ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04862.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryThe forelimb kinematics of 24 Dutch Warmbloods were recorded at the trot on a treadmill (4m/s) at the age of 4, 10, 18 and 26 months using a modified CODA‐3 apparatus to study the development of the equine locomotor apparatus. Stride and stance duration increased with age, but swing duration and pro‐/retraction angle were consistent. The timing of maximal fetlock extension during the stance phase and carpal flexion during the swing phase did not change significantly as horses grew older. Moreover, individual angle‐time and angle‐angle diagrams recorded at 4 and 26 months showed a remarkable resemblance, both visually and numerically. From these data it can be concluded that horses seem to have an inherent intralimb coordination

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04863.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryAn accelerometric device was developed for evaluating the gait of young horses in field situations. Some measurements and data analysis were made to show its potential applications in gait analysis. The transducers consisted of two accelerometers measuring acceleration along the longitudinal and dorso‐ventral axes of the horses. They were put into a leather pocket applied over the sternum by means of an elastic girth fastened onto the horse. This accelerometric belt was connected to a light weight radio telemetric system. The signals were transmitted to a receiver connected to a portable microcomputer. An alternative method to use this device was to connect it directly to an analog‐digital converter of the microcomputer. The maximum data acquisition rate was 50 Hz for each accelerometer using the telemetric system and 3500 Hz using direct connection. The accelerometric device could be used either on a treadmill or in field situations. Longitudinal and dorsoventral acceleration of the sternum provided some information about basic temporal stride kinematics and kinetics of a running horse. Two tests illustrated the usefulness of the accelerometric belt to investigate the velocity‐dependent changes in stride frequency and longitudinal acceleration, and the gait asymmetry of a lame horse. Three signal analysis procedures were used for data analysis, respectively: Fourier analysis, peak‐finding and autocorrelation functions. It was concluded that the accelerometric belt allows an objective study of some basic characteristics of the horse locomotion in field situations. It could be useful to test young horses provided that standardised protocols are developed to measure and analyse the accelerati

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04864.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryHabituation to treadmill locomotion was investigated in ten Dutch Warmblood horses during a one‐week training programme. Kinematics of the horses were recorded using a CODA‐3 system and unidirectional accelerometers attached to all hooves. Horses were exercised for five days, twice a day at the walk and trot for five minutes at both gaits. Temporal and spatial stride variables and vertical trunk movement were analysed.The results indicate differences in habituation between different variables and gaits. At the walk, changes in stride duration and limb movement angle were found up to the last measurement. At the trot, all variables including constancy of stride approached constant values by the third session. At the beginning of each training session rapid adaptation occurred, disregarding the first minute of a session for locomotion studies. In conclusion, locomotion analysis at the trot requires training for a minimum of two sessions. For measurements at the walk, longer periods are recommen

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04865.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryHigh speed cinematography (150 Hz) was used to determine the linear and temporal characteristics of the collected, working, medium and extended canters in 6 highly trained dressage horses. Analysis of variance and Waller‐Duncan Bayes K‐ratio t‐tests were applied to determine which of the measured variables changed significantly among the 4 gait types. The mean speed increased progressively from the collected to working to medium to extended canters (p<0.01). Changes in speed were due to adjustments in stride length while stride duration remained constant. An increase in stride length was the result of increases in the distances between successive limb placements except the diagonal distance between the leading hind and trailing front limbs which did not change. The greatest increase was between the leading front limb and the subsequent placement of the trailing hind limb. Although the same stride duration was maintained in the 4 canter types, there were significant changes in the temporal relationships between the footfalls. The step duration between the 2 front limbs was significantly reduced from the collected to working to medium to extended canters (p<0.01). The step duration between the 2 hind limbs was significantly shorter in the extended than the collected canter (p<0.01). The stride duration was maintained by increasing the duration between the leading front and trailing hind

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04866.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummarySix Thoroughbred fillies undertook a high intensity treadmill exercise programme over an 8 week period. Kinematic parameters of the left front limb were measured using the MacReflex system as the horses were cantered on a left lead. Measurements were made as the horses performed a standardised stepwise exercise test on the treadmill (speeds 7‐11m/s, 0% slope.) The aim was to study objectively the effects of training on the equine locomotor apparatus and to test the hypothesis that horses would display mechanical adaptation to aspects of their gait, as a result of treadmill training. The variables measured were stride length; stride frequency; stance time, as a percentage of stride time; relative movements of limb joints in the X (horizontal) and Y (vertical) directions; angles about the carpus and fetlock joints; and total ranges of motion of the carpus and fetlock joint. Statistical significance was chosen at the level p<0.05. Training induced significant changes to several aspects of the stride cycle. Percentage stance times were reduced across all speeds and significant changes were observed in the movements of the limb joints resulting in increased vertical hoof lift. Significant increases were also seen in the carpal and fetlock joint ranges of motion and also in carpal joint angles. The results suggest that the training regime employed produced significant alteration in stride kinematics at the cante

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04867.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryStacked rectangular rosette strain gauges were used to measure surface bone strain on the dorsomedial cortex of the third metacarpal bones in 6 yearling (16 to 19 months old) Thoroughbred horses during exercise on a treadmill. The peak principal compressive and tensile strains, angle of the peak strains and strain rate during loading were calculated and compared with speed and gait. At speeds ranging from 4 to 16.5 m/s there was compression of the dorsomedial cortex of the metacarpus and the magnitude of compression and rate of compression were proportional to the speed of exercise. At the walk (2 m/s) tension was recorded in some strides. The mean maximum compressive strains in the 6 horses were −966 μstrain at 2 m/s; −1630 μstrain at 4 m/s; −2172 μstrain at 6 m/s; −2857 μstrain at 8 m/s; −3500 μstrain at 10 m/s; and −3911 μstrain at 12 m/s. Recordings from 3 horses gave a mean −5028 μstrain at 14 m/s. One horse gave a mean −6296 μstrain at 16.5 m/s. These strains were all about 25% higher than those recorded from the metacarpus of adult Thoroughbreds under similar exercise conditions. It was concluded that the higher strains may predispose the young Thoroughbred racehorse to do

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04868.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryThe objective of this study was to compare shoulder, elbow and carpus rotations bilaterally during the gallop in an investigation of intralimb coordination of the foreleg during high‐speed asymmetrical quadrupedal locomotion. The motion patterns of the forelimb during the gallop stride were documented using high‐speed cinematography. The gallop stride characteristics of 4 Quarter Horse fillies, approximately 30 months of age, were examined. Horses were housed and fed together and received the same amount and type of limited training, and were all ridden with the same tack by one person. Both sides of each horse were filmed simultaneously (243 frames/s) while galloping individually along a 1.5 m‐wide track. Kinematic variables describing 29 strides (16 left lead, 13 right lead; mean velocity 13.1 m/s, stride frequency 2.60 strides/s, stride length 5.06 m) included temporal and linear measurements of the approximate centres of rotation of the shoulder, elbow and carpal joints; maximum and minimum relative angles and angular velocities of those joints; and maximum and minimum angles with respect to the horizon of the scapula, humerus, radius and metacarpus segments. In both forelimbs, hoof impact was followed sequentially by maximal carpal extension and maximal elbow extension in weightbearing during the stance phase. Hoof lift‐off was followed sequentially by maximal carpal flexion, maximal shoulder flexion, maximal elbow flexion and simultaneous shoulder maximal extension and an initial extension peak of carpus well prior to hoof impact. Temporal patterns of forelimb motion at the gallop appear to originate proximal to the elbow joint. Distal to the shoulder joint, basic motion patterns are remarkably similar on the leading and trailing sides of the body. A high degree of reciprocity in shoulder joint action was observed, a mechanism contributing to the energetic economy of the equine

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04869.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryDrop tests were carried out on 8 Scandinavian harness racetracks in order to evaluate their shock force attenuation properties. A drop hammer model was designed to simulate the hoof strike of the horse. The analysis comprised calculations for mean hardness index, impact time and energy loss which were correlated to ground composition parameters. The range of hardness, impact time and energy loss was 246–366 s−1, 7.6–13.2 ms and 74–95%, respectively at the inner lane of the track when the fallheight 0.6 m was used. The corresponding data for an outer lane were 225–392 s−1, 8.2–13.4 ms and 78–93%. The study showed significant differences in hardness, impact time and energy absorption between racetracks and between different test areas along the same course, with the outer lane usually being the harder. The drop height 1.5 m simulated a higher hoof landing velocity but gave similar results.It is suggested that impact force influence from the ground may be detrimental to horses and significant effort should be made in track construction and management. It is postulated that tracks with adequate cushioning are likely to prevent excessive shock loading and related musculo‐skeletal disord

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04870.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryA method applicable for field studies of equine locomotion based on recordings by high‐speed cinematography/videography with a panning camera is presented. A ground reference plane/line was defined by a number of ground reference plates at equidistant intervals along the filming range. One ground reference plate in the middle of the range was predefined and designated as Ref0. The camera position was determined in such a way that the camera axis was perpendicular to the reference line when aiming towards Ref0. The maximum error introduced by the experimental setup was less than 3% and the perspective errors at the end of the recording range less than 0.02 m in a single position determination. The method was applied to study some basic temporal and linear variables and the pastern, metacarpal segment and fetlock joint angles in 6 young Standardbred trotters at 10.2 ± 0.17 m/s. The mean stride and stance durations for the group of horses were 503 ± 15 ms and 131 ± 6 ms, respectively. Indications of laterality in individual horses were observed when diagonal and contralateral pairs of limbs were studied. Sudden angle changes were observed in the fetlock segment and fetlock joint at full support following braking of the fore‐aft horizontal hoof mo

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04871.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY