BIOKINEMATIC EFFECTS OF COLLECTION ON THE TROTTING GAITS IN THE ELITEDRESSAGE HORSE

Trot in hand, working trot, collected trot, passage and piaffe of 6 Gr and Prix dressage horses were recorded by high speed film (250 frames/ s), Angular patterns and hoof trajectories of the left fore- and hindl imbs were analysed and presented as mean and standard deviation (s.d.) curves, Speed and stride length decreased and fore- and hind stance p hase durations increased with collection resulting in no suspension In piaffe. The diagonal advanced placement was positive in all gaits exc ept for piaffe, Most of the changes in forelimb angular patterns were effects of reduction in forelimb pendulation. The horses did not step under themselves more in collected trot, passage and piaffe than in tr ot in hand. The stifle and hock joints were more flexed at the start o f the stance phase in piaffe and passage than in the other gaits. Flex ion of the hock joint at the middle of the stance phase was largest in passage and piaffe, In spite of the limited number of horses the pres ent study confirmed earlier observations of conformation and gaits in dressage horses, Hindlimb pendulation, femur and pelvis inclinations a nd elbow, carpal, stifle and hock joint angles seem to be the most sig nificant angular measurements for dressage performance.