Figure 11. Protective efficacy of LVSΔ1423/1422 against IN challenge of mice with LVS.

Groups of BALB/c mice were injected with PBS (•), or inoculated with 6.1×10³ CFU/mouse of LVS Δ1423/1422 (▴). Six weeks PI, the mice were challenged IN with 1.4×10⁵ CFU/mouse of LVS, and the mice were monitored for 4 weeks. No mice died or were symptomatic by 10 days post-challenge. The P value for animal survival after 10 days post-challenge was <0.001.