| 摘要 |
FIELD: medicine. ^ SUBSTANCE: group of inventions involves a method for virulence prediction of PRRS virus isolate of unknown virulence, as well as a composition which contains the attenuated forms of PRRS virus to be predicted for virulence. The method for virulence prediction of consists in the fact that PRRS virus isolate of unknown virulence is introduced in a certain amount to a pig, and PRRS virus is enabled to replicate over the period of time within 3 to 15 days. During this period, PRRS virus isolate growth rate and/or viremia level are evaluated and compared with the reference growth rate and-or and/or viremia level of PRRS virus isolate of known virulence. And PRRS virus isolate is supposed to exhibit high virulence if growth rate and/or viremia level are similar to such values specific to high virulence isolate, and PRRS virus isolate is expected to have low virulence if growth rate and/or viremia level are similar to such values specific to low virulence isolate. ^ EFFECT: method allows to predict virulence of new and nondescribed PRRS virus isolates to be thereafter applied in immunological compositions. ^ 12 cl, 9 dwg, 6 tbl, 2 ex |
