Summary Trot in hand, working trot, collected trot, passage and piaffe of 6 Grand Prix dressage horses were recorded by high speed film (250 frames/s). Angular patterns and hoof trajectories of the left fore‐ and hindlimbs were analysed and presented as mean and standard deviation (s.d.) curves. Speed and stride length decreased and fore‐ and hind stance phase durations increased with collection resulting in no suspension in piaffe. The diagonal advanced placement was positive in all gaits except 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 trot in hand. The stifle and hock joints were more flexed at the start of the stance phase in piaffe and passage than in the other gaits. Flexion 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 present study confirmed earlier observations of conformation and gaits in dressage horses. Hindlimb pendulation, femur and pelvis inclinations and elbow, carpal, stifle and hock joint angles seem to be the most significant angular measurements for dressage performance.

Summary The movements of the individual limbs of 30 clinically sound Standardbred trotters were studied using high‐speed cinematography. At a speed of 12 metres per second (m/sec; 1:23.6 min/km) the mean stride length was 545 cm and the mean duration of the stride was 455 milliseconds (msecs). The stance phase in the forelimbs was 110 msecs and 117 msecs in the hindlimbs. This difference was due to a longer restraint period in the hindlimbs and resulted in slightly shorter swing phases for the hindlimbs. The variations in any particular horse for stride length and for the duration of stride, stance, swing and propulsion were very small (variation coefficient: approximately 2 per cent). For the restraint stage, however, the variation coefficient was around 5 per cent. The variations noted between different horses were generally 2 to 3 times greater than those recorded for the same horse. There was a close correlation between stride and swing phase duration, suggesting that the swing phase was the main contributor to the stride‐time variations of different horses trotting at the same speed. The restraint and propulsion stages did not seem to play an important role in this respect for this group of animals. Résumé Les mouvements individuels des membres de 30 trotteurs Standardbred cliniquement sains ont étéétudiés à l'aide du cinématographe à grande vitesse. A la vitesse de 12 mètres seconde (soit 1m23 seconde 6/10 du kilomètre), la battue moyenne était de 545 cm et la durée moyenne de chaque battue était de 455 millisecondes. La phase d'appui des antérieurs durait 110 millisecondes, celle des postérieurs durait 117 millisecondes. Il en résultait une phase en suspension légérement plus brève pour les postérieurs. Les variations pour chaque cheval en particulier, de la longueur et de la durée de la battue des phases à l'appui, en suspension de soutien, de propulsion, furent très faibles (variations d'environ 2%). Pour la phase de retenue, le coéfficient de variation était d'environ 5%. Les variations observées entre les différents chevaux étaient en général deux ou trois fois plus importants que celles constatées chez le même cheval. On remarque une étroite corrélation entre la durée de la battue et celle de la phase suspension; cette corrélation parait indiquer que la phase en suspension est le principal facteur des variations des temps de battue de différents chevaux trottant à la même vitesse. Les temps de retenue et de propulsion n'ont pas semblé jouer un rôle aussi important dans ces groupes d'animaux. Zusammenfassung Die Bewegung der einzelnen Gliedmassen von 30 klinisch gesunden Trabern wurde anhand von Hochgeschwindigkeits‐filmen untersucht. Bei einer Geschwindigkeit von 12 m/sec (1'23.6“/km) betrug die mittlere Schrittlänge 545 cm und die mittlere Schrittdauer 455 m/sec. Die Stützbeinphase betrug für die Vorderbeine 110 m/sec und für die Hinterbeine 117 m/sec. Der Unterschied ist die Folge eines verzögerten Abhebens der Hinterbeine, was eine etwas kürzere Hangbeinphase nach sich zeiht. Die Variationen beim e...

Summary The trotting gait of 4 approved Swedish Warmblood stallions with a mean gait score ≥8.67 (maximum score = 10) at official performance tests and 4 horses with poor gaits (mean gait score ≤6.5) was recorded by high speed film (250 frames/s). Angular patterns and hoof trajectories of the left fore and hind limbs were analysed and presented as mean and standard deviation curves. The good horses had longer stride duration (p<0.001) and larger positive diagonal advanced placement (p<0.01). The swing phase retraction in the forelimbs was longer in the good horses. The most important differences in the forelimb angular patterns were found in the elbow and carpal joint angles. They were considerably more flexed in the good horses at the beginning of the swing phase retraction. Larger decrease of the pelvis inclination, increase of the femur inclination and larger flexion of the hock and hind fetlock joints during the stance phase were correlated with high trot scores. This indicates that storage of elastic strain energy during the stance phase may be important for the elasticity, energy and propulsion in trot.

Summary Ten trotting Standardbred colts were recorded by high‐speed cinematography at the ages of eight, 12 and 18 months. The horses were trotting on a treadmill operating at 4.0 m/secs. Five horses were subjected to a programme of intensified training from eight months of age, whereas the others were not trained and acted as controls. The films were analysed on a semi‐automatic film‐reading equipment and a number of variables used to demonstrate the gait symmetry were calculated and scaled by computer. Certain differences between left and right diagonal and contralateral pair of limbs, respectively, were noted, suggesting that laterality in horses may be inherited. The most pronounced systematic differences were found in 18‐month old horses in the trained group. The results show the importance of careful gait examination and comprehensive coordination training at an early age.

Summary A treadmill for equine locomotion analysis is described and its potential considered for locomotive research and clinical investigation. The treadmill comprised an endless belt driven by a hydraulic motor at various speeds up to 14 m/sec and the direction of belt movement was reversible. The carrying side of the belt ran over a steel‐concrete table which acted as a flat support. The belt itself consisted of a steel base on to which was glued a rubber belt and the surface was covered with a layer of coir matting which permitted some forward sliding of the landing hoofs simulating the conditions on an ordinary track. The treadway could be inclined up to 10° in the longitudinal and 7.5° in the transverse direction. To minimise the risk of injuries a special emergency stop system was installed. Horses adapted well to exercising on the treadmill, even without any previous experience. A good correlation was found between the gait repetivity on the racetrack and that displayed on the treadmill. One horse recorded both on the racetrack and on the treadmill showed significantly shorter strides on the treadmill but this did not invalidate the treadmill as a useful research tool in the study of equine locomotion. Résumé On dócrit un tapis roulant pour l'analyse de la locomotion équine. Les possibilités de cet appareil sont envisagées tant pour l'étude de la locomotion que pour la recherche clinique. L'appareil comporte un tapis sans fin entraîné par un moteur hydraulique à des vitesses variables jusqu'à 14 mètres/seconde; la direction du mouvement est réversible. La face porteuse du tapis se déplace audessus d'une table d'acier et béton agissant comme support. Le tapis lui‐même consiste en un squelette d'acier recourvert d'une couche de caoutchouc; la surface est recouverte d'un revêtement en fibres végétales qui permet un léger glissement en avant des sabots venant au contact dans des conditions comparables à celles d'une piste ordinaire. Le tapis peut être incliné de 10° dans le sens longitudinal et de 7°5 tranversalement. Pour diminuer le risque d'accident un système permet l'arrêt d'urgence. Les chevaux se sont bien adaptés à l'exercice dans cet appareil même s'ils n'en avaient pas encore l'expérience. Une bonne corrélation fut observée entre la répétitivité des allures sur la piste et des allures sur le tapis. Un cheval étudié sur la piste et sur le tapis montra sur ce dernier des pas raccourcis. Cet appareil n'en n'est pas moins un très utile moyen d'étude de la locomotion équine. Zusammenfassung Eine Tretmühle zur Analyse der Fortbewegung des Pferdes wird beschrieben und ihr Potential für Forschung und klinische Untersuchungen besprochen. Die Tretmühle besteht aus einem Endlosband, das von einem hydraulischen Motor in verschiedenen Geschwindigkeiten bis zu 14 Meter pro Sekunde angetrieben wird. Die Richtung des Bandlaufes kann umgekehrt werden. Die Tragfläche des Bands läuft über einen Stahlbetontisch, der als flache Unterlage dient. Das Band selber besteht aus einer Stahlgrundlage, auf die eine Gummischicht ...