Table 2.
Ethogram for behavioural observation of the 5-min test sessions. Behaviours within the same category are mutually exclusive unless stated otherwise. Behaviours were coded as state events unless stated otherwise. Definitions adapted from other studies are cited.
| Category | Behaviour | Definition |
|---|---|---|
| Activity | Contact by pig | Pig makes active contact with human. Includes sniffing, nosing, oral manipulation, rubbing, pawing |
| Body contact26,a | Pig makes body contact with human. Includes climbing on human, standing with body against human, and lying or sitting on human | |
| Contact by humanb | Pig receives active contact (stroking, scratching, rubbing) by the human | |
| Following | Pig takes more than two steps in the same direction as the moving human | |
| Moving towards | Pig takes more than two steps in a direction that decreases the distance between pig and human | |
| Moving away | Pig takes more than two steps in a direction that increases the distance between pig and human | |
| Exploring the penc | Pig’s snout touches pen floor or wall for more than 1 s | |
| Lying downd | Pig’s thorax touches the ground | |
| Immobile | Pig is either sitting or standing for more than 2 s and less than 30 s, shows no specific movement | |
| Inactive (Sara Hintze, unpublished) | Pig is either standing or lying, shows no specific movement for more than 30 s. Pig remains inactive if it engages in exploration maximum twice or for less than 5s, takes less than five steps away, stretches or changes posture | |
| Escape behaviourc | Pig nudges/pushes against pen door using snout or front legs; climbs door, wall or into back corner | |
| Escape attempte | Pig jumps against the door or wall | |
| Eliminatione | Pig excretes faeces or urine | |
| Not visible | Pig’s behaviour cannot be determined due to snout being obstructed from view | |
| Tail posture and movement66 | Hanging tail | Tail is pointing downward |
| Curled tail | Tail coiled up in a curl on top of the body | |
| Tucked tail | Tail is kept vertically down and close to the body whereby the tip of the tail is held between the legs | |
| Wagging | Tail swinging in any direction, but mostly from side to side | |
| Not visible | Pig’s tail posture or movement cannot be determined due to tail being obstructed from view | |
| Vocalisations26 | Low-pitched vocalisation | Grunts |
| High-pitched vocalisation | Grunt-squeals, squeals, and screams |
a‘Body contact’ did not exclude ‘Contact by pig’, ‘Contact by human’, ‘Immobile’, ‘Inactive’, ‘Other’, and ‘Not visible’.
b‘Contact by human’ did not exclude any behaviours.
cAn interruption of > 3 s was considered a new bout.
d‘Lying down’ did not exclude ‘Contact by pig’, ‘Contact by human’, ‘Exploring’, ‘Inactive’, ‘Other’, and ‘Not visible’.
eScored as point event due to short duration.