Table 2. Facial expressions during the interventions (combined) as defined by the Co-occurrence method.
| OWS | Inner brow raiser (AU101) | Lips part (AU25) | Tongue show (AD19) | Nostril Dilator (AD38) | “Ear flicker” | Blink (AU145) | Eye white increase (AD1) | Nostril lift (AUH13) | Upper lid raiser (AU5) | Half blink (AU47) | Ears forward (EAD101) | Ear rotator (EAD104) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2 | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | |||
| (p = 0.042) | (p<0.001) | (p<0.001) | (p<0.001) | (p<0.001) | (p<0.001) | (p<0.001) | (p = 0.064) | (p<0.001) | ||||
| 5 | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ||
| (p = 0.024) | (p<0.001) | (p<0.001) | (p<0.001) | (p<0.001) | (p<0.001) | (p<0.001) | (p = 1.000) | (p<0.001) | (p = 0.107) | |||
| 10 | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ||
| (p = 0.051) | (p<0.001) | (p<0.001) | (p<0.001) | (p<0.001) | (p = 0.013) | (p<0.001) | (p = 0.450) | (p<0.001) | (p = 0.185) | |||
| 15 | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | |
| (p = 0.052) | (p<0.001) | (p<0.001) | (p<0.001) | (p<0.001) | (p = 0.037) | (p<0.001) | (p = 0.576) | (p = 0.001) | (p = 0.373) | (p = 0.173) | ||
| 20 | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | |
| (p = 0.090) | (p = 0.001) | (p = 0.001) | (p<0.001) | (p<0.001) | (p = 0.053) | (p<0.001) | (p = 0.383) | (p = 0.003) | (p = 0.238) | (p = 0.217) | ||
| 30 | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| (p = 0.179) | (p = 0.018) | (p = 0.017) | (p<0.001) | (p = 0.001) | (p = 0.079) | (p<0.001) | (p = 0.450) | (p = 0.018) | (p = 0.210) | (p = 0.252) | (p = 0.641) |
Action units (AUs) and action descriptors (ADs) selected using the Co-occurrence method to represent the interventions in horses using different observation window sizes (OWS).