RESUMO
Three indirect enzyme-linked immunosorbent assays (iELISA) based on the North American like (NA-like), European like (EU-like) and co-expressed NA- and EU-like recombinant nucleocapsid proteins (N-protein) of porcine reproductive and respiratory syndrome virus (PRRSV) were validated for the detection of the antibodies in porcine sera. A total of 422 serum samples from unvaccinated pigs were tested. The cut-off value was optimized by a two-graph receiver operating characteristics analysis at a 95% confidence level. This assay was validated with Western blot analysis and IDEXX HerdChek ELISA. Cross-reactivity results showed that iELISA was PRRSV-specific. Repeatability tests revealed that the coefficients of variation of positive sera within and between runs were less than 10%. The results indicate that iELISA is simpler to produce and perform, time-saving and suitable for large scale surveys of PRRSV infection at low cost, and is potentially useful to evaluate the efficiency of various vaccines against PRRSV.
Assuntos
Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Proteínas do Nucleocapsídeo/imunologia , Síndrome Respiratória e Reprodutiva Suína/diagnóstico , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Sequência de Aminoácidos , Animais , Reações Cruzadas , Dados de Sequência Molecular , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Valor Preditivo dos Testes , Sensibilidade e Especificidade , SuínosRESUMO
Anticoccidial effects of green tea (GT)-based diets were evaluated in chickens following oral infection with Eimeria maxima an ubiquitous intestinal parasite of poultry that impairs the growth and feed efficiency of infected birds. Five-week-old chickens were assigned to four groups (GT 0.5%, GT 2.0%, untreated/infected and non-infected control) and each group consisted of 15 chickens. Chickens were fed a standard diet supplemented with ground green tea for 2 weeks prior to infection with E. maxima (10,000 sporulated oocysts per bird). The effects of green tea on E. maxima infection were assessed by two parameters, fecal oocyst shedding and body weight gain. The green tea-fed chickens produced significantly reduced fecal oocysts (P<0.05) when compared to the E. maxima-infected group fed standard diet. The green tea-based diet, however, did not improve body weight loss caused by E. maxima infection. This study is the first to demonstrate anticoccidial effect of green tea on Eimeria parasites.
