FIG. 2.

Mean antibody response of the adult horse group, the pneumonic foal group, and the clinically normal foal group to each of the six Vap proteins (VapC to VapH) expressed as a ratio to the VapA titer. Titers of antibody to each protein were determined by ELISA. Significant differences (P ≤ 0.05 by Student's t test) between the adult and pneumonic groups are indicated by a, those between the pneumonic and clinically normal foal groups are indicated by b, and those between the adult and clinically normal group are indicated by c.