The antibody responsiveness to and the specific vaccination effect of rabies virus infection were investigated in high- and low-responder lines of mice produced by two-way selective breedings for quantitative production of antibodies to flagellar (H/f and L/f lines) or somatic (H/s and L/s lines) antigens of salmonellae. After specific immunization, both high lines were more resistant to rabies virus infection than were the low lines, and the protector effect was related to the level of antibody produced, as demonstrated by neutralizing serum activity. The present findings confirm the nonspecific genetic modification of the general antibody responsiveness induced in high- and low-responder lines selected for quantitative antibody production.