Antibody production in goat milk serum after virus instillation of goat mammary gland. VII. Biochemical studies on sham infection with rabies and other non-propagating agents

This report describes the development of a method for the production and isolation of neutralizing antibodies against rabies virus (ERA strain) and other agents in the goat mammary gland during active lactation. The rabies virus did not propagate in thegland, but neutralizing antibodies were produced by serial instillations of the antigen. This process was termed 'sham infection.' Antibodies first appeared in the mildabout the 20th day and the titer increased until the 28th day. The antibodies were found to be associated with the lactogammaglobulin. The milk globulins were fractionated by gel chromatography and the fraction containing the antibody was isolated. This fraction was further purified and characterized by immunodiffusion, immunoelectrophoresis, and an analytical ultracentrifugation technique. The neutralizing antibody activityafter the 29th day was associated with the milk serum IgG fraction. This acive fraction was found to have a sedimentation coefficient of 6.8 Svedberg units.