FIG. 5.

DTH test 1 week after the booster. Salmonella antigens (10 μl, 1 mg/ml) were injected intradermally into the left ear and 10 μl of physiological saline was injected intradermally into the right ear of each mouse and the ear thickness was measured before and at 24, 48, and 72 h after injection. Values are given as arithmetic means + standard deviations (error bars) (n = 6). All immunized groups except the group that received free antigen orally induced a significantly higher increase in ear thickness compared to the control group over time (P < 0.05).