaccine composed by the major surface antigen from N. caninum (NcSAG1) and the carrier/adjuvant heat shock protein 81.2 from Arabidopsis thaliana (AtHsp81.2) in a mouse model of congenital neosporosis. BALB/c female mice were intraperitoneal (i.p.) immunized with a mixture of equimolar quantities of rNcSAG1 and rAtHSP81.2 or each protein alone (rNcSAG1 or rAtHsp81.2). The vaccine containing a mixture of rNcSAG1 and rAtHsp81.2 significantly enhanced the production of specific anti-rNcSAG1 total IgG (tIgG), IgG1 and IgG2a antibodies in immunized mice when compared to control groups (non-vaccinated and rAtHsp81.2 immunized mice) as well as to the group of mice immunized only with the antigen (rNcSAG1). In addition, partial protection against vertical transmission and improvement of the offspring survival time was observed in this group. On the other hand, rAtHsp81.2 induced the production of specific anti-rAtHsp81.2 tIgG, allowing us to differentiate vaccinated from infected mice. Despite further experiments have to be made in cattle to test the capability of this vaccine formulation to differentiate vaccinated from infected animals in the field, our results suggest that the formulation composed by rNcSAG1 and rAtHsp81.2 could serve as a basis for the development of a new vaccine approach against bovine neosporosis.


Assuntos
Antígenos de Protozoários/imunologia , Coccidiose/prevenção & controle , Transmissão Vertical de Doença Infecciosa/prevenção & controle , Complicações Parasitárias na Gravidez/prevenção & controle , Vacinas Protozoárias/imunologia , Animais , Anticorpos Antiprotozoários , Coccidiose/parasitologia , Feminino , Imunoglobulina G , Camundongos , Camundongos Endogâmicos BALB C , Neospora/imunologia , Gravidez , Vacinação , Vacinas Sintéticas/imunologia
14.
Rev Bras Parasitol Vet ; 28(2): 215-220, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31215607

RESUMO

Our objective was to identify the direct and indirect presence of Neospora caninum in dairy cattle and their aborted fetuses from Lima, Peru. A total 219 blood samples obtained from dairy cattle with records of spontaneous abortion were collected to detect antibodies against N. caninum in serum with indirect ELISA and search for risk-factor associations. 68 fetal aborted tissue samples of these cows were analyzed by PCR, indirect ELISA and histopathology assay to detect N. caninum presence. The prevalence ratio (PR) and 95% confidence intervals (CI) were estimated. Univariate analysis was performed using the chi-squared test. Among the 68 aborted fetuses collected, 10 (15%) were positive in at least two diagnostic tests. Among 219 serum samples, 46.6% (95% CI: 40.0%-53.3%) were positive. Cows with 4 years or older (PR: 7.10; 95% CI: 4.89-10.67) and multiparous (PR: 1.76; 95% CI: 1.11-2.80) were found to be more likely to possess N. caninum antibodies. This study detects presence of N. caninum in dairy cattle and their aborted fetus from Lima valley, suggesting biosecurity management improve to neosporosis control.


Assuntos
Aborto Animal/epidemiologia , Anticorpos Antiprotozoários/sangue , Doenças dos Bovinos/epidemiologia , Coccidiose/veterinária , Neospora , Aborto Animal/parasitologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/complicações , Coccidiose/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Neospora/genética , Neospora/imunologia , Peru/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos
15.
Rev Bras Parasitol Vet ; 28(2): 245-257, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31215610

RESUMO

This is a cross-sectional study to assess the presence of antibodies in ruminants against selected pathogens associated with reproductive disorders in cattle in four Brazilian states, including the zoonotic agent Coxiella burnetii. The used tests were Virus Neutralization Assay for IBR and BVD, Microscopic Agglutination Test for Leptospira spp., Indirect Fluorescent Antibody Test (IFAT) for C. burnetii and Toxoplasma gondii, and Enzyme-Linked Immunosorbent Assay for Neospora caninum and Trypanosoma vivax. Seropositivity for C. burnetii was 13.7% with titers from 128 to 131,072; 57.8% for BoHV-1, with titers between 2 and 1,024; 47.1% for BVDV-1a, with titers from 10 to 5,120; 89.2% for N. caninum; 50% for T. vivax; and 52.0% for Leptospira spp., with titers between 100 to 800 (the following serovars were found: Tarassovi, Grippotyphosa, Canicola, Copenhageni, Wolffi, Hardjo, Pomona and Icterohaemorrhagiae); 19.6% for T. gondii with titer of 40. This is the first study that has identified C. burnetii in cattle associated with BoHV and BVDV, N. caninum, Leptospira spp., T. gondii and T. vivax. Thus, future studies should be conducted to investigate how widespread this pathogen is in Brazilian cattle herds.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/complicações , Doenças dos Bovinos/epidemiologia , Coccidiose/veterinária , Leptospirose/veterinária , Febre Q/veterinária , Toxoplasmose Animal/complicações , Tripanossomíase Africana/veterinária , Aborto Animal , Testes de Aglutinação , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/diagnóstico , Doença das Mucosas por Vírus da Diarreia Viral Bovina/epidemiologia , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/virologia , Coccidiose/complicações , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Coxiella burnetii/imunologia , Estudos Transversais , Vírus da Diarreia Viral Bovina/imunologia , Endometrite/etiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Infertilidade Feminina/etiologia , Leptospira/imunologia , Leptospirose/complicações , Leptospirose/diagnóstico , Leptospirose/epidemiologia , Neospora/imunologia , Febre Q/complicações , Febre Q/diagnóstico , Febre Q/epidemiologia , Estudos Soroepidemiológicos , Toxoplasma/imunologia , Toxoplasmose Animal/diagnóstico , Trypanosoma vivax/imunologia , Tripanossomíase Africana/complicações , Tripanossomíase Africana/diagnóstico , Tripanossomíase Africana/epidemiologia
16.
BMC Vet Res ; 15(1): 194, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31185969

RESUMO

BACKGROUND: Determining the infectious cause of abortion in cattle is difficult. This case-control study was set up to investigate the infectious causes of abortion by determining the seroprevalence of three reproductive pathogens in dairy cattle in Ecuador and their association with abortion: Brucella abortus, Neospora caninum and Coxiella burnetii. RESULTS: Ninety-five blood samples were obtained from cows that had experienced a mid- or late gestation abortion of their first calf and seventy-seven samples from a control group of cows with the same age that did not experience abortion problems. No antibodies were detected for B. abortus in any of the serum samples, but a high seroprevalence for both C. burnetii (52.9%) and N. caninum infection (21.5%) was found in group of cows. The seroprevalence of N. caninum infection in cattle that had experienced abortions was significantly higher (p < 0.05) than the seroprevalence in the control cows on one of the cattle farms, but no association between abortion and seropositivity for C. burnetii was found. CONCLUSION: We conclude that Neosporosis plays an important role in the epidemiology of abortion on one cattle farm, but that Q fever is apparently not an important cause for abortion in this setting.


Assuntos
Aborto Animal/epidemiologia , Doenças dos Bovinos/epidemiologia , Coccidiose/veterinária , Febre Q/veterinária , Aborto Animal/microbiologia , Aborto Animal/parasitologia , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antiprotozoários/sangue , Brucella abortus/imunologia , Brucelose Bovina/epidemiologia , Estudos de Casos e Controles , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Coccidiose/epidemiologia , Coxiella burnetii/imunologia , Indústria de Laticínios , Equador/epidemiologia , Feminino , Neospora/imunologia , Gravidez , Febre Q/epidemiologia , Estudos Soroepidemiológicos
17.
Exp Parasitol ; 202: 1-6, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31077732

RESUMO

Neospora caninum is an apicomplexan parasite distributed worldwide. Although a positive association between the presence of birds and abortions in cattle associated to N. caninum has been reported, the role of the birds in the epidemiologic cycle of the parasite is unknown. To the best knowledge, no experimental studies have evaluated N. caninum in the eared dove, Zenaida auriculata. Therefore, we aimed to determine whether Z. auriculat can act as intermediate host for N. caninum. Eighteen birds were divided into four groups, G1, G2, G3, and G4 (control); G1, G2 and G3 received 2 × 106 tachyzoites of NC-1 strain via different routes: subcutaneous, intramuscular, and intraperitoneal, respectively. G4 composed of three birds. Serum samples were collected weekly, and one bird each from G1, G2 and G3 was euthanized on the 7th and 14th day post-inoculation (dpi). The remaining birds were euthanized after the 28th dpi. Tissues from the doves were evaluated using histopathological analysis, PCR and dog bioassay to detect the parasite. Dogs were fed with tissues from the birds and monitored for 30 days. Serum samples were collected weekly from the dogs for serological analysis, and feces samples were collected daily until the end of the experiment for coproparasitological examinations. No dove showed clinical signs of the infection; however, all of them seroconverted after the inoculation, with stronger immunological response in the G3 birds. The lung tissue of one G3 bird showed positive PCR results; it was euthanized on the 7th dpi, and an inflammatory infiltrate was observed in the lung and kidney from this dove. The dogs did not shed oocysts or seroconverted. Our results indicate that the intraperitoneal route induced infection in the doves; however, the parasite may have been eliminated by the host, and the doves may be resistant to chronic infection.


Assuntos
Doenças das Aves/parasitologia , Coccidiose/veterinária , Columbidae/parasitologia , Neospora/isolamento & purificação , Animais , Anticorpos Antiprotozoários/análise , Bioensaio/métodos , Bioensaio/veterinária , Coccidiose/parasitologia , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Cães , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Imunoglobulina G/análise , Imuno-Histoquímica/veterinária , Rim/patologia , Fígado/patologia , Pulmão/patologia , Masculino , Músculo Esquelético/patologia , Neospora/genética , Neospora/imunologia , Reação em Cadeia da Polimerase/veterinária
18.
Parasite ; 26: 32, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31145075

RESUMO

Although Neospora caninum is an important veterinary pathogen, veterinarians in various areas including in Mainland China lack a full understanding of neosporosis distribution in dog populations. This study aims to determine the emergence of anti-N. caninum antibodies in canine populations classified based on breeders, herdsmen, and huntsmen in northeast mainland China. In addition, the risk factors associated with seropositivity were explored. An indirect immunofluorescent antibody test (IFAT) was performed on canine serum to determine seroprevalence. Logistic regression models were used to collect and analyze individual and management data, in order to determine high-reliability predictors of seroprevalence as well as the level of anti-N. caninum antibodies. Among the 476 dogs tested, 95 (20%) were seropositive. Mixed breed (OR 1.53), former strays (OR 1.38), dogs living on cattle farms (OR 2.30), hunting dogs (OR 1.22) as well as raw meat feeding (OR 1.66) were correlated (p < 0.05) with N. caninum infection. Interestingly, the seropositivity of dogs on cattle farms was higher (28%) than that of those (24.8%) living in breeding facilities (p < 0.05). A large number of seropositive dogs were found on cattle farms in the study region, suggesting horizontal transmission between dogs and cattle. Therefore, this source of infection should be studied further, and should be a strong consideration in differential diagnoses of dogs raised on cattle farms.


Assuntos
Anticorpos Antiprotozoários/sangue , Coccidiose/veterinária , Doenças do Cão/epidemiologia , Neospora/imunologia , Animais , Bovinos/parasitologia , China/epidemiologia , Coccidiose/epidemiologia , Doenças do Cão/parasitologia , Cães/parasitologia , Fazendas , Técnica Indireta de Fluorescência para Anticorpo , Modelos Logísticos , Fatores de Risco , Estudos Soroepidemiológicos
19.
Parasitol Res ; 118(6): 1875-1883, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30945017

RESUMO

Neosporosis in cattle is a globally important disease, causing abortions and significant economic losses if epidemic abortions occur. In Serbia, however, studies of Neospora caninum infection in cattle are few and are based on limited samples and/or from limited areas. We thus performed a nationwide study to examine the seroprevalence of N. caninum infection in a sample of cows randomly selected from dairy farms in 12 epidemiological units from throughout Serbia, as well as the possible transmission risk factors. Sera from a total of 1496 cattle were tested by competitive ELISA, and N. caninum-specific antibodies were shown in 7.2% animals (95% confidence interval CI, 6.6-7.9%), ranging from 2.2 to 12% across the epidemiological units. At least one seropositive animal was detected on 10.7% (95% CI, 9.7-11.8%) of farms, with a range of 5.9-25.9%. Logistic regression analysis showed that the single risk factor for infection in individual animals was keeping cows in loose-stalls (OR = 3.31, 95% CI = 1.95-5.60, P < 0.001). Risk factors for the presence of infection on farms also included housing in loose-stalls (OR = 18.49, 95% CI = 5.40-63.36, P < 0.001), and herd size > 100 animals (OR = 24.08, 95% CI = 3.85-150.50, P = 0.001). In view of the relatively low prevalence of infection showed at both the individual and farm level, this is the perfect time to undertake appropriate preventive measures to improve animal health and reduce economic losses.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças dos Bovinos/epidemiologia , Coccidiose/epidemiologia , Coccidiose/veterinária , Neospora/imunologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/transmissão , Coccidiose/transmissão , Ensaio de Imunoadsorção Enzimática/veterinária , Fazendas , Feminino , Neospora/isolamento & purificação , Gravidez , Prevalência , Fatores de Risco , Sérvia , Estudos Soroepidemiológicos
20.
Rev Soc Bras Med Trop ; 52: e20180440, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30994810

RESUMO

INTRODUCTION: The present study aimed to assess the seroprevalence and spatial distribution of Neospora caninum and Toxoplasma gondii in dogs. METHODS: Blood samples (n = 241) were collected and analyzed for the presence of anti-N. caninum and anti-T. gondii antibodies. The spatial distribution was evaluated using kernel density estimation (KDE). RESULTS: Anti-N. caninum and anti-T. gondii antibodies were detected in 24.06% (58/241) and 9.54% (23/241) of samples, respectively. A heterogeneous spatial distribution of positive dogs was observed across the city. CONCLUSIONS: These data are pivotal for better understanding the dynamics of infection caused by these protozoa in the canine population.


Assuntos
Anticorpos Antiprotozoários/sangue , Coccidiose/veterinária , Doenças do Cão/epidemiologia , Neospora/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Animais , Brasil/epidemiologia , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Doenças do Cão/diagnóstico , Cães , Feminino , Masculino , Fatores de Risco , Estudos Soroepidemiológicos , Análise Espacial , Toxoplasmose Animal/diagnóstico , População Urbana
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