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1.
Rev Bras Parasitol Vet ; 30(1): e022120, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33787719

RESUMO

Neospora caninum is an apicomplexan parasite that causes abortion in cattle, resulting in significant economic losses. There is no commercial treatment for neosporosis, and drug repositioning is a fast strategy to test possible candidates against N. caninum. In this article, we describe the effects of atovaquone, chloroquine, quinine, primaquine and tetracycline on N. caninum proliferation. The IC50 concentrations in N. caninum were compared to the current information based on previous studies for Plasmodium and Toxoplasma gondii, correlating to the described mechanisms of action of each tested drug. The inhibitory patterns indicate similarities and differences among N. caninum, Plasmodium and T. gondii. For example, atovaquone demonstrates high antiparasitic activity in all the analyzed models, while chloroquine does not inhibit N. caninum. On the other hand, tetracycline is effective against Plasmodium and N. caninum, despite its low activity in T. gondii models. The repurposing of antimalarial drugs in N. caninum is a fast and inexpensive way to develop novel formulations using well-established compounds.


Assuntos
Antimaláricos , Neospora/efeitos dos fármacos , Antimaláricos/farmacologia , Atovaquona/farmacologia , Cloroquina/farmacologia , Primaquina/farmacologia , Quinina/farmacologia , Tetraciclinas/farmacologia
2.
Rev Bras Parasitol Vet ; 30(1): e023020, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33605388

RESUMO

Neospora caninum is considered to be one of the main causes of abortion among cattle. The present survey was conducted in the municipality of Rolim de Moura, Rondônia State, Brazil. A questionnaire that investigates the epidemiological aspects of neosporosis was used in the analysis of risk factors associated with the animal-level and herd-level prevalence in dairy cattle. A total of 416 bovine blood samples were collected from 30 farms, and N. caninum antibody levels were measured by Indirect Fluorescent Antibody Test (IFAT). Analysis of dairy cattle serum samples revealed the presence of anti-N. caninum antibodies to be 47.36% (n = 197). Risk factors associated with N. caninum infection were the management system and access locations of dogs. The results of the present survey indicated that infection of dairy cattle with N. caninum is widespread in the studied region of Western Amazon, which has implications for prevention and control of neosporosis in this region. Therefore, integrated control strategies and measures are recommended to prevent and control N. caninum infection in dairy cattle. In addition, direct contact between dairy cattle, dogs and wild animals, which can influence the epidemiology of neosporosis, should be investigated further.


Assuntos
Doenças dos Bovinos , Coccidiose , Neospora , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/transmissão , Coccidiose/epidemiologia , Coccidiose/prevenção & controle , Coccidiose/transmissão , Coccidiose/veterinária , Indústria de Laticínios , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Análise Fatorial , Feminino , Neospora/imunologia , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos
3.
Rev Bras Parasitol Vet ; 30(1): e017520, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33533795

RESUMO

We investigated the occurrence of Toxoplasma gondii and Neospora caninum antibodies in pigs raised in the Northeast of Pará, Brazil. At Study I, convenience sampled 151 pigs at two slaughterhouses, with and without state inspection; and Study II, which assessed 159 pigs with probabilistic sampling from nine pig farms. Serological analysis was performed using indirect fluorescent antibody test for T. gondii and N. caninum with a cutoff of 64 and 50, respectively. Overall, 6.77% pigs were seropositive for T. gondii and 5.16% for N. caninum. In Study I, pigs slaughtered with and without state inspection presented similar occurrence for both coccidia (p>0.05). Study II found an association between N. caninum seropositivity and sludge discarded into the soil, feeding pigs with animal-based protein, subsistence system, and absence of nipple drinkers. No association was found for T. gondii. Pigs from Pará are a potential source of T. gondii infection to humans. To our best knowledge, this is the first study to report anti-N. caninum antibodies in the serum of pigs in Pará State, Brazilian Amazon.


Assuntos
Coccidiose , Neospora , Doenças dos Suínos , Toxoplasma , Toxoplasmose Animal , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Coccidiose/epidemiologia , Coccidiose/imunologia , Coccidiose/veterinária , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Neospora/imunologia , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia
4.
Rev Bras Parasitol Vet ; 30(1): e020820, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33533797

RESUMO

Livestock in the Amazon has grown significantly and, although neosporosis in cattle has been reported worldwide, there is no information about N. caninum in production systems in the state of Amazonas. The objective of this study was to determine the prevalence of anti-Neospora caninum antibodies in cattle, their spatial distribution and the risk factors associated with N. caninum infection in the state of Amazonas. Questionnaires were applied to farmers to assess risk factors associated with N. caninum infection. Blood samples were collected from 1,073 animals on 47 farms in 33 municipalities in the four Amazonian subpopulations. IgG anti-N.caninum antibodies were detected by the indirect fluorescence test, with a general prevalence of 30.2%, being seropositive in 43 farms (91.5%), with prevalence ranging from 2.2% to 69.2%. The highest number of high density points was found in subpopulation 3 (municipality of Apuí and other municipalities on the Madeira River and affluent). It was concluded that N. caninum is present with high seroprevalence values, when compared to other cattle producing states in the Amazon region of Brazil. The identified factors can be used as risk indicators so that control measures can be implemented to prevent infection by N. caninum in these herds.


Assuntos
Anticorpos Antiprotozoários , Doenças dos Bovinos , Coccidiose , Neospora , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Coccidiose/veterinária , Fatores de Risco , Estudos Soroepidemiológicos
5.
Rev Bras Parasitol Vet ; 29(3): e008820, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33027425

RESUMO

Dogs are hosts of the protozoans Toxoplasma gondii, which causes an important public health disease, and Neospora caninum. Studies that have evaluated toxoplasmosis and neosporosis for prolonged periods in dog populations are rare. We analyzed infection by both parasites in a domestic dog population over three consecutive years in São Paulo state, Brazil. In the 1st, 2nd and 3rd years of collection, 181, 193 and 172 domiciles were visited, and blood samples of 331, 371 and 348 dogs were collected for antibody serology, respectively. The seroprevalence of T. gondii in each year was 27.2%, 22.5% and 43.9%, respectively, and that of N. caninum was 7.8%, 4.8% and 6.8%, respectively. The incidence rates for T. gondii in the 2nd and 3rd collections were 13.2% and 30.0%, and those for N. caninum were 3.3% and 4.4%, respectively. Positive and negative serological conversions for both agents occurred at high frequencies during the study period. This study reveals the canine population's serological profile and demonstrates the constant exposure of dogs to the investigated pathogens, indicating the need for prevention and control measures in the region.


Assuntos
Coccidiose , Doenças do Cão , Neospora , Toxoplasma , Toxoplasmose Animal , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Coccidiose/sangue , Coccidiose/epidemiologia , Coccidiose/parasitologia , Coccidiose/veterinária , Doenças do Cão/epidemiologia , Cães , Incidência , População Rural , Estudos Soroepidemiológicos , Toxoplasmose Animal/sangue , Toxoplasmose Animal/epidemiologia
6.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1381-1385, July-Aug. 2020. ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1131482

RESUMO

O abortamento na espécie equina é responsável por grandes perdas econômicas e, entre as possíveis causas, está a neosporose, uma enfermidade que nem sempre é investigada como provável diagnóstico. Assim, o objetivo deste trabalho foi relatar um caso de aborto equino aos 129 dias de gestação, resultante da infecção por Neospora spp.. Amostras sanguíneas da égua e do feto abortado foram enviadas para um laboratório especializado. À necrópsia, constatou-se edema gelatinoso e hemorrágico em subcutâneo, fígado ictérico e friável com autólise de alguns órgãos, como baço, rins e glândulas adrenais. Fragmentos dos órgãos coletados na necrópsia foram submetidos à histopatologia e à pesquisa de agentes infecciosos, em que se identificou hepatite e epicardite não purulentas e onfalite purulenta, bem como exame positivo para Neospora spp. pela técnica de reação em cadeia da polimerase (PCR) convencional e Nested. O soro sanguíneo obtido da égua foi submetido à pesquisa de Neospora spp. pela técnica de imunofluorescência indireta, de herpesvírus por soroneutralização em cultura de células e de Leptospira sp. por PCR, todas com resultados negativos. Dessa forma, é importante considerar a neosporose como diagnóstico diferencial em casos de abortamento e natimortalidade, uma vez que a presença de cães nas propriedades é extremamente comum, representando uma importante fonte de infecção.(AU)


Abortion in the equine species is responsible for major economic losses, and among the possible causes is neosporosis, a disease that is not always investigated as a probable diagnosis. Thus, the objective of this study was to report an abortion at 129 days of gestation resulting from Neospora spp. Blood samples from the mare and the aborted fetus were sent to a specialized laboratory. Under necropsy, gelatinous and hemorrhagic edema was detected in subcutaneous tissue, friable and jaundiced liver with autolysis in spleen, kidneys and adrenal glands. Fragments of the organs collected at necropsy were submitted to histopathology and infectious agent tests, which identified non-purulent hepatitis and epicarditis and purulent omphalitis. Also, a positive result for Neospora spp. by the conventional and nested Polymerase Chain Reaction (PCR) technique. Blood serum obtained from the mare was subjected to analyses to Neospora spp. by indirect immunofluorescence technique, herpesvirus by serum neutralization in cell culture and Leptospira sp. by PCR, all with negative results. Thus, it is important to consider neosporosis as a differential diagnosis in cases of abortion and stillbirth, since the presence of dogs in the properties is extremely common and represent an important source of infection.(AU)


Assuntos
Animais , Feminino , Neospora/isolamento & purificação , Aborto Animal/diagnóstico , Feto Abortado/microbiologia , Cavalos/microbiologia , Reação em Cadeia da Polimerase/veterinária
7.
Exp Parasitol ; 216: 107942, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32598889

RESUMO

The intracellular protozoan parasite Neospora caninum is incriminated to induce drastic economic losses in both livestock and pet animal industries. Neosporosis is primarily characterized by abortion in cattle and paralytic symptoms in dogs. Because there are no effective treatments or vaccines, diagnosis is critical for Neospora control. Thus, diversification of laboratory tests and specimens used for diagnosis of N. caninum is an essential scientific endeavor to judge and select the most appropriate diagnostic tool. Herein, we provide the first evidence for the utility of urine samples for demonstration of specific antibodies against N. caninum employing an experimentally infected murine model. Specific antibodies to recombinant N. caninum dense granule 7, surface antigen 1, and lysate antigen were assayed using different antibodies-based ELISAs. Urine based IgG ELISA efficiently discriminated between infected mice (acute or chronic infection), and those of non-infected mice. This effect was also noticed for IgG1 and IgG2a suggesting the utility of urine for assessment of T-helper 2- and T-helper 1-mediated immunities, respectively. In addition, reactivity of specific antibody in urine was also confirmed against parasites when indirect fluorescent antibody test was employed. Usefulness of urine as an additional clinical sample for Neospora diagnosis was confirmed via comparison with the relevant control non-infected and infected mouse sera as reference samples. Because of minimum invasiveness and ease of urine collection, this approach might offer new diagnostic opportunities for N. caninum either for the field or research purposes. However, further studies are required to extrapolate this preliminary study and results in the animal species of interest particularly in dogs.


Assuntos
Anticorpos Antiprotozoários/urina , Coccidiose/diagnóstico , Neospora/imunologia , Análise de Variância , Animais , Anticorpos Antiprotozoários/sangue , Chlorocebus aethiops , Coccidiose/imunologia , Coccidiose/parasitologia , Ensaio de Imunoadsorção Enzimática , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Imunoglobulina G/sangue , Imunoglobulina G/urina , Imunoglobulina M/sangue , Imunoglobulina M/urina , Camundongos , Camundongos Endogâmicos BALB C , Neospora/isolamento & purificação , Células Vero
8.
Rev Bras Parasitol Vet ; 29(2): e016019, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32520089

RESUMO

A cross-sectional study was carried out on a sample of 379 horses to determine the seroprevalence of Neospora spp. in Jordan using the indirect fluorescent antibody test. Five variables, namely locality (n=10), climatic zone (n=4), age group (n=3), gender, and breed were tested as risk factors for Neospora-immunoglobulin (Ig)G seropositivity at four cutoff titers (1:50, 1:200, 1:400, and 1:800) using univariate and multivariate logistic regression analyses. A total of 122 (32%; 95% CI: 28, 37) sera samples had anti-Neospora-IgG at a cutoff titer of 1:50. Increased Neospora-IgG seropositivity was found in horses in three localities (Madaba, Zarka, and Petra) and was associated with the following variables: cool temperate climate; age >14 years; and female gender. Seropositivity was found among horses from Madaba at all cutoff titers, Zarka at titers >1:200, and Petra at titers <1:200. Cool temperate climate was associated with titers <1:400. Horses aged >14 years were found to be associated with seropositivity at titers ≥1:200. Female gender was associated with high seropositivity at >1:800.


Assuntos
Anticorpos Antiprotozoários/sangue , Coccidiose/veterinária , Doenças dos Cavalos/epidemiologia , Neospora/imunologia , Fatores Etários , Animais , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Estudos Transversais , Feminino , Doenças dos Cavalos/diagnóstico , Cavalos , Jordânia/epidemiologia , Masculino , Fatores de Risco , Estudos Soroepidemiológicos , Fatores Sexuais
9.
Aust Vet J ; 98(8): 380-387, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32350856

RESUMO

OBJECTIVE: The aim of this study was to utilise wild rabbits (Oryctolagus cuniculus) as a sentinel species to study levels of environmental contamination with N. caninum and T. gondii in South Australia, and to examine associations with rainfall, climate and land use. DESIGN: Toxoplasma gondii (T. gondii), an apicomplexan parasite, causes the clinical disease toxoplasmosis, which can affect sheep as well as humans and many other animals. Neosporosis, the clinical disease caused by closely related Neospora caninum (N. caninum), causes abortions in cattle, with large economic impacts to cattle industries. METHODS: Aliquots of wild rabbit (Oryctolagus cuniculus) serum were obtained from twelve sites across South Australia over a period of eighteen years, with a total of 2114 samples. An in-house Modified Agglutination Test (MAT) was developed, and samples were screened for the specific antibodies against both T.gondii and N. caninum. RESULTS: Overall, 9.9% of samples screened for T. gondii tested positive and 6.1% of samples screened for N. caninum tested positive. There was no difference observed in seroprevalence of T.gondii specific antibodies between samples collected throughout summer, autumn, winter or spring. By contrast, a significantly higher (p=0.030) seroprevalence of N. caninum specific antibodies was observed in spring than any other season. T. gondii and N. caninum antibodies were discovered at sites across a broad area of South Australia, indicating these environments maybe infected with both parasites. CONCLUSION: Results provide evidence that suggests N. caninum oocysts may have different survival characteristics, such as varying tolerances to low relative humidity, than T. gondii oocysts.


Assuntos
Doenças dos Bovinos , Coccidiose/veterinária , Neospora/imunologia , Doenças dos Ovinos , Toxoplasma/imunologia , Toxoplasmose Animal , Aborto Animal , Animais , Anticorpos Antiprotozoários , Bovinos , Feminino , Humanos , Gravidez , Coelhos , Espécies Sentinelas , Estudos Soroepidemiológicos , Ovinos , Austrália do Sul
10.
Sci Rep ; 10(1): 7483, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32366934

RESUMO

Neospora caninum is an Apicomplexan parasite related to important losses in livestock, causing abortions and decreased fertility in affected cows. Several chemotherapeutic strategies have been developed for disease control; however, no commercial treatment is available. Among the candidate drugs against neosporosis, phenothiazinium dyes, offer a low cost-efficient approach to parasite control. We report the anti-parasitic effects of the phenothiaziums Methylene Blue (MB), New Methylene Blue (NMB), 1,9-Dimethyl Methylene Blue (DMMB) and Toluidine Blue O (TBO) on N. caninum, using in vitro and in vivo models. The dyes inhibited parasite proliferation at nanomolar concentrations (0.019-1.83 µM) and a synergistic effect was achieved when Methylene Blue was combined with New Methylene Blue (Combination Index = 0.84). Moreover, the phenothiazinium dyes improved parasite clearance when combined with Pyrimethamine (Pyr). Combination of Methylene Blue + 1,9-Dimethyl Methylene Blue demonstrated superior efficacy compared to Pyrimethamine based counterparts in an in vivo model of infection. We also observed that Methylene Blue, New Methylene Blue and 1,9-Dimethyl Methylene Blue increased by 5000% the reactive oxygen species (ROS) levels in N. caninum tachyzoites. Phenothiazinium dyes represent an accessible group of candidates with the potential to compound future formulations for neosporosis control.


Assuntos
Coccidiose , Azul de Metileno/análogos & derivados , Neospora/crescimento & desenvolvimento , Animais , Chlorocebus aethiops , Coccidiose/tratamento farmacológico , Coccidiose/metabolismo , Masculino , Azul de Metileno/farmacologia , Camundongos , Células Vero
11.
Pesqui. vet. bras ; 40(5): 325-332, May 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1135637

RESUMO

A case series study was conducted to determine the frequency of causes of abortion in dairy cattle in Uruguay. The sample size of 102 cases was composed of 53 fetuses, 35 fetuses with placentas, and 14 placentas without an associated fetus. All cases underwent gross and microscopic pathologic examinations as well as microbiological and serological testing. The etiology was determined in 54 (53%) of cases, 51 of which were caused by infectious agents. Within the observed 102 cases, 30 (29%) were caused by Neospora caninum, six (6%) by Coxiella burnetii and two (2%) by Campylobacter fetus subsp. venerealis. Bovine Parainfluenza-3 virus and Salmonella enterica serovar Newport caused one abortion each. Opportunistic bacteria (Escherichia coli, Streptococcus sp., Staphylococcus sp., Mannheimia sp., Trueperella pyogenes, and Providencia stuartii) were associated with 11 abortions. In two cases the fetal death was attributed to dystocia, and in one case the fetus had a congenital mesothelioma. Bovine viral diarrhea virus (BVDV) infection was identified in three fetuses; two of which were co-infected with and had typical lesions of N. caninum. No lesions were observed in the other fetus infected by BVDV. Leptospira interrogans was identified in one fetus without lesions. Despite the relatively low overall success rate in establishing an etiological diagnosis in cases of abortion in cattle, a systemic workup of bovine abortion is necessary to establish prevention and control strategies. This also facilitates monitoring and surveillance of reproductive diseases in dairy cattle, some of which represent a risk to public health.(AU)


Uma série de casos foi estudada para determinar a frequência de causas do aborto em bovinos leiteiros no Uruguai. A amostra, de 102 casos, foi composta por 53 fetos, 35 fetos com placentas e 14 placentas sem feto associado. Todos os casos foram submetidos a exames patológicos macroscópicos e microscópicos, além de testes microbiológicos e sorológicos. A etiologia foi determinada em 54 (53%) dos casos, 51 dos quais foram causados por agentes infecciosos. Nos 102 casos observados, 30 (29%) foram causados por Neospora caninum, seis (6%) por Coxiella burnetii e dois (2%) por Campylobacter fetus subsp. venerealis. O vírus da Parainfluenza-3 e Salmonella enterica serovar Newport causaram um aborto cada. Bactérias oportunistas (Escherichia coli, Streptococcus sp., Staphylococcus sp., Mannheimia sp., Trueperella pyogenes e Providencia stuartii) foram associadas a 11 abortos. Em dois casos, a morte fetal foi atribuída a distocia e, em um caso, o feto apresentava mesotelioma congênito. A infecção pelo vírus da diarreia viral bovina (BVDV) foi identificada em três fetos; dois dos quais foram co-infectados e apresentavam lesões típicas de N. caninum. Não foram observadas lesões no outro feto infectado pelo BVDV. Leptospira interrogans foi identificada em um feto sem lesões. Apesar da relativamente baixa taxa de sucesso no diagnóstico etiológico nos casos de aborto em bovinos, é necessário o diagnóstico sistemático dos abortos para estabelecer estratégias de prevenção e controle. Isso também facilita o monitoramento e a vigilância de doenças reprodutivas em bovinos leiteiros, algumas das quais representam um risco para a saúde pública.(AU)


Assuntos
Animais , Feminino , Gravidez , Bovinos , Campylobacter fetus , Infecções por Campylobacter/veterinária , Coxiella burnetii , Coccidiose/veterinária , Neospora , Aborto Animal/etiologia , Aborto Animal/patologia , Uruguai , Leptospira , Leptospirose/veterinária
12.
J Vet Diagn Invest ; 32(3): 401-408, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32306865

RESUMO

Neospora caninum is a protozoan parasite that causes abortion and important economic losses in cattle worldwide. There are no treatments or vaccines available; disease control is based on diagnosis and herd management strategies. We developed, validated, and evaluated under field conditions a competitive inhibition ELISA based on the truncated SAG1 protein (tSAG1), expressed in Escherichia coli, and the RafNeo5 monoclonal antibody (ciELISAtSAG1). A criterion based on the 3-y sequential serologic analysis of 230 dairy cows by IFAT was used as the gold standard. The assay was validated using 860 serum samples from cows that were consistently positive or negative by IFAT throughout the study period. ciELISAtSAG1 was then used to evaluate the prevalence of neosporosis in 16 beef cow herds (22 samples per herd, 352 total samples). The results were compared with those from IFAT and a commercial cELISA (cELISAVMRD). The ciELISAtSAG1 cutoff was ≥ 29%I, with a diagnostic sensitivity of 98.7% (95% CI = 96.8-99.7%) and a diagnostic specificity of 97.9% (95% CI = 96.4-99.0%). Concordance among IFAT, cELISAVMRD, and ciELISAtSAG1 was 90.3%. The agreement (κ) between ciELISAtSAG1 and the other 2 tests was ≥ 0.81. The overall prevalence of neosporosis in the 16 beef herds was 30% (range: 5-60%). The ciELISAtSAG1 could be useful for large-scale detection of anti-N. caninum antibodies in cattle and seroepidemiologic investigations, given its appropriate sensitivity and specificity, and the simplicity of production.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças dos Bovinos/diagnóstico , Coccidiose/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Neospora/isolamento & purificação , Proteínas de Protozoários/análise , Proteínas Recombinantes/análise , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/diagnóstico , Coccidiose/parasitologia , Ensaio de Imunoadsorção Enzimática/métodos
13.
Vet Parasitol ; 281: 109101, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32302944

RESUMO

Neosporosis is caused by infection with the protozoa Neospora caninum. It manifests as various neurological symptoms and is considered as one of the main causes of abortion in cattle, and induces uncommon congenital infection in sheep. The standard diagnosis is based on indirect immunofluorescence (IFI); however, cross-reactivity with other protozoa proteins is common. Aiming a more specific diagnosis, recombinant antigens have been tested in several immunoassays; of these, NcSAG1 (surface antigen-1) and NcSRS2 (SAG1-related sequence 2) were the most promising. In this context, we developed an indirect ELISA with recombinant NcSRS2 (ELISA-rNcSRS2) and NcSAG1 (ELISA-rNcSAG1) proteins alone and in association (ELISA-rNcSRS2/rNcSAG1) for the diagnosis of cattle and ovine neosporosis. A total of 216 samples from cattle and 154 samples from sheep were used to evaluate the ELISAs. The sensitivity and specificity results of the ELISA-rNcSRS2 were 91.5 % and 96.4 % for cattle, and 89.6 % and 96.3 % for sheep, respectively. For the ELISA-rNcSAG1, the sensitivity and specificity were 84.9 % and 97.3 % for cattle, and 89.6 % and 92.6 % for sheep, respectively. The sensitivity and specificity of the ELISA-rNcSRS2/rNcSAG1 was 98.1 % and 99.1 % for cattle, 100 % and 97.2 % for sheep, respectively. These results indicated that indirect ELISA using the rNcSRS2 and rNcSAG1 proteins are a highly sensitive and specific method, especially when used in association, for detecting antibodies in cattle and ovine populations infected with N. caninum.


Assuntos
Coccidiose/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Neospora/imunologia , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Coccidiose/diagnóstico , Técnica Indireta de Fluorescência para Anticorpo , Neospora/genética , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/diagnóstico
14.
J Parasitol ; 106(2): 312-315, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32330280

RESUMO

The purpose of this study was to describe the prevalence and incidence of Neospora caninum infection in dogs that are in close contact with dairy cattle and to identify possible risk factors associated with the infection in this population. Twenty-four dogs located in 8 different dairy farms of Aguascalientes, Mexico, were evaluated for a 6-mo period. Once a month a sample of serum and a sample of peripheral blood was collected. The serum was used to detect antibodies against N. caninum by means of the indirect immunofluorescence technique, and the blood was used to detect parasite's DNA. The association between seroprevalence and possible risk factors was estimated using logistic regression. The prevalence of anti-N. caninum antibodies was 54% in the first month, 62% in the last month, and the incidence was 8.69%. One farm had no positive cases. Antibody titers ranged from 1:50 to 1:800. Parasite DNA was not detected in any of the samples. Only the age (>6 yr) of the dogs was identified as a risk factor for infection by N. caninum (P ≤ 0.05).


Assuntos
Coccidiose/veterinária , Doenças do Cão/parasitologia , Neospora , Fatores Etários , Animais , Anticorpos Antiprotozoários/sangue , Bovinos , Coccidiose/epidemiologia , Coccidiose/parasitologia , DNA de Protozoário/sangue , DNA de Protozoário/isolamento & purificação , Indústria de Laticínios , Doenças do Cão/epidemiologia , Cães , Feminino , Incidência , Masculino , México/epidemiologia , Neospora/genética , Neospora/imunologia , Prevalência , Fatores de Risco
15.
Rev Bras Parasitol Vet ; 29(1): e019119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32236334

RESUMO

Serological screening of 199 serum samples from Dromedary camels-from different cities in Saudi Arabia-was performed using enzyme-linked immunosorbent assay for detecting antibodies against two cyst-forming coccidian parasites, namely Toxoplasma gondii and Neospora caninum. Antibodies against T. gondii were detected in 68 (34.2%) samples, while those against N. caninum were present in 33 (16.6%) samples. The highest seroprevalence of T. gondii antibodies was reported in samples from Taif (51.2%), while the lowest seroprevalence was reported in samples from Riyadh and Hofuf (15.1%). The highest seroprevalence of N. caninum antibodies was reported in samples from Jizan (35.9%) while the lowest was reported in samples from Taif (2.4%). A total of 47 male and 21 female camels exhibited antibodies against T. gondii , while 19 male and 14 female camels showed antibodies against N. caninum . Concurrent detection of both T. gondii and N. caninum antibodies was observed in 18 camels. It has been demonstrated that T. gondii and N. caninum antibodies are prevalent in camels from different cities of the Kingdom of Saudi Arabia.


Assuntos
Anticorpos Antiprotozoários/sangue , Camelus/parasitologia , Coccidiose/veterinária , Neospora/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Animais , Coccidiose/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Masculino , Arábia Saudita/epidemiologia , Estudos Soroepidemiológicos , Toxoplasmose Animal/diagnóstico
16.
Parasitol Res ; 119(4): 1353-1362, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32157394

RESUMO

Recent studies have revealed extensive genetic variations among Neospora caninum, a cyst-forming protozoan parasite that is one of the main causes of bovine abortion in the cattle industry worldwide. Previous genetic studies based on multilocus microsatellite genotyping (MLGs) of different Ibero-American populations showed a high genetic diversity. These studies provided clear clues of a predominant clonal propagation in cattle and population sub-structuring partially associated with geographical origin. Although, these reports were limited to a reduced number of countries. In this study, the N. caninum isolates from aborted bovine fetuses and stillbirths and a goat abortion from Northern Italy were investigated genetically using 9 microsatellite markers. Complete or nearly complete isolate profiles were obtained from 30 fetuses and stillbirths. An extensive genetic diversity was also found in this Italian N. caninum population. The study of genetic relationships among Italian MLGs using network (eBURST) and principal component analyses based on the allele-sharing coefficient (PCoA) showed different clonal subpopulations disseminated throughout Northern Italy without apparent segregation depending on the geographic origin, cattle breed, or time of collection. The presence of linkage disequilibrium supports a predominant clonal propagation of Italian N. caninum. In addition, most of Italian MLGs segregated from other global populations including Spain, Argentina, Mexico, Brazil, Germany, and Scotland, suggesting the existence of specific N. caninum subpopulations in the Northern Italy and different subpopulations of N. caninum circulating in Europe.


Assuntos
Aborto Animal/parasitologia , Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Neospora/genética , Feto Abortado/parasitologia , Animais , Bovinos , Feminino , Feto/parasitologia , Variação Genética/genética , Geografia , Cabras/genética , Itália , Desequilíbrio de Ligação/genética , Repetições de Microssatélites/genética , Neospora/classificação , Neospora/isolamento & purificação , Gravidez
17.
Vet Parasitol ; 280: 109091, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32208305

RESUMO

Neospora caninum is considered one of the main causes of abortion in cattle but can also cause abortion in sheep. There is limited knowledge of the N. caninum population infecting sheep, and only one N. caninum isolate from a pregnant sheep from Japan has been reported. This study describes the in vitro isolation and genetic characterization of two new sheep isolates of N. caninum implicated in ovine reproductive failure. We used IFN-γ-knockout mice inoculated with PCR-positive brain homogenates from two clinically healthy but congenitally infected lambs at 4.5 months of age for parasite isolation. The lambs were born to dams from a sheep farm that had experienced pregnancy failure caused by N. caninum in successive generations. Tachyzoites were microscopically visualized in peritoneal flushes from all inoculated mice and were also observed in MARC-145 cell cultures within one week after inoculation with peritoneal flushes. Two N. caninum isolates, Nc-Spain11 and Nc-Spain12, were obtained from each lamb. The genotyping of the Nc-Spain11 and Nc-Spain12 isolates based on 9 microsatellite markers showed identical multilocus genotype (MLG). Comparison between a previous N. caninum genotype dataset including 80 MLGs from Argentinean, Spanish, Mexican, German and Scottish bovine isolates and the Japanese sheep isolate showed that the Nc-Spain11 and Nc-Spain12 MLG was unique and differed from the other MLGs. eBURST analyses showed that the Nc-Spain11 and Nc-Spain12 MLG was genetically clustered with other bovine MLGs and one ovine MLG, and the nearest genetic relationship was with an MLG from a bovine abortion collected in the same geographical area of Galicia.


Assuntos
Coccidiose/veterinária , Neospora/isolamento & purificação , Doenças dos Ovinos/parasitologia , Animais , Coccidiose/parasitologia , Feminino , Interferons/deficiência , Masculino , Camundongos , Camundongos Knockout/parasitologia , Neospora/genética , Análise de Sequência de DNA/veterinária , Ovinos , Espanha
18.
Prev Vet Med ; 176: 104913, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32066027

RESUMO

Neospora caninum is an apicomplexan parasite with worldwide distribution, which primarily causes disease in dogs and cattle. It has been recognized as an important cause of epidemic and endemic abortion in cattle around the world. There is no study to demonstrate the country level picture of the disease in Iran and estimate the extent of the problem, quantitatively. Therefore, the aim of the present study was to systematically review the observational studies on bovine neosporosis in Iran and estimate an overall serologic prevalence of the infection in the cattle population. Search for all published reports on N. caninum in Iran was conducted from inception until September 2018. Major English (PubMed, Scopus and Science Direct) and Persian (IranDoc, SID, Iranmedex, and Magiran) electronic database sources were used for this study. After removing duplicated articles, 128 documents remained. Unrelated articles (89) were excluded after primary screening and 39 articles were evaluated for eligibility. Finally, 37 studies from 33 articles were recognized as eligible and were included in the present work. The author screened the studies and extracted the data twice, carefully. Based on the meta-analysis, the overall serologic prevalence of N. caninum in 10,967 cattle with 2619 positive ones was 23.6 % with 95 % CI: 19.8-27.9 %. The random effect model was used for meta-analysis because the Cochran Q value (795.10, df = 36, P < 0.001) and Higgins index (I2 = 95.47 %) showed statistically significant heterogeneity. In subgroup meta-analysis, abortion status of the animal and geographical location of the study showed significant association with serologic prevalence, while age and breed did not have significant associations. No publication bias was detected, and sensitivity analysis showed stability of the overall estimate after excluding any individual study. It could be concluded that N. caninum is widespread in cattle population in Iran and the time is right to implement national level educational and control programs for it.


Assuntos
Doenças dos Bovinos/epidemiologia , Coccidiose/veterinária , Neospora/fisiologia , Animais , Bovinos , Doenças dos Bovinos/virologia , Coccidiose/epidemiologia , Coccidiose/virologia , Feminino , Irã (Geográfico)/epidemiologia , Prevalência , Estudos Soroepidemiológicos
19.
Parasit Vectors ; 13(1): 85, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32070415

RESUMO

BACKGROUND: Lipid metabolism is pivotal for the growth of apicomplexan parasites. Lipid synthesis requires bulk carbon skeleton acyl-CoAs, the transport of which depends on the acyl-CoA binding protein (ACBP). In Neospora caninum, the causative agent of neosporosis, the FASII pathway is required for growth and pathogenicity. However, little is known about the fatty acid transport mechanism in N. caninum. METHODS: We have identified a cytosolic acyl-CoA binding protein, with highly conserved amino acid residues and a typical acyl-CoA binding domain in N. caninum. The recombinant NcACBP protein was expressed to verify the binding activities of NcACBP in vitro, and the heterologous expression of NcACBP in Δacbp yeast in vivo. Lipid extraction from ΔNcACBP or the wild-type of N. caninum was analyzed by GC-MS or TLC. Furthermore, transcriptome analysis was performed to compare the gene expression in different strains. RESULTS: The NcACBP recombinant protein was able to specifically bind acyl-CoA esters in vitro. A yeast complementation assay showed that heterologous expression of NcACBP rescued the phenotypic defects in Δacbp yeast, indicating of the binding activity of NcACBP in vivo. The disruption of NcACBP did not perturb the parasite's growth but enhanced its pathogenicity in mice. The lipidomic analysis showed that disruption of NcACBP caused no obvious changes in the overall abundance and turnover of fatty acids while knockout resulted in the accumulation of triacylglycerol. Transcriptional analysis of ACBP-deficient parasites revealed differentially expressed genes involved in a wide range of biological processes such as lipid metabolism, posttranslational modification, and membrane biogenesis. CONCLUSIONS: Our study demonstrated that genetic ablation of NcACBP did not impair the survival and growth phenotype of N. caninum but enhanced its pathogenicity in mice. This deletion did not affect the overall fatty acid composition but modified the abundance of TAG. The loss of NcACBP resulted in global changes in the expression of multiple genes. This study provides a foundation for elucidating the molecular mechanism of lipid metabolism in N. caninum.


Assuntos
Inibidor da Ligação a Diazepam/metabolismo , Ácidos Graxos/metabolismo , Neospora/genética , Neospora/metabolismo , Proteínas de Protozoários/metabolismo , Animais , Inibidor da Ligação a Diazepam/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Feminino , Perfilação da Expressão Gênica , Metabolismo dos Lipídeos , Camundongos , Camundongos Endogâmicos BALB C , Neospora/patogenicidade , Ligação Proteica , Proteínas de Protozoários/genética , Proteínas Recombinantes/metabolismo , Virulência
20.
Vet Clin North Am Food Anim Pract ; 36(1): 205-222, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029185

RESUMO

Neospora caninum, Toxoplasma gondii, and Sarcocystis spp. are related Apicomplexan parasites that have 2 hosts in their life cycles. The definitive hosts excrete unsporulated (Neospora caninum, T gondii) or sporulated (Sarcocystis spp.) oocysts in their feces after ingesting tissue cysts from the tissues of ruminant intermediate hosts. These coccidians can cause abortion and neonatal mortality in ruminants. T gondii and Sarcocystis hominis (from cattle) are zoonotic. This article reviews information on the etiology, life cycle, diagnosis, control and prevention of these parasites and the diseases they cause in ruminants.


Assuntos
Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Doenças das Cabras/parasitologia , Sarcocistose/veterinária , Doenças dos Ovinos/parasitologia , Animais , Bovinos , Cabras , Neospora/isolamento & purificação , Ruminantes/parasitologia , Ovinos , Toxoplasma/isolamento & purificação , Toxoplasmose Animal
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