Table 3.
Experiment 3: effect of stunning method (head-only or back-of-the-head electrodes) on brain function, rhythmic breathing, peak current, and voltage in hens assessed for visually evoked potentials (VEPs).
| Stun method |
|||
|---|---|---|---|
| Head-only | Back-of-the-head | Significance | |
| Number of birds | 14 | 16 | - |
| Mean (± SE) time to return of VEPs (range), s | 20 ± 2 (9–32) | 13 ± 1 (7–26) | P < 0.01 |
| Mean (± SE) time to return of rhythmic breathing (range), s | 26 ± 1 (20–36)1 | 25 ± 1 (19–36) | P = 0.262 |
| Mean (± SE) peak current (range), mA | 453 ± 34 (280–650) | 520 ± 16 (360–620) | P = 0.086 |
| Mean (± SE) peak voltage (range), V | 138 ± 1 (131–146) | 138 ± 1 (130–142) | P = 0.754 |
| Mean (± SE) weight (range), kg | 4.0 ± 0.1 (3.2–4.7) | 4.2 ± 0.1 (3.6–4.8) | P = 0.310 |
1 No data from one animal, which died after recovery of visually evoked potentials (VEPs).