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1.
Data Brief ; 56: 110799, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39252769

RESUMEN

Conformation traits are important in the selection and distinction between horse breeds, but tend to be evaluated subjectively within a breed and cannot be compared between them. The horse shape space model, using a combination of 253 landmarks and semi-landmarks, provides objective information on the shape of a horse photographed from the side that can be compared between breeds. In this dataset, we are providing the full set of 253 landmarks for 1241 horses from seven breeds, including an R code file to extract joint angle information and transform the raw data into csv files for further analysis, such as breed comparisons, heritability or genome-wide association studies (single- or multibreed). The repeatability of the joint angles are also reported.

2.
Data Brief ; 55: 110764, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39183964

RESUMEN

Horses have been used and bred for centuries for their movements. However, specific breeds are expected to have different movement capabilities. We have measured 425 horses from four different breeds at walk and trot on a straight line using an inertial measurement unit (IMU) system (EquiMoves®). This article describes how the data was collected, filtered and analysed to provide a useable dataset of 28 movement variables. It provides a full protocol for field measurements and requirements for adequate trials for analysis. Intra-class correlation coefficient estimates are also provided to assess repeatability of the measurements.

3.
Front Vet Sci ; 10: 1213423, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37404776

RESUMEN

Background: Although the temporomandibular joint (TMJ) is the major contact point between the reins in the riders' hand, the bit in the mouth, and the rest of the horse under saddle, the role of inflammation of this joint on equine locomotion and rein tension is unknown. Objective: To determine the effect of acute TMJ inflammation on rein-tension and horse movement when horses were long-reined on a treadmill. Study design: A randomized, controlled, cross-over design. Methods: Five horses were trained by one clinician to walk and trot on a treadmill wearing long-reining equipment instrumented with a rein-tension device and reflective optical tracking markers. Subjective assessment of horse's dominant side, and movement, were determined without rein-tension (free walk and trot); and with rein-tension (long-reined walk and trot). Continuous rein-force data from both sides were collected over ~60s from each trial. Movement was recorded using a 12-camera optical motion capture system. One randomly assigned TMJ was subsequently injected with lipopolysaccharide and the treadmill tests repeated by investigators blinded to treatment side. A second, identical assessment was performed 10 days later with the opposite TMJ being the target of intervention. Results: All horses showed reduced rein-tension on the injected (inflamed) side. Increased rein-tension was required on the non-injected side at trot, to maintain them in the correct position on the treadmill post-injection. The only kinematic variable to show any significant change due to rein tension or TMJ inflammation during the walk or trot was an increase in forward head tilt in the presence of rein tension in the trot after injection. Main limitations: Low number of horses and investigation of response to acute inflammation only. Conclusion: TMJ inflammation changed, subjectively and objectively, the response to rein-input, but the horses did not become lame.

4.
Animals (Basel) ; 13(21)2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37958159

RESUMEN

The public is increasingly questioning equestrianism's social license to operate. While the focus historically centered on horseracing, increased scrutiny is now being placed on how dressage, showjumping, and eventing are addressing equine management and welfare concerns. Nominated equestrian federation and equestrian organization experts (n = 104) directly involved in international and/or national-level horse sports took part in a four-stage, iterative Delphi to obtain consensus on what factors should be considered essential to manage sporthorse health and welfare. Five core domains were agreed as essential: training management, competition management, young horse management, health status and veterinary management, and the horse-human relationship. Two further domains: stable and environmental management, and welfare assessment were rated as important but not essential, as most respondents felt that these areas were already managed well. Participants felt increased education and guidance combined with further policy development and regulation are needed to support stakeholders to optimize sporthorse management. An appetite to engage with research to generate evidence that promotes sporthorse welfare was evident. The development of a sporthorse welfare charter and evidence-based guidelines to inform the management and monitoring of sporthorses' health and welfare are recommended to provide horses with a good life and to safeguard the future of equestrian sports.

5.
Data Brief ; 42: 108123, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35434226

RESUMEN

This article presents the data obtained from the scoring of 24 stallions of the Franches-Montagnes (FM) horse breed by six experts of this breed. The experts scored six traits at walk and eight at trot from the video recordings of these stallions walking and trotting on a treadmill during an incremental speed test. The scores were given on a scale of one to nine. All experts scored the same videos twice (two scoring tests) with a time interval of two years, and without feedback from the first scoring. Video sequences were presented in a different order between first and second scoring. The inter- and intra-rater reliability of the data was assessed using intraclass correlation coefficients (ICC) to evaluate its quality.

6.
J Equine Vet Sci ; 115: 104024, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35649491

RESUMEN

Ground coverage and over-tracking are two gait quality traits describing the forward movement of the front respectively the hind limbs in relation to stride length and over-tracking distance. To investigate the complex interplay of different movement patterns in ground coverage and over-tracking, limb and body kinematics of 24 Franches-Montagnes (FM) stallions were measured with 3D optical motion capture (OMC) on a treadmill during an incremental speed test at the walk (1.4-2.0 m/s). The significance and amount of explained variance of kinematic parameters on stride length and over-tracking distance were estimated using linear mixed-effect models, with speed and horse as random effects. Two separate models were tested: a full model with all parameters measurable by OMC, and a reduced model with a subset of parameters also measurable with inertial measurement units (IMUs). The kinematic parameters were correlated to the subjective scores from six breeding experts to interpret their external validity. The parameter for ground coverage at the walk, explaining most of the variance in stride length, were the maximal forelimb retraction angle (11%) measured with OMC, and the range of pelvis pitch (10%) if measuring with IMUs. The latter was also the most relevant for quantifying over-tracking, explaining 24% to 33% of the variance in the over-tracking distance. The scores from most breeding experts were significantly correlated (r ≥ |0.41|) with the fore- and hind limb protraction angles, which reflect the textual definition of ground coverage and over-tracking. Both gait quality traits can be objectively quantified using either OMC or IMUs.


Asunto(s)
Marcha , Caminata , Animales , Fenómenos Biomecánicos , Miembro Anterior , Miembro Posterior , Caballos , Masculino
7.
J Equine Vet Sci ; 99: 103388, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33781419

RESUMEN

Ill-fitting saddles can impair the well-being and performance of horses. Saddle fit is generally assessed subjectively by a trained professional or with an electronic saddle pressure mat, but little is known about the agreement between both methods. The study aims were (1) to assess the prevalence of saddle fit issues in a riding sound Swiss horse population, (2) to investigate how well the subjective assessment correlates with objectively measured pressure magnitude and distribution under the saddle during riding, and (3) how well both correlate with back pain of the horse. Only 10% of the saddles were free of the assessed problems. Pressures exceeded clinically relevant thresholds in 15% of the horses. There was no clear correlation between back pain and pressure magnitude, but back pain was associated with certain subjectively assessed fit problems. Statistically significant associations between fit problems and the expected pressure patterns were found for panel angles, curvature of the saddle, width of the panel channel, and the waist of the saddle. There was no or limited association of pressure patterns with the balance of the saddle, width and angle of the tree head, or the symmetry of the panels. The results revealed that certain fit problems were reflected in the electronically measured pressure distribution and that the subjective assessment can therefore provide relevant information. Pressure magnitude showed only limited association with back pain, which indicates that there are other factors involved in the development of back problems in horses.


Asunto(s)
Dolor de Espalda , Dorso , Marcha , Animales , Dolor de Espalda/diagnóstico , Dolor de Espalda/veterinaria , Fenómenos Biomecánicos , Caballos , Presión , Prevalencia , Suiza/epidemiología
8.
Equine Vet J ; 53(3): 600-611, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32888199

RESUMEN

BACKGROUND: There is a paucity of research describing the gait pattern of lame horses at the walk. OBJECTIVES: To describe the changes in motion pattern and vertical ground reaction forces (GRFz) in horses with induced forelimb lameness at the walk and compare those changes with the changes observed at the trot. STUDY DESIGN: Experimental study. METHODS: In 10 clinically sound Warmblood horses, moderate forelimb lameness was induced using a sole pressure model followed by trot and walk on a treadmill. Kinematic data were collected using 3D optical motion capture (OMC), and GRFz by an instrumented treadmill. Mixed models were used to compare sound baseline versus forelimb lameness (significance was set at P < .05). RESULTS: Lameness induction significantly reduced peak GRFz on the second force peak, and vertical impulse in the lame limb. Stride and stance duration in all limbs were reduced. Lameness significantly affected the vertical movement symmetry of the head and withers. Maximum limb retraction angle, fetlock extension and protraction speed were reduced in the lame limb. Body centre of mass (COM) translation was reduced in the side-to-side direction and increased in the vertical and fore-aft directions. Several compensatory kinetic and kinematic changes were observed in the nonlame limbs. The observed changes in both kinetics and kinematics were generally smaller at walk with fewer variables being affected, compared to the trot. MAIN LIMITATIONS: Only one degree and type of orthopaedic pain (sole pressure) was studied. CONCLUSIONS: Compensatory strategies of forelimb lameness at the walk include alteration of several kinetic and kinematic parameters and have some specific patterns and inter-individual differences that are not seen at the trot. However, much like at the trot, head movement and forelimb vertical force symmetry seem to be the most useful parameters to detect forelimb lameness at walk.


Asunto(s)
Enfermedades de los Caballos , Caminata , Animales , Fenómenos Biomecánicos , Miembro Anterior , Marcha , Miembro Posterior , Caballos , Cojera Animal/diagnóstico
9.
Equine Vet J ; 53(1): 157-166, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32125717

RESUMEN

BACKGROUND: Left-right movement symmetry is a highly desirable characteristic in sport horses. OBJECTIVES: This study compared movement symmetry in well-trained dressage horses in unridden and unrestrained position and ridden in a dressage frame, and investigated possible associations between gaits. STUDY DESIGN: Experimental study. METHODS: Seven sound, high-level dressage horses were measured at walk and sitting trot on a treadmill at several speeds under two conditions: with and without rider. Left-right differences in stance duration, stance protraction and retraction based on longitudinal hoof positions, ipsilateral limb tracking, minimum and maximum vertical positions of the dorsal spinous processes of the sixth thoracic (T6), third sacral vertebrae (S3) and wing of atlas, and vertical ground reaction forces were calculated and analysed in mixed models. RESULTS: At walk, five body variables indicated increased asymmetry in the ridden condition compared with unridden condition: forelimb stance duration (unridden/ridden left-right differences 9 vs 13 ms; P = .008), forelimb stance protraction (P = .004), stance retraction (P = .001) and first force peak (P = .003), and hindlimb stance retraction (P = .01). At trot, six body variables were more asymmetrical in the ridden condition: forelimb stance duration (2.5 vs 3.8 ms, P = .004); hindlimb stance protraction (P < .0001) and retraction (P = .01), T6 minimum (4 vs 6 mm, P = .001), T6 maximum (9 vs 11 mm, P = .01) and S3 maximum (6 vs 12 mm, P < .001). Five variables had significant associations between asymmetries at walk and trot, but only three demonstrated a positive slope. MAIN LIMITATIONS: A limited number of horses and riders were studied. Measurements were performed on a treadmill. CONCLUSIONS: High-level horses moved slightly more asymmetrically when ridden in a dressage frame than in the unridden condition.


Asunto(s)
Miembro Anterior , Caminata , Animales , Fenómenos Biomecánicos , Marcha , Miembro Posterior , Caballos
10.
J Equine Vet Sci ; 95: 103314, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33276930

RESUMEN

Lameness is a symptom indicative of pain or injury of the locomotor apparatus. Lame horses generally should not be ridden. However, owners' ability to assess lameness has been questioned. This study's aim was to use subjective lameness assessments and objective gait analysis to generate a descriptive overview of movement and weight-bearing asymmetries of owner-sound riding horses. 235 horses were subjectively assessed in a field study, and the owner's perception of their horse's orthopedic health was recorded through an online survey. 69 horses were re-evaluated by gait analysis at an equine hospital. During trot on an instrumented treadmill, the gait was scored by a veterinarian using lameness grades from 0/5 (sound) to 3/5 (moderate lameness visible at trot). Movement asymmetry of the head (HDmin) and pelvis (PDmin) and weight-bearing asymmetry were quantified simultaneously. The prevalence of subjectively scored lameness grade ≥2/5 in one or more limbs was 55% during study part 1 and 74% during study part 2. Movement asymmetry of the head and/or pelvis exceeding HDmin ≥12 mm and/or PDmin ≥6 mm was found in 57% of the horses. 58% showed weight-bearing asymmetries between contralateral front and/or hind limbs of ≥3% body mass. Gait analysis showed considerable variability of movement and weight-bearing asymmetry values, sometimes independent of the clinical lameness grade, especially in the forehand. Several horses with lameness grade ≤1/5 had asymmetry values greater than mentioned thresholds. The analysis of movement and weight-bearing asymmetry revealed that these objective variables did not necessarily act uniformly and therefore should be interpreted with caution.


Asunto(s)
Enfermedades de los Caballos , Cojera Animal , Animales , Fenómenos Biomecánicos , Miembro Anterior , Marcha , Miembro Posterior , Enfermedades de los Caballos/diagnóstico , Caballos , Cojera Animal/diagnóstico
11.
J Equine Vet Sci ; 91: 103107, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32684252

RESUMEN

The use of horses in competitive sports receives increasing criticism from the public, mainly due to the potential for injury. However, it is unclear if orthopedic and other health issues are more common in competition horses than those in leisure horses. The aim of this study was to assess husbandry, use, and orthopedic health in Swiss riding horses and to compare these aspects between horses owned by self-identified competitive riders (CR) and leisure riders (LR) in Switzerland. A total of 237 owners completed an online survey providing information on their athletic ambitions, their horse's husbandry, health, training, and tack. Two experienced veterinarians assessed gait irregularities, muscular development, and back pain in the horses and evaluated saddle fit. Compared with horses owned by competitive riders (CH), a higher proportion of horses kept by leisure riders (LH) were kept unshod, under more natural conditions, and turned out with other horses. LH were exercised less frequently, and LR trained less frequently with instructors. CR reported less time since the last saddle check and the use of more training aids during riding. No differences between the two groups could be found in orthopedic health, muscular development, or back pain, but LH had higher body condition scores and a slightly higher proportion of saddles with at least one fit problem. Our data revealed no increased prevalence of the assessed health problems in competition horses compared with leisure horses in Switzerland. However, suboptimal saddle fit and muscular development, back pain, and gait irregularity are frequent in both groups and deserve more attention.


Asunto(s)
Deportes , Animales , Dolor de Espalda/epidemiología , Dolor de Espalda/veterinaria , Marcha , Caballos , Encuestas y Cuestionarios , Suiza/epidemiología
12.
Vet J ; 181(2): 151-7, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18424198

RESUMEN

To evaluate the manner in which a cow's claws make contact with the ground at the walk, the gait, and in particular the claw-ground contact pattern, were studied in 12 healthy, lactating dairy cows, using high-speed cinematography (500frames/s) while the animals were walking on a treadmill. The results showed that the limbs were advanced around the contralateral limbs in a sigmoid curve. The feet contacted the ground with the foot axis and the tips of the claws rotated slightly outwards. In all cows the lateral claws contacted the ground before the medial claws in the hindlimbs, and in 10/12 cows in the forelimbs. The heel of the lateral claws was the region of initial contact with the ground in the hindlimbs of all cows and in the forelimbs in 9/12 cows. Lateral 'heel first' contact in the fore and hindlimbs appeared to be the normal gait pattern in these animals. Compared with a previous study of heifers, lactating cows had a larger step width in the hindlimbs and a smaller step width in the forelimbs. These ground contact patterns offer an explanation for the predisposition to claw disorders of the lateral claw of the hindlimb. The results of this study reinforce the suggestion that soft floor surfaces should be provided for cattle to prevent mechanical injury to the claws.


Asunto(s)
Marcha/fisiología , Pezuñas y Garras/fisiología , Lactancia/fisiología , Películas Cinematográficas , Caminata/fisiología , Animales , Huesos/fisiología , Bovinos , Femenino , Lateralidad Funcional
13.
Vet J ; 179(1): 50-9, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18069025

RESUMEN

Extracorporeal shock wave therapy (ESWT) is an accepted form of treatment for chronic cases of proximal suspensory desmitis (PSD). Subjective evaluation of horses shortly after being treated with ESWT has led clinicians to comment on an immediate reduction in lameness. This study aimed to evaluate the analgesic effect of ESWT on 16 horses with PSD or PSD-like pain in a fore- or hindlimb. To objectively assess lameness, gait analysis was performed on an instrumented treadmill before and 6, 24, 48 and 72h after ESWT of the origin of the suspensory ligament and the results compared to the effects of local anaesthesia. Stride frequency, stance duration, vertical impulse and peak vertical force were determined. Thermographic imaging and evaluation of skin sensitivity of the treated area were carried out before and after ESWT in the same interval as gait analysis. The results showed that there were no significant improvements in the investigated parameters at any time after ESWT; however, in horses with affected forelimbs the contralateral weightbearing asymmetry decreased significantly 72h after ESWT. Neither skin sensitivity nor thermographic imaging revealed changes that could be attributed to ESWT.


Asunto(s)
Analgesia/veterinaria , Ondas de Choque de Alta Energía/uso terapéutico , Enfermedades de los Caballos/terapia , Dolor/veterinaria , Analgesia/métodos , Animales , Femenino , Miembro Anterior , Miembro Posterior , Caballos , Cojera Animal/terapia , Ligamentos Articulares/patología , Masculino , Metacarpo/patología , Metatarso/patología , Manejo del Dolor , Resultado del Tratamiento
14.
J Equine Vet Sci ; 78: 20-28, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31203980

RESUMEN

Asymmetric forces exerted on the horse's back during riding are assumed to have a negative effect on rider-horse interaction, athletic performance, and health of the horse. Visualized on a saddle pressure mat, they are initially blamed on a nonfitting saddle. The contribution of horse and rider to an asymmetric loading pattern, however, is not well understood. The aim of this study was to investigate the effects of horse and rider asymmetries during stance and in sitting trot on the force distribution on the horse's back using a saddle pressure mat and motion capture analysis simultaneously. Data of 80 horse-rider pairs (HRP) were collected and analyzed using linear (mixed) models to determine the influence of rider and horse variables on asymmetric force distribution. Results showed high variation between HRP. Both rider and horse variables revealed significant relationships to asymmetric saddle force distribution (P < .001). During sitting trot, the collapse of the rider in one hip increased the force on the contralateral side, and the tilt of the rider's upper body to one side led to more force on the same side of the pressure mat. Analyzing different subsets of data revealed that rider posture as well as horse movements and conformation can cause an asymmetric force distribution. Because neither horse nor rider movement can be assessed independently during riding, the interpretation of an asymmetric force distribution on the saddle pressure mat remains challenging, and all contributing factors (horse, rider, saddle) need to be considered.


Asunto(s)
Dorso , Sedestación , Animales , Fenómenos Biomecánicos , Caballos , Movimiento , Postura
15.
Vet Clin North Am Equine Pract ; 24(1): 79-100, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18314037

RESUMEN

The skill to diagnose lameness in horses is paramount for every equine practitioner. Early recognition of locomotor deficiencies plays a central role in sports medicine management, preventing deterioration of the disease or catastrophic injuries. Horses use characteristic compensatory movements of specific body parts to decrease loading of the affected limb. This article describes the underlying changes in intra- and interlimb coordination and the resulting load redistribution between the limbs. This enables the practitioner to better understand the changes in movement associated with lameness.


Asunto(s)
Adaptación Fisiológica , Enfermedades de los Caballos/fisiopatología , Caballos/lesiones , Cojera Animal/fisiopatología , Soporte de Peso , Animales , Estrés Mecánico , Soporte de Peso/fisiología
16.
PLoS One ; 13(9): e0204548, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30261019

RESUMEN

The walk and trot are inherently symmetrical gaits, making them potentially suitable for the detection of left-right asymmetries. The aims of this study were to describe asymmetrical vertical excursions of the withers at walk in non-lame high-level dressage horses and to seek associations between these asymmetric movements and other kinematic variables and vertical ground reaction forces (vGRFs). Seven dressage horses, judged clinically as being sound, walked unridden and unrestrained on a treadmill with an integrated force measuring system (480 Hz), from which spatiotemporal and vGRF variables were extracted. Markers were tracked by 12 infrared cameras (240 Hz). The vertical position of the sixth thoracic vertebra (T6), limb protraction and retraction distances throughout stance, and global limb lengths were determined. Contralateral trial-mean differences were calculated, including difference in T6 minimum vertical position between contralateral steps (T6minDiff). Mixed models were used to study associations between symmetry parameters. Trial-mean T6minDiff ranged between 0.3-23 mm. Of the seven horses, five consistently dropped the withers more in early left forelimb stance, one was fairly symmetrical, and one dropped the withers more in early right forelimb stance. Comparisons between contralateral limbs showed the following associations. The forelimb that was retracted when T6min was lowest showed greater retraction at toe-off (1 mm increase predicted 0.17 mm T6minDiff increase) and shorter stance duration (1 ms decrease predicted 0.3 mm T6minDiff increase). The hind limb that was in midstance when T6min was lowest showed a greater range of motion during the stance phase (1 mm increase in protraction or retraction predicted 0.2 mm T6minDiff increase). The haunches were displaced away from the side of the forelimb that was protracted when T6min was lowest (1 mm lateral shift predicted 0.07 mm T6minDiff increase). Forelimb and hind limb vGRF parameters were non-significant. Asymmetry of vertical withers movement in horses assessed as being sound at trot was related to a complex pattern of asymmetries in spatiotemporal variables throughout the stride cycle rather than to vertical load redistribution between the forelimbs. This suggests that the asymmetry may be due to inherent laterality rather than weight-bearing lameness.


Asunto(s)
Marcha/fisiología , Caballos/fisiología , Animales , Fenómenos Biomecánicos , Marcadores Fiduciales , Miembro Anterior/fisiología , Miembro Posterior/fisiología , Caballos/anatomía & histología , Modelos Biológicos , Caminata/fisiología
17.
Vet J ; 171(1): 135-46, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15974567

RESUMEN

The study was performed to obtain a detailed insight into the load and time shifting mechanisms of horses with unilateral weight-bearing forelimb lameness. Reversible lameness was induced in 11 clinically sound horses by applying a solar pressure model. Three degrees of lameness (subtle, mild and moderate) were induced and compared with sound control measurements. Vertical ground reaction force-time histories of all four limbs were recorded simultaneously on an instrumented treadmill. Four compensatory mechanisms could be identified that served to reduce structural stress, i.e. peak vertical force on the affected limb: (1) with increasing lameness, horses reduced the total vertical impulse per stride; (2) the diagonal impulse decreased selectively in the lame diagonal; (3) the impulse was shifted within the lame diagonal to the hindlimb and in the sound diagonal to the forelimb; (4) the rate of loading and the peak forces were reduced by prolonging the stance duration. Except in the diagonal hindlimb, where peak vertical forces increased slightly in the moderate lameness condition, no equivalent compensatory overload situation was observed in the other limbs. Specific force and time information of all four limbs allow the unequivocal identification of the affected limb.


Asunto(s)
Enfermedades de los Caballos/fisiopatología , Caballos/fisiología , Cojera Animal/fisiopatología , Soporte de Peso/fisiología , Adaptación Fisiológica , Animales , Prueba de Esfuerzo/veterinaria , Miembro Anterior
18.
J Comput Nonlinear Dyn ; 11(2): 0210081-2100812, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27222653

RESUMEN

This paper presents a simplistic passive dynamic model that is able to create realistic quadrupedal walking, tölting, and trotting motions. The model is inspired by the bipedal spring loaded inverted pendulum (SLIP) model and consists of a distributed mass on four massless legs. Each of the legs is either in ground contact, retracted for swing, or is ready for touch down with a predefined angle of attack. Different gaits, that is, periodic motions differing in interlimb coordination patterns, are generated by choosing different initial model states. Contact patterns and ground reaction forces (GRFs) evolve solely from these initial conditions. By identifying appropriate system parameters in an optimization framework, the model is able to closely match experimentally recorded vertical GRFs of walking and trotting of Warmblood horses, and of tölting of Icelandic horses. In a detailed study, we investigated the sensitivity of the obtained solutions with respect to all states and parameters and quantified the improvement in fitting GRF by including an additional head and neck segment. Our work suggests that quadrupedal gaits are merely different dynamic modes of the same structural system and that we can interpret different gaits as different nonlinear elastic oscillations that propel an animal forward.

19.
Am J Vet Res ; 66(12): 2095-100, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16379653

RESUMEN

OBJECTIVE: To evaluate the effects of shock wave treatment on cutaneous nerve function, compared with the effects of local nerve block and sedation. ANIMALS: 18 clinically sound Swiss Warmbloods. PROCEDURE: Horses were randomly allocated to 3 groups and received different amounts and types of shock waves (extracorporeal shock wave treatment [ESWT] or radial pressure wave treatment [RPWT]). Horses were sedated with xylazine and levomethadone. Shock waves were applied to the lateral palmar digital nerve at the level of the proximal sesamoid bones on 1 forelimb. Skin sensitivity was evaluated by means of an electrical stimulus at the coronary band before and 5 minutes after sedation and at 4, 24, and 48 hours after application of ESWT or RPWT. On the contralateral forelimb, skin sensitivity was tested before and 10 minutes after an abaxial sesamoid nerve block. RESULTS: No significant changes in skin sensitivity were detected, regardless of the shock wave protocol applied. Mean reaction thresholds after sedation were more than twice the baseline thresholds. After the abaxial sesamoid block, no reaction was recorded in any of the horses. CONCLUSIONS AND CLINICAL RELEVANCE: Application of ESWT or RPWT to the palmar digital nerve had no effect on cutaneous sensation distal to the treated region for at least 2 days after application. The analgesic effect of sedation on reaction to electrical stimuli was distinct but varied among horses.


Asunto(s)
Analgesia/veterinaria , Miembro Anterior/inervación , Ondas de Choque de Alta Energía , Nervios Periféricos/fisiología , Piel/inervación , Analgesia/métodos , Animales , Estimulación Eléctrica , Caballos , Bloqueo Nervioso/veterinaria , Umbral del Dolor/fisiología
20.
Am J Vet Res ; 76(12): 1031-40, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26618727

RESUMEN

OBJECTIVE: To compare gait mechanics and limb loading in Icelandic horses tölting and trotting at equal speeds and estimate their impact on orthopedic health. ANIMALS: 12 orthopedically normal Icelandic horses. PROCEDURES Kinetic and kinematic gait variables were simultaneously recorded as each horse was ridden at a tölt and trot on an instrumented treadmill at 3.4 m/s and 3.9 m/s. Differences between gaits were tested via 1-factor repeated-measures ANOVA. RESULTS: Horses had a higher stride rate and lower stride impulses at a tölt than at a trot. For forelimbs at a tölt, shorter relative stance duration resulted in higher peak vertical force (Fz(peak)). Conversely, for hind limbs, longer relative stance duration resulted in lower Fz(peak). The higher head-neck position at a tölt versus trot caused no weight shift to the hind limbs, but a higher forehoof flight arc and lower proretraction movement were identified. Stance durations for forelimbs were briefer than for hind limbs at a tölt, and the inverse was observed at a trot. Minimal height of the horse's trunk at the point of Fz(peak) of the respective limb suggested a spring-like mechanism for all limbs at a tölt. Hind limb measurements revealed no evidence of increased collection. Stride-to-stride limb timing varied more at a tölt than at a trot. At a trot, horses had brief or no suspension phases and a slightly 4-beated footfall rhythm was common. Post hoc energetic estimations revealed that tölting at the measured speeds was less advantageous than trotting. CONCLUSIONS AND CLINICAL RELEVANCE: High forelimb action in Icelandic horses and higher head-neck position at a tölt were associated with more restricted limb proretraction, higher Fz(peak), and faster force onset than at a trot. The impact of these differences on orthopedic health needs to be investigated more in detail.


Asunto(s)
Miembro Anterior/fisiología , Marcha , Miembro Posterior/fisiología , Caballos/fisiología , Animales , Fenómenos Biomecánicos , Peso Corporal , Femenino , Locomoción , Masculino , Torso
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