In each experiment, fish in challenge tanks received doses of
F. columnare cells from the same incubated stock solution. In Experiment
1, the bacterial suspension equivalent was 1.2 × 108 colony
forming units per mL (CFUs/mL) and for Experiment 2, the bacterial
suspension equivalent was 6.0 × 107. In brief, F. columnare isolate LV-
359-01 (a genomovar II isolate; Beck et al., 2012) was streaked on
Ordals' Medium (Anacker and Ordal, 1959). After 48 h, the isolate was
dislodged from the agar using a sterile cotton swab and inoculated
into 5 mL of F. columnare Growth Medium (FCGM; Farmer, 2004).