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Electrocardiograms of chickens infected with viscerotropic velogenic Newcastle disease virus (NDV) or virulent avian influenza virus (AIV) were characterized and compared. The ECG were monitored by radiotelemetry and were recorded twice daily before virus infection and during the course of the infection. Thirteen lead II intervals, segments, and amplitudes were measured and analyzed. The ECG of NDV-infected chickens were characterized by lengthened (P less than or equal to 0.05) ST segments and increased (P less than or equal to 0.05) P amplitudes. The ECG of AIV-infected chickens were characterized by lengthened (P less than or equal to 0.05) RS intervals, ST segments, TP intervals, and PR segments and by increased (P less than or equal to 0.05) P amplitudes. The TP intervals and PR segments of ECG of AIV-infected chickens were significantly (P less than or equal to 0.05) longer than those of NDV-infected chickens. The pronounced conduction delays indicated in the ECG of AIV-infected chickens may have diagnostic importance. 相似文献
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The detection and identification of Streptococcus suis type 2 in 8.1% of 347 pig herds of southwestern Ontario revealed that the infection is widespread in this area. A herd suspected to be infected showed a carrier rate of 9.7% among the 62 animals sampled. These subclinical carriers represent a potential source of infection for slaughterhouse workers. From studies of contamination of hands and knives, it was concluded that eviscerators involved in removing the larynx and lungs from the carcasses have a significantly higher (p less than or equal to 0.05) risk of exposure to Streptococcus suis than other abattoir workers. 相似文献
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The application of the soluble antigen fluorescent antibody test for the diagnosis of avian influenza. 
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下载免费PDF全文 The application of the soluble antigen fluorescent test as a tool for serological investigation of influenza type A infection in wild birds was studied. The soluble antigen fluorescent antibody test is basically an indirect fluorescent antibody test except that an artificial matrix of cellulose acetate discs is used as a substrate for antigen and the test results are scanned and recorded by a fluorometer. THe influenza type A soluble antigen fluorescent antibody was obtained from concentrated and detergent disrupted virus particles, absorbed onto cellulose acetate discs. Anti-influenza sera were prepared in pheasants and ducks to A/turkey/Ontario/6118/67 and in pigeons to A/turkey/Ontario/6213/68. The antigen-antibody complex was detected by specific staining with monovalent or polyvalent fluorescein isothiocyanate conjugated rabbit anti-avian immunoglobulins. The soluble antigen fluorescent antibody test is a sensitive technique for the detection of specific influenza A antibodies in several avian species, and could be adapted for use in large scale surveys. 相似文献
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C. Mitchell 《The Journal of small animal practice》1987,28(12):1103-1104
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