RESUMO
Two handred and ninety five faecal samples from 45 days old calves with and without diarrhoea were processed using the ELISA, PAGE, and IFT techniques for rotavirus detection. Ninety one sample (31%) proved to be positive bu at least one of the techniques used. ELISA detected 93%, PAGE 84% and IFT 67%. Fifteen per cent of the samples were positive using ELISA and negative using PAGE, The reverse situation appeared in 5% of the samples. In 5%, 4% and 1% only of the techniques used showed the presence of the virus (ELISA, PAGE and IFT, respectively). ELISA proved to be the most sensitive technique for the detection of rotavirus in the faeces of calves. No relationship could be established between detection of rotavirus by any one of teh techniques used and age, imptomatology, geographical distribution, and electrophoretic pattern. Rotavirus was detected more frequently in diarrheic than in non-diarrheic calves
Assuntos
Lactente , Bovinos , Animais , Imunidade/efeitos da radiação , Técnicas Imunoenzimáticas , Rotavirus/patogenicidade , Vírus da Diarreia Viral Bovina/patogenicidade , Ensaio de Imunoadsorção Enzimática , ImunoeletroforeseAssuntos
Encéfalo/microbiologia , Doenças dos Bovinos/diagnóstico , Encefalite/veterinária , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 1/isolamento & purificação , Animais , Bovinos , Surtos de Doenças/veterinária , Encefalite/diagnóstico , Infecções por Herpesviridae/diagnóstico , Técnicas Imunoenzimáticas , Hibridização de Ácido NucleicoRESUMO
Genomic variations in electropherotypes of bovine rotavirus were analyzed in dairy farms. A unique electropherotype was detected in each farm which persisted at least for a year. In one farm a dual infection and a second electropherotype were detected.
Assuntos
Doenças dos Bovinos/microbiologia , Diarreia/veterinária , RNA Viral/análise , Infecções por Rotavirus/veterinária , Rotavirus/classificação , Animais , Bovinos , Diarreia/microbiologia , Eletroforese em Gel de Poliacrilamida , Fezes/microbiologia , Rotavirus/genética , Rotavirus/isolamento & purificação , Infecções por Rotavirus/microbiologiaRESUMO
When cells are grown for two rounds of DNA replication in the presence of the thymidine analogue 5-bromodeoxyuridine, chromosomes containing one chromatid with unifilarly substituted DNA and one with bifilarly substituted DNA are found. These can be distinguished by harlequin staining techniques that stain one chromatid dark and one light. When the degree of substitution is 60% or greater, 3 times as many X-ray-induced chromatid breaks are produced as in unsubstituted chromatids. This represents maximal sensitization. The unifilarly substituted (dark) chromatid is as sensitive as its bifilarly substituted (light) sister chromatid. If cells are grown in low concentrations of 5-bromo-deoxyuridine (BrdUrd), then the amount of substitution is less and the bifilarly substituted chromatid is more sensitive than the unifilarly substituted one. When large numbers of cells are grown in very low concentrations of BrdUrd, the analogue is almost completely depleted during the first round of replication leading to harlequin chromosomes containing one unsubstituted (dark) and one unifilarly substituted (light) chromatid. Under these conditions a maximal sensitization between light-staining and dark-staining chromatids can occur. This can be confused with the differential sensitivity between unifilarly and bifilarly substituted chromatids. The apparent discrepant results obtained by different investigators are most likely caused by the use of very low levels of BrdUrd in some of the experiments.
