FIG 6.

The sensitivity of P. multocida to chicken serum. The killed percentage of the wild-type strain, mutant strain, and complemented strain in the unheated and heated sera is given. When CFU/mL at 3 h < CFU/mL at 0 h, killed percentage = |(CFU/mL at 3 h) − (CFU/mL at 0 h)|/(CFU/mL at 0 h) × 100%. When CFU/mL at 3 h ≥ CFU/mL at 0 h, killed percentage = (CFU/mL at 0 h)/|(CFU/mL at 3 h) − (CFU/mL at 0 h)| × 100%. Data are expressed as the mean ± standard deviation from three independent experiments. ***, P < 0.001. The experiments were performed at least three times.