Figure 2: The antibody response of a) S. suis 2 b) rSao-specific IgG in the serum of piglets from sows with or without (n=5 each) prepartum immunization with inactivated S. suis 2+rSao. Data are represented as Mean ± SEM of peak absorbance values as determined by indirect ELISA performed on diluted (1:500) serum samples. Treatments with different superscript letters at each time point are significantly (p<0.05) different. S/P ratio = (sample – Nˉx) /(PCˉx – NCˉx)