Fig. 4.

Preexposure immunization of SPBAANGAS-GAS-GAS, SPBAANGAS-GAS(−)-GAS(−) and UV-inactivated SPBAANGAS-GAS-GAS in Swiss–Webster mice. Groups of 10 mice were injected i.m. with 100 μL of serial 10-fold dilutions (vaccine doses: 10² to 10⁵ TCIU) of the recombinant RVs. Three weeks after immunization, mice were infected i.c. with 100 LD50 of DOG4 RV and observed for 4 weeks. (A) The percentage of survivors in the different immunization groups at 4 weeks after virus challenge. The ED₅₀ values (B) were calculated from the survivorship rates in the 3 vaccination groups as described in ref. 20.