Table 1.
Behavioral categories and definitions
| Behavioral categories | Definitions |
|---|---|
| Aggressive pecking | Pecking at head, back or neck except severe pecks (forceful pecks, sometimes with feathers being pulled out and with the recipient bird moving away) and gentle pecks (careful pecks, not resulting in feathers being pulled out and usually without a reaction from the recipient bird) |
| Threatening | The hen tries to peck the pecked hen, but the pecked hen leaves before being pecked |
| Displacing | The hen pecks the other hen’s feathers on its back with beak, or steps on back with claws, and finally takes up the position of the other hen |
| Chasing | The hen chases the other hen until the other hen runs into the corner and could not keep chasing |