TABLE 4.
Virulence of V. anguillarum strains in juvenile Atlantic salmon
| Strain | Dose/fish (CFU) | Total % of mortality | No. of days until death (no. of fish/total fish)a |
|---|---|---|---|
| M93Sm | 3.01 × 106 | 100 | 2 (2/5), 3 (5/5) |
| 3.01 × 105 | 60 | 3 (2/5), 5 (3/5) | |
| 3.01 × 104 | 40 | 6 (1/5), 9 (2/5) | |
| S171 (vah1 mutant) | 2.9 × 106 | 100 | 2 (3/5), 3 (5/5) |
| 2.9 × 105 | 60 | 4 (1/5), 5 (3/5) | |
| 2.9 × 104 | 20 | 2 (1/5) | |
| S123 (rtxA mutant) | 1.0 × 106 | 0 | NAb |
| 1.0 × 105 | 0 | NAb | |
| 1.0 × 104 | 0 | NAb | |
| S183 (vah1 rtxA | 4.7 × 106 | 0 | NAc |
| double mutant) | 4.7 × 105 | 0 | NAc |
| 4.7 × 104 | 0 | NAb | |
| Control (NSS) | 0 | NAb |
a
NA, not applicable.
b
No fish deaths occurred during the 21-day experiment.
c
One fish in the 4.7 × 106 cells/dose group died at day 8, and two fish in the 4.7 × 105 cells/dose group died at day 12; however, no V. anguillarum cells could be isolated on LB20-Sm200 plates from the dead fish, and no clinical symptoms of vibriosis were observed.