["Best fit" pathotyping of field Marek's (big liver) disease virus strains isolated in the Russian Federation in 2001-2005].

The paper presents the results of classifying 20 Russian isolates of serotype 1 Marek's disease viruses (MDV) by the adapted "best fit" method (ADOL, USA). The native SPF-chickens of the Shchelkovo line have enough susceptibility for pathotyping of MDV. The Russian isolates were classified by the pathotype in comparison with the reference strains of varying virulence; 8 of them belonged to the vv+ pathotype, 11 to the vv pathotype, and 1 to the v pathotype.