Differentiation of cytopathic and noncytopathic isolates of bovine viral diarrhea virus by virus neutralization.

Soluble antigens of cytopathic and noncytopathic isolates of bovine viral diarrhea virus were resolved by high-performance liquid gel-permeation chromatography into 4 major and 3 minor peaks. The 2 peaks with the larger molecular weights (240,000 and 140,000 daltons) were immunogenic when inoculated into rabbits. Virus neutralizing antibodies were specific for the homologous virus. The soluble antigens were determined to be greater than 100,000 daltons by filtration.