Haralambiev H
Arch Exp Veterinarmed. 1975;29(5):777-80.
Cross-neutralization tests of the C24V strain and the "Kotschmar" strain provided evidence that the two strains are serological variants. Independenthy of quantitative serological differences, these strains had a better immunizing action in calves against a virulent strain of MD/VD virus. This virulent strain evidently formed a third serological variant, because when calves were infected with it, there was a decrease in the serological differences between antibodies. A practical conclusion is that diagnostic serological testing using only one strain is unlikely to detect all the infected animals, particularly those with low titres of antibody. In the presence of complement the neutralizing capacity of immune serum increased and, in the case of low antibody titres, serological differences between strains decreased. Therefore the complement-dependent neutralization test with at least two strains of virus is recommended for use in diagnostics.
对C24V毒株和“科奇马尔”毒株进行的交叉中和试验证明，这两种毒株是血清学变异株。尽管存在定量血清学差异，但这些毒株对犊牛抵抗MD/VD病毒强毒株具有更好的免疫作用。这种强毒株显然形成了第三种血清学变异株，因为当犊牛感染该强毒株时，抗体之间的血清学差异减小。一个实际结论是，仅使用一种毒株进行诊断性血清学检测不太可能检测出所有感染动物，尤其是那些抗体滴度较低的动物。在有补体存在的情况下，免疫血清的中和能力增强，而且在抗体滴度较低的情况下，毒株之间的血清学差异减小。因此，建议在诊断中使用至少两种病毒毒株进行补体依赖中和试验。
