Fig. (3) A. Survival of Dutch-belted rabbits treated with various doses of ciprofloxacin for six days beginning 24 h after nasal instillation challenge with 100 LD₅₀B. anthracis Ames spores. The horizontal bar indicates the period of treatment (6 days). The highest dose was significant starting at day 3 and continuing through the end of the study. Significance for the 5 mg/kg/day group only lasted for days 2.5 and 3, while the two lowest doses were not significant. Significance from the control was determined by the Fisher Exact Test (p<0.05). B. Survival of Dutch-belted rabbits treated with various doses of levofloxacin. For all groups, significance (p<0.05) started on day 2.5, and while the two highest doses were significant through the end of the study, the 3.57 mg/kg group was only significant through day 4, and 1.78 mg/kg/day, only through day 3.