Figure 2.

Expression of multiple regulator genes in field isolates of S. Choleraesuis. The expression of multiple regulator genes in resistant strains and low enrofloxacin-accumulating nalidixic acid-susceptible strains was compared to the average expression of the corresponding genes in high enrofloxacin-accumulating nalidixic acid-susceptible strains (n = 6). Horizontal line indicates the average gene expression in the six susceptible strains, which expressions were set to be 1.0. *Indicates that mRNA expression is significantly higher in a strain compared to mRNA expression in the six susceptible strains (P < 0.05).