FIG. 1.

MTZ-induced toxicity/lethality. Wild-type (nontransgenic) larvae were treated at 4 dpf with the indicated concentrations of MTZ for 4, 24, or 48 h (shaded boxes, lower left). The number of viable fish was counted each day through 8 dpf; the percent of viable fish for each day is shown. Data are averages from two to three trials; error bars are SEM. Data were analyzed by chi-square analysis: no significant differences (χ²>0.05) were evident between conditions after 4 h treatments (left panel); ^# marks the first data point in each data series that is significantly different (χ²≤0.05) from corresponding untreated control data points (0.1% DMSO), with all subsequent data points in each series also being significantly different; all other data points are not significantly different from untreated controls. DMSO, dimethyl sulfoxide; dpf, days postfertilization; MTZ, metronidazole.