Avaliação comparativa das técnicas de ELISA indireto, antígeno acidificado tamponado, 2-mercaptoetanol com soroaglutinação lenta e fixação de complemento para o diagnóstico da brucelose em rebanho bovino não vacinado, rebanho vacinado com dose padrão e rebanho vacinado com dose reduzida da amostra 19 de Brucella abortus

Pós-graduação em Medicina Veterinária - FMVZ

Desenvolvimento e aplicação do ELISA indireto com proteína recombinante de nucleocapsídeo de coronavírus felino (FCoV) para quantificação de anticorpos em soros de gatos naturalmente infectados

Pós-graduação em Medicina Veterinária - FMVZ

Development of a peptide ELISA for the diagnosis of Equine arteritis virus

A peptide-based indirect ELISA was developed to detect antibodies against Equine arteritis virus (EAV). Two peptides for epitope C of protein GP5 and fragment E of protein M were designed, synthesized, purified and used as antigens either alone or combined. Ninety-two serum samples obtained from the 2010 Equine viral arteritis outbreak, analyzed previously by virus neutralization, were evaluated by the ELISA here developed. The best resolution was obtained using peptide GP5. The analysis of the inter- and intraplate variability showed that the assay was robust. The results allow concluding that this peptide-based ELISA is a good alternative to the OIE-prescribed virus neutralization test because it can be standardized between laboratories, can serve as rapid screening, can improve the speed of diagnosis of EAV-negative horses and can be particularly useful for routine surveillance in large populations. (C) 2014 Elsevier B.V. All rights reserved.

Desenvolvimento e aplicação do Elisa indireto com a nucleoproteína recombinante (NPR) do vírus da doença de Newcastle

Pós-graduação em Medicina Veterinária - FCAV

Subclinical diagnosis of Caseous lymphadenitis based on Elisa in Sheep from Brazil

Caseous lymphadenitis (CLA), caused by Corynebacterium pseudotuberculosis, is a chronic contagious disease that affects small ruminants and still remains an important problem for many lamb-producing countries. Animals are considered clinically infected when occurs abscesses in superficial lymph nodes. Visceral or internal form can coexist which no apparent clinical signs of infection are seen. The best procedure to avoid spread of the disease is elimination of infected animals. However, as the chronic and subclinical nature of the infection of CLA alternative methods are required for detection and screening. In this study, we described the performance of indirect Enzyme-Linked Immunosorbent Assay (ELISA) for diagnosis of CLA in asymptomatics sheep. Also, test culture and biochemical identification were achieved to confirm CLA infection. The serological diagnostic was performed in sheep symptomatics (n=50) and asymptomatics (n=374) from nine flocks. Analysis reported high positivity of 71% for ELISA in 85% of asymptomatic animal for CLA with a sensitivity of 88% and specificity of 31%. Results from ELISA test in asymptomatic animals against culture for caseous lymphadenitis were more specific (97%) and permitted to exclude healthy animals without symptoms. This study concluded that C. pseudotuberculosis infection could be widely disseminated in sheep flocks in Northwestern region of the state of São Paulo, Brazil and only one screening test is not enough. The association with indirect ELISA test and culture could better indicate the real problem of CLA in sheep flocks.

Ocorrência da diarréia viral bovina nas regiões sul do Estado de Minas Gerais e nordeste do Estado de São Paulo

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

Humoral immune response of water buffalo monitored with three different antigens of Toxocara vitulorum

Humoral immune response of water buffalo naturally infected with Toxocara vitulorum was monitored using three different antigens of this parasite in serum and colostrum of buffalo cows and calves. Soluble extract (Ex) and excretory/secretory (ES) larval antigens and perienteric fluid antigen (Pe) of adult T vitulorum were used to measure the antibody levels by an indirect ELISA. Serum of 7-12 buffalo cows for the first 365 days and colostrum of the same number of buffalo cows for the first 60 days of parturition, and serum of 8-10 buffalo calves for the first 365 days afterbirth were assayed. The ELISA detected antibodies against all three T vitulorum antigens in the colostrum and serum of 100% of buffalo cows and calves examined. The highest antibody levels against Ex, ES and Pe antigens were detected in the buffalo cow sera during the perinatal period and were maintained at high levels through 300 days after parturition. on the other hand, colostrum antibody concentrations of all three antigens were highest on the first day post-parturition, but decreased sharply during the first 15 days. Concomitantly to the monitoring of immune response, the parasitic status of the calves was also evaluated. In calves, antibodies passively acquired were at the highest concentrations 24 h after birth and remained at high levels until 45 days coincidentally with the peak of T vitulorum infection. The rejection of the worms by the calves occurred simultaneously with the decline of antibody levels, which reached their lowest levels between 76 and 150 days. Thereafter, probably because of the presence of adults/larvae stimulation, the calves acquired active immunity and the antibodies started to increase slightly in the serum and plateaued between the days 211 and 365. All three antigens were detected by the serum antibodies of buffalo calves; however, the concentration of anti-Pe antibody was higher than anti-EX and anti-ES, particularly after 90 days of age. By conclusion, the buffalo cows develop immunity and keep high levels of antibodies against T vitulorum-Ex, ES and Pe antigens and these antibodies are transferred to their calves through the colostrum. This passively acquired immunity does not protect the calves against the acquisition of the infection, but these antibodies, passively or actively acquired, may have an important role during worm rejection by the calves and prevention of intestinal reinfection. (C) 2004 Elsevier B.V. All rights reserved.

Resposta humoral de bovinos vacinados contra as toxinas botulínicas tipos C e D em diferentes faixas etárias

Foi verificada pelo teste de ELISA indireto a resposta humoral contra os toxoides botulínicos C e D em bovinos de diferentes idades. O estudo envolveu 90 animais, que foram divididos em três grupos (n = 30), de acordo com a sua faixa etária; inferior a 2 anos de idade (G1), entre 2 e 5 anos (G2) e superior a 5 anos (G3). Os grupos experimentais foram vacinados com duas doses de vacina antibotulínica bivalente (C e D) comercial, nos dias 0 e 42 após a primo-vacinação (booster). Na avaliação, quando realizada 30 dias após o booster, os animais do G3 apresentaram maior produção de anticorpos (p < 0,05) em relação aos demais grupos. Entre o G1 e G2 não houve diferença significativa na resposta humoral contra a toxina C, no entanto, contra a toxina D, os animais do G1 apresentaram maior produção de anticorpos. Todos os grupos produziram uma resposta significativa de anticorpos contra as toxinas botulínicas após a 2ª dose da vacina bivalente comercial, principalmente contra o tipo D.

Diagnóstico sorológico da brucelose bovina em animais adultos vacinados com dose reduzida da cepa 19 de Brucella abortus

Com o presente trabalho avaliou-se o uso de dose reduzida da vacina produzida com a amostra 19 de Brucella abortus, em rebanho adulto negativo para a enfermidade, por meio de técnicas de diagnóstico sorológico preconizadas pelo Programa Nacional de Controle e Erradicação da Brucelose e Tuberculose Animal e por um ensaio indireto de imunoadsorção enzimática (ELISA ID). A prova de fixação de complemento detectou 46,77% de positivos, o antígeno acidificado tamponado 67,74%, o 2-mercaptoetanol com soroaglutinação lenta 87,09% e o ELISA ID 100%. A dose reduzida interferiu no diagnóstico sorológico. Nenhuma das técnicas apresentou especificidade adequada para uso em rebanho nestas condições, até 3 meses após a vacinação.

Animal cysticercosis in indigenous Brazilian villages

A inspeção sanitária da carne bovina e suína tem sido a principal forma diagnóstica da cisticercose animal e da prevenção da teníase no Brasil. As aldeias indígenas Jaguapirú e Bororó estão localizadas próximo à área urbana do município de Dourados-MS, com condições precárias de saneamento básico, onde bovinos e suínos são criados como fonte de alimento para consumo próprio, bem como para comercialização externa, geralmente sem inspeção sanitária oficial. Neste estudo, 96 carcaças bovinas e 117 amostras de soro de suínos, criados nas aldeias indígenas, foram avaliadas para a presença de formas metacestóides à inspeção sanitária e de anticorpos anti-Taenia sp. ao teste ELISA, respectivamente. Observaram-se 18,75% de positividade para cisticercose bovina e 9,4% para cisticercose suína. A ocorrência do complexo teníase-cisticercose nas aldeias pode favorecer a ocorrência desta zoonose na população indígena. Condições adequadas de abate e inspeção sanitária dos animais destas aldeias se fazem urgente para o controle do complexo teníase-cisticercose na população indígena.

Teste imunoenzimático (enzyme-linked immunosorbent assay) para diagnóstico da cisitcercose bovina e estudo da cinética de produção de anticorpos contra-Cysticercus bovis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ocorrência de leishmaniose em gatos de área endêmica para leishmaniose visceral

Despite the description of several cases of feline leishmaniasis around the world, little information is available about the importance of the cat as a reservoir of the disease. The aim of the present study was to determine the occurrence of leishmaniasis in cats from an endemic area for visceral leishmaniasis in Brazil. Two hundred cats were included in this study. Infection was evaluated through the presence of amastigotes in stained smears from fine-needle aspirates of lymph nodes, bone marrow, spleen and liver, and by antibody reactivity against Leishmania chagasi using indirect ELISA. Our results showed a prevalence of infection in 14.5% (31/200) of the feline population studied, with 4% (8/200) of positivity by parasitological diagnosis and 11.5% (23/200) by serology.

Clinical, serological, and parasitological analysis of snakes naturally infected with Cryptosporidium serpentis

Infection by Cryptosporidium serpentis is one of the most important diseases in reptiles and is characterized by chronic clinical or subclinical infection and the presence of hypertrophic gastritis, food regurgitation, progressive weight loss, mortality, and intermittent or continuous shedding of oocysts in the feces. The objectives of this study were to standardize an indirect enzyme-linked immunosorbent assay (ELISA) to detect antibodies against C. serpentis and to evaluate the clinical, parasitological, and humoral immune response in snakes naturally infected with C. serpentis. Twenty-one snakes naturally infected with C. serpentis and housed at the Butantan Institute, São Paulo, Brazil, underwent clinical and parasitological analyses for C. serpentis infection through daily records of clinical signs and a monthly survey of fecal shedding of oocysts using the Kinyoun's acid-fast staining. The serological evaluation was performed monthly by indirect ELISA using crude total antigen from oocysts of C. serpentis to detect anti-C. serpentis antibodies. Clinical symptoms consisted of food regurgitation, inappetence, and progressive weight loss. The parasitological analysis revealed intermittent fecal shedding of a variable number of oocysts in all snakes, with positivity in 85.32% (157/184) of the samples. The indirect ELISA was positive in 68.25% (86/126) of the samples. A humoral immune response was observed in most animals; however, fluctuating antibodies levels, leading to alternating positive and negative results, were observed in most snakes. © 2013 Elsevier B.V. All rights reserved.

Kinetics of epsilon antitoxin antibodies in different strategies for active immunization of lambs against enterotoxaemia

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

Detecção de anticorpos anti-leishmania chagasi em cães do município São José do Rio Preto, São Paulo

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