FIG. 4.

IgA response to serotype Typhimurium TetC in animals 21 days following inoculation with serotype Typhimurium vaccine strains. IgA specific for TetC (A) or IgG specific for TetC (B) was quantified from serum derived from peripheral blood by ELISA. The titer for each animal (circle) and the mean titer for each group (horizontal bar) are indicated. The mutations of the serotype Typhimurium strains tested are indicated below the graph. All groups are aroA. − and + indicate the absence or presence of pTetCnirB.