Absence of population asymmetry in the American Quarter Horse (Equus ferus caballus) performing skilled left and right manoeuvres in reining competition

Abstract

Use of the right hand by humans for speech-related hand gestures, writing and throwing exemplifies motoric asymmetry. There are reports of asymmetry in many other animal species, including reports of left preference in emotional responsivity, spontaneous behaviour and the trained performance of the horse, Equus ferus caballus. The present study used the novel approach of using judges' scores to examine asymmetry in an equestrian event. The study analysed the scores of five judges evaluating the reining performance of 482, three-year-old American Quarter Horses competing in a major competition. Reining requires that the horses perform the manoeuvres of spin, circle and stop directed to either the left or right and symmetrical performance is featured in the judging criteria. The scores were sensitive to performance level, sex and manoeuvre, but there was no evidence of a population asymmetry in the left vs. right direction of the manoeuvres. The results are discussed in relation to need of using a large number of subjects in measuring asymmetry, the expression of individual vs. population asymmetry as a function of morphological and behavioural measures, and the influence of behavioural training on asymmetry.

The laterality of the gallop gait in Thoroughbred racehorses

“…The current results align with Wishaw [ 44 ], who found no evidence of population laterality and only a few horses that were individually lateralised. Duel and Lawrence [ 45 ] noted that ridden horses were more likely to initiate gallop with the L leading leg, but their study (n = 4) was too small to assess for population asymmetry.…”

From Science to Practice: A Review of Laterality Research on Ungulate Livestock

“…In this section, the findings will be discussed according to the significance of these findings for different scientific fields and practical applications. Stepping up: [59] Unloading from truck: [59] Obstacle avoidance: [64] Rolling: [64] Stretching: [55] Turning during flight: [68] Suckling: [69] Competition maneuvers: [70] Locomotion: [53,61,63,64] Standing: [56] Obstacle avoidance: [64] Rolling: [64] Cattle Lying: [71], [ Foot movements during transport: [86] Side preference in maze: [87] Obstacle avoidance:…”

A comparison of different established and novel methods to determine horses' laterality and their relation to rein tension

“…Motor laterality has been determined by observing the preferred advanced forelimb during foraging either on pastures ( 32 – 35 ) or with standardized preference tests ( 36 , 37 ), by documenting the preferred limb for the initiation of movement ( 38 ) or truck loading ( 39 ), the preferred lead during flat racing ( 40 ), as well as the preferred turning side to avoid obstacles ( 38 ), the preferred side to roll on ( 38 ) and the lateral derailment of the hindquarters while standing ( 41 ) or trotting on a circle ( 42 ) in foals and young horses. Laterality, as assessed by the riders ( 43 – 45 ) or by experimenters based on judge's scores during competitions ( 46 , 47 ), has been evaluated. However, other test methods have rarely been investigated for agreement with laterality during riding or among each other, and agreement between studies was limited ( 36 , 38 ).…”