Figure 5. Development of FQ^R Campylobacter mutants in chickens initially infected with FQ-susceptible Campylobacter, but treated with enrofloxacin.

(A) The level of total Campylobacter in each chicken inoculated with the wild-type 11168 (open circle) or the mfd mutant strain (JH01; solid circle). The treatment with enrofloxacin started on day 0 and lasted for five consecutive days (indicated by a bracket on top of the panel). (B) The level of FQ^R Campylobacter in each chicken inoculated with the wild-type (open circle) or the mfd mutant (solid circle). In both panels, each symbol represents the number of Campylobacter in a single bird. Each group includes eleven chickens and the mean of each group at a given time is indicated by a horizontal bar. A chicken is considered negative if the level of colonization was below the detection limit (10² CFU/ g of feces).