Table 1. Behavioural states and events selected in the focal sampling ethogram.

Phase	Event frequency (n)	Definition
Chasing	Bite threat	Trying to bite the trainer
	Bucking/shying	All four legs off the ground including kicking out with both hind legs (Waring, 2003)
	Stomping	Rapid lift of the foreleg
	Kicking with one leg	Lifting a single hind leg and rapidly extending it away from the body (Waring, 2003)
	Kicking with two legs	Lifting both hind legs and rapidly extending them away from the body (Waring, 2003)
	Head-tossing	Rapid lateral or vertical movement of the head away from the body (Waring, 2003)
	Change direction	Change in the direction: right toward left, or the reverse, in walk, trot or gallop
	Neigh/snort	Any type of neigh or snort, identified visually (i.e. not using sound)
	Sniffing	The horse sniffs the ground
	Lick and chew/oral movements	Opening of mouth with extension and retraction of tongue, lip smacking without tongue extension, lateral jaw movements involving partial opening of lips (McGreevy, 2004)
	Defecation	Evacuation of large bowel (McGreevy, 2004)
	Escape attempt	Any rapid movement directed toward the fence where the horse looks for a possible escape. This may include the horses chest touching the fence
	Head-lowering	The horse lowers head below the withers
Non chasing	Stopping face-toward or side on	Coming to a standstill with the trainer in-line with the forefeet of the horse
	Stopping during following	Coming to a standstill while following the trainer
	Stepping toward (n° of steps)	Individual steps of the forelegs toward the trainer
	Stepping back (n° of steps)	Individual steps of the forelegs backward in the opposite direction of the trainer
	Touching the trainer	Direct contact with the trainer by the nose of the horse, initiated by the horse
	Neigh/snort	Any type of neigh or snort, identified visually (i.e. not using sound)
	Defecation	Evacuation of large bowel (McGreevy, 2004)
	Sniffing	The horse sniffs the ground
	Lick and chew/oral movements	Opening of mouth with extension and retraction of tongue, lip smacking without tongue extension, lateral jaw movements involving partial opening of lips (McGreevy, 2004)
	Head-lowering	The horse lowers head below the withers
	States duration (sec)
Chasing	Walking	The horse walks
	Trot	The horse trots
	Canter/gallop	The horse gallops or canters
	Standing/stopping toward fence	The horse stops and stands toward the round pen fence
Non chasing	Standing/stopped	The horse stops and stands quietly toward their trainer
	Following	The horse follows their trainer