Figure 3

Survival curves of mice infected with the designated S. suis 2 strains.
A total of 40 four-week-old female BALB/c mice were randomly allocated to four groups (10 animals per group) and challenged by intraperitoneally injecting a dose of 2.5 × 107 CFU/mice. The results are representative of three independent experiments. *P < 0.05 for comparison between the mutant ΔsspA-1 and the wild-type strain 05ZYH33 or CΔsspA-1 strain; #P < 0.05 for comparison between the mutant ΔvirD4-89K and the wild-type strain or CΔsspA-1.