Oreochromis niloticus sound parameters (means ± s.d.) under stimulation, without (Stim) and with pierced swimbladder (SW KO) and results of the Mann–Whitney U-test
| Variables . | N fishes . | N pulses Stim . | N pulses SW KO . | Mean ± s.d. Stim . | Mean ± s.d. SW KO . | M–W P (<0.05) . |
|---|---|---|---|---|---|---|
| Duration (ms) | 4 | 80 | 68 | 133.5±15,3 | 133.1±19.4 | NS |
| Frequency (Hz) | 4 | 80 | 68 | 34.6±3.1 | 32.1±3.3 | NS |
| dB rel. | 4 | 80 | 68 | 30.3±2.1 | 38.6±4.2 | *** |
| Variables . | N fishes . | N pulses Stim . | N pulses SW KO . | Mean ± s.d. Stim . | Mean ± s.d. SW KO . | M–W P (<0.05) . |
|---|---|---|---|---|---|---|
| Duration (ms) | 4 | 80 | 68 | 133.5±15,3 | 133.1±19.4 | NS |
| Frequency (Hz) | 4 | 80 | 68 | 34.6±3.1 | 32.1±3.3 | NS |
| dB rel. | 4 | 80 | 68 | 30.3±2.1 | 38.6±4.2 | *** |
P>0.05=NS and P<0.001=***