Fig. 6From: Genome-wide analysis of a avirulent and reveal the strain induces pro-tective immunity against challenge with virulent Streptococcus suis Serotype 2Level of cytokine IFN-γ and TNF-α from different phases of plasma: Group A indicates the cytokine value from naïve piglets. Group B and C indicates cytokine values from plasma after 48 h after vaccination with strain 05HAS68 or from piglets (n = 6) that had been vaccinated twice with strain 05HAS68 and then challenged by an intravenous injection of virulent strain 05ZYH33 2 days later. Values are arithmetic means ± standard errors of the means. *, P < 0.05; **, P < 0.01Back to article page