Table 1.

Ethogram of behavioural observations.

Item	Description
Behaviour
Eating	Having head above or in the feeder and/or pecking at feed in the feeder or on the floor
Drinking	Drinking from nipple or cup beneath nipple
Locomotion	Walking (locomoting in upright position with a normal speed or quick steps) or shuffling (half standing/half sitting and moving a few steps before sitting down), without performing any other behaviour
Defecation	Excreting faeces
Standing idle	Standing on the ground without performing any other behaviour
Perching	Perching without performing any other behaviour
Resting	Sitting with hocks resting on ground without performing any other behaviour, possibly with head on the ground or under wing
Scratching	Scraping of the litter with the claws
Ground pecking	Performing pecking movements directed at the ground
Food running	Running with food in beak while pen mates follow and attempt to grab the food item
Dust bathing	Performed with fluffed feathers while lying, head rubbed on floor, wings opened, scratching at ground, distributing substrate over body
Stretching	Stretching of wing and/or leg
Preening	Grooming of own feathers with beak
Wing flapping	Bilateral up-and-down wing flapping
Agonistic	Jumping at pen mate, threatening pen mate, pecking movements directed at head of pen mate
Pecking pen mate	Pecking movements directed at the body or beak of pen mate
Interaction tube	Pecking movement directed at tube or moving tube
Other	Any behaviour not mentioned above
Posture
Standing	On floor: hocks not in contact with the litter. On perch: knees not bent
Sitting	On floor: hocks in contact with the litter. On perch: knees bent