TABLE 2.
Incidence and distribution of OTC and S/T resistance (36) and the corresponding fractions of identified tetracycline (Tet) resistance determinants and class 1 integrons (Int) among motile aeromonads isolated from four Danish rainbow trout farmsd,
| Location (n) | Area within location (No. of isolates) | % of isolates resistant to:
|
% of isolates containing Int | ||
|---|---|---|---|---|---|
| OTC | Tet | S/T | |||
| Sampling site (250) | Inlet (53) | 49a | 17 | 19a | 25a |
| Pond (92) | 71 | 33 | 49 | 47 | |
| Outlet (105) | 77 | 14 | 47 | 45 | |
| Avg | 66 | 22 | 38 | 39 | |
| Fish farm (313) | Farm 1 (69) | 65 | 17 | 61b | 67b |
| Farm 2 (98) | 75 | 30 | 42 | 43 | |
| Farm 3 (53) | 68 | 4c | 25 | 27 | |
| Farm 4 (93) | 67 | 29 | 42 | 37 | |
| Avg | 69 | 20 | 43 | 44 | |
a
Statistically significantly lower fraction than at other locations on farms (P < 0.05).
b
Statistically significantly higher proportion than at other farms (P < 0.05).
c
Statistically significantly lower fraction than at other farms (P < 0.05).
d
The comparison of different sampling sites (inlets, ponds, and outlets at the four farms) was based on Aeromonas isolates from water and sediment samples, while the comparison of fish farms also included fish isolates.