TABLE 3.

Ethogram of coded behaviors.

Category	Variable	Description
Latency choice	Latency to consume LVR/HVR	Time from start of trial until horse either closed his/her lips around the LVR or until the delay time has passed
Attention	Look away	Head turned away in >45° angle from experimenter
Distance	Large distance	Horses’ mouth is more than 0.5 m away from the hand holding the LVR
Other behaviors	Empty chewa	Horse chews without having food in his/her mouth
	Oral manipulation	Licking, nibbling or biting into barrier/box/door or own body parts
	Head movement	Any repeated movements with the head (i.e., horizontal and vertical movements or rotational movements)
	Flehmen	Lifting the upper lip, usually associated with a forward stretched neck
	Pawing	Repeatedly lifting one leg and scratching with the hoof on the ground
Reward-directed behaviors	Sniffing LVR	Sniffing on LVR without taking it into the mouth
	Pushing LVR	Pushing hand holding LVR away with mouth or head

^aOnly coded after 10 s of a trial had elapsed to avoid coding instances of horses still chewing the previous reward.