Speed of gaits in Icelandic horses and relationships to sex, age, conformation measurements and subjective judges' scores

The aim was to measure the mean and maximum speed and the range of speed in all gaits of Icelandic horses shown at a breed evaluation field test (BEFT). In addition, the effect of speed on scores for the gaits and whether speed was affected by age, sex and conformation measurements were investigated. The study was carried out in Iceland on 266 horses (180 mares and 86 stallions). Horse speed and distance ridden were recorded by global positioning system during the riding assessment in BEFT. Conformation measurements and scores for each gait were obtained from the official studbook Worldfengur. The range of speed in walk, slow tolt, tolt, trot, pace, canter and gallop was, respectively, 1.5-2.2, 3.2-5.5, 16-10.6, 4.5-8.6, 7.1-11.9, 5.8-9.8 and 7.9-13.5 m/s (n=149-248). Scores for all gaits were affected by speed of the gait, with speed explaining most variance in scores for pace (53%) and least in scores for slow tolt and walk (2 and 3%, respectively). Stallions were faster than mares in tolt, trot, pace and canter (P= 7 years and 6-year-olds were faster in pace and canter than 4-year-olds (P<0.05). Horse conformation measurements most affected speed in pace and walk, which were elevated with increased height at withers, height at croup, body length and length of front legs (P<0.05). In conclusion, objective measurements of speed in the gaits of Icelandic horses shown in a BEET were documented for the first time. The information can be used to formulate requirements for gaits in BEFT and in competition manuals. Objective measurements of speed should be used in future assessments of gaits in Icelandic horses in BEFT, and thus improve standardisation and genetic evaluation of breeding horses.