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Spadavecchia, C.; Arendt-Nielsen, L.; Spadavecchia, L.; Mosing, M.; Auer, U.; van den Hoven, R. |
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Title |
Effects of butorphanol on the withdrawal reflex using threshold, suprathreshold and repeated subthreshold electrical stimuli in conscious horses |
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Journal Article |
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Year |
2007 |
Publication |
Veterinary anaesthesia and analgesia |
Abbreviated Journal |
Vet Anaesth Analg |
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Volume |
34 |
Issue |
1 |
Pages |
48-58 |
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Keywords |
Analgesics, Opioid/pharmacology; Animals; Butorphanol/*pharmacology; Consciousness; Electric Stimulation; Electromyography; Female; Forelimb/physiology; Horses/*physiology; Male; Pain/veterinary; Pain Threshold/*drug effects; Reflex/*drug effects |
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Abstract |
OBJECTIVE: To assess the effects of a single intravenous dose of butorphanol (0.1 mg kg(-1)) on the nociceptive withdrawal reflex (NWR) using threshold, suprathreshold and repeated subthreshold electrical stimuli in conscious horses. STUDY DESIGN: 'Unblinded', prospective experimental study. ANIMALS: Ten adult horses, five geldings and five mares, mean body mass 517 kg (range 487-569 kg). METHODS: The NWR was elicited using single transcutaneous electrical stimulation of the palmar digital nerve. Repeated stimulations were applied to evoke temporal summation. Surface electromyography was performed to record and quantify the responses of the common digital extensor muscle to stimulation and behavioural reactions were scored. Before butorphanol administration and at fixed time points up to 2 hours after injection, baseline threshold intensities for NWR and temporal summation were defined and single suprathreshold stimulations applied. Friedman repeated-measures analysis of variance on ranks and Wilcoxon signed-rank test were used with the Student-Newman-Keul's method applied post-hoc. The level of significance (alpha) was set at 0.05. RESULTS: Butorphanol did not modify either the thresholds for NWR and temporal summation or the reaction scores, but the difference between suprathreshold and threshold reflex amplitudes was reduced when single stimulation was applied. Upon repeated stimulation after butorphanol administration, a significant decrease in the relative amplitude was calculated for both the 30-80 and the 80-200 millisecond intervals after each stimulus, and for the whole post-stimulation interval in the right thoracic limb. In the left thoracic limb a decrease in the relative amplitude was found only in the 30-80 millisecond epoch. CONCLUSION: Butorphanol at 0.1 mg kg(-1) has no direct action on spinal Adelta nociceptive activity but may have some supraspinal effects that reduce the gain of the nociceptive system. CLINICAL RELEVANCE: Butorphanol has minimal effect on sharp immediate Adelta-mediated pain but may alter spinal processing and decrease the delayed sensations of pain. |
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Anesthesiology Section, Department of Clinical Veterinary Sciences, Vetsuisse Faculty, University of Berne, Berne, Switzerland. claudia.spadavecchia@veths.no |
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1467-2987 |
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PMID:17238962 |
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Call Number |
refbase @ user @ |
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92 |
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Spadavecchia, C.; Arendt-Nielsen, L.; Andersen, O.K.; Spadavecchia, L.; Doherr, M.; Schatzmann, U. |
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Title |
Comparison of nociceptive withdrawal reflexes and recruitment curves between the forelimbs and hind limbs in conscious horses |
Type |
Journal Article |
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Year |
2003 |
Publication |
American journal of veterinary research |
Abbreviated Journal |
Am J Vet Res |
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Volume |
64 |
Issue |
6 |
Pages |
700-707 |
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Keywords |
Animals; Consciousness; Female; Forelimb/*physiology; Hindlimb/*physiology; Horses/*physiology; Male; Nociceptors/physiology; Pain/*physiopathology/*veterinary; Pain Threshold/physiology; Recruitment, Neurophysiological/physiology; Reflex/*physiology |
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OBJECTIVE: To compare nociceptive withdrawal reflexes (NWRs) evoked from the distal aspect of the left forelimb and hind limb in conscious standing horses and to investigate NWR recruitment for graded electrical stimulation intensities. ANIMALS: 20 adult horses. PROCEDURE: Surface electromyographic (EMG) activity evoked by transcutaneous electrical stimulation of the digital palmar (or plantar) nerve was recorded from the common digital extensor and cranial tibial muscles. Stimuli consisted of 25-millisecond train-of-5 constant current pulses. Current intensity was gradually increased until NWR threshold intensity was reached. The EMG signal was analyzed for quantification of the NWR. Behavioral responses accompanying the reflex were scored (scale, 0 to 5). The NWR recruitment curves were determined at 0.9, 1.1, 1.2, and 1.3 times the NWR threshold intensity. RESULTS: The NWR threshold was significantly higher for the hind limb (median value, 6.6 mA; range, 3 to 10 mA) than the forelimb (median, 3 mA; range, 1.7 to 5.5 mA). The NWR of the hind limb had a significantly longer latency (median, 122.8 milliseconds; range, 106 to 172 milliseconds), compared with the forelimb (median, 98 milliseconds; range, 86 to 137 milliseconds), and it was associated with significantly stronger behavioral reactions. Gradual increase of NWR amplitude was evident at increasing stimulation intensities and supported by the behavioral observations. CONCLUSIONS AND CLINICAL RELEVANCE: We documented NWRs evoked from the forelimb and hind limb and their recruitment with stimuli of increasing intensity in horses. These results provide a basis for use of NWRs in studies on nociceptive modulation in horses. |
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Department of Clinical Veterinary Sciences, University of Berne, Switzerland |
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0002-9645 |
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PMID:12828255 |
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refbase @ user @ |
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93 |
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Kraus-Hansen, A.E.; Fackelman, G.E.; Becker, C.; Williams, R.M.; Pipers, F.S. |
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Title |
Preliminary studies on the vascular anatomy of the equine superficial digital flexor tendon |
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Journal Article |
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Year |
1992 |
Publication |
Equine veterinary journal |
Abbreviated Journal |
Equine Vet J |
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24 |
Issue |
1 |
Pages |
46-51 |
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Angiography/veterinary; Animals; Exercise Test/veterinary; Forelimb; Horses/*anatomy & histology/surgery; Microcirculation; Microscopy, Electron, Scanning; Tendons/*blood supply/surgery/ultrastructure |
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The vascular and microvascular anatomy of normal equine superficial digital flexor tendons was studied by dissection of vinyl-perfused specimens and by microangiography on high detail film. The presence of an extensive intratendinous vascular latticework was confirmed, and a 'nutrient artery' described closely associated with the accessory ligament of the superficial digital flexor tendon (proximal check ligament). Circumferential stripping of the paratenon from the tendon to eliminate afferent vessels was performed bilaterally in three horses and unilaterally in a fourth, followed by a treadmill training regimen. No resulting intratendinous lesions could be documented on gross post mortem and histological examination at three, 10, or 35 days post operatively. There was mild paratendinous proliferation in all instances. In one horse, four intratendinous ligatures were placed within the medial and lateral borders of the contralateral tendon to isolate further from its blood supply a 10 cm segment. Gross lesions at 35 days post operatively included a marked paratendinous response involving the entire 10 cm segment, and a darkened, soft focus within the core of the tendon. Histopathology and electron microscopy demonstrated focal degeneration. It was concluded that the blood supply of the normal equine superficial digital flexor tendon is primarily intratendinous, rather than paratendinous as previously thought. The lesions in one horse similar to those in naturally occurring tendinitis supported a vascular aetiology of the disease, and set the groundwork for studies aimed at the development of a clinically relevant tendinitis model. |
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Department of Surgery, Tufts University School of Veterinary Medicine, North Grafton, Massachusetts 01536 |
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0425-1644 |
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PMID:1555540 |
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refbase @ user @ |
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151 |
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van Heel, M.C.V.; Kroekenstoel, A.M.; van Dierendonck, M.C.; van Weeren, P.R.; Back, W. |
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Title |
Uneven feet in a foal may develop as a consequence of lateral grazing behaviour induced by conformational traits |
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Journal Article |
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Year |
2006 |
Publication |
Equine veterinary journal |
Abbreviated Journal |
Equine. Vet. J. |
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38 |
Issue |
7 |
Pages |
646-651 |
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Aging/*physiology; Animals; Animals, Newborn/anatomy & histology/growth & development/physiology; Feeding Behavior/*physiology; Female; Forelimb/*anatomy & histology/*physiology; *Horses/anatomy & histology/growth & development/physiology; Male |
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REASONS FOR PERFORMING STUDY: Conformational traits are important in breeding, since they may be indicative for performance ability and susceptibility to injuries. OBJECTIVES: To study whether certain desired conformational traits of foals are related to lateralised behaviour while foraging and to the development of uneven feet. METHODS: Twenty-four Warmblood foals, born and raised at the same location, were studied for a year. Foraging behaviour was observed by means of weekly 10 min scan-sampling for 8 h. A preference test (PT) was developed to serve as a standardised tool to determine laterality. The foals were evaluated at age 3, 15, 27 and 55 weeks. The PT and distal limb conformation were used to study the relation between overall body conformation, laterality and the development of uneven feet. Pressure measurements were used to determine the loading patterns under the feet. RESULTS: About 50% of the foals developed a significant preference to protract the same limb systematically while grazing, which resulted in uneven feet and subsequently uneven loading patterns. Foals with relatively long limbs and small heads were predisposed to develop laterality and, consequently unevenness. CONCLUSIONS: Conformational traits may stimulate the development of laterality and therefore indirectly cause uneven feet. |
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Derona Equine Performance Laboratory, Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 12, NL-3584 CM Utrecht, The Netherlands |
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0425-1644 |
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PMID:17228580 |
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1774 |
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Scheibe, K.M.; Gromann, C. |
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Application testing of a new three-dimensional acceleration measuring system with wireless data transfer (WAS) for behavior analysis |
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2006 |
Publication |
Behavior research methods |
Abbreviated Journal |
Behav Res Methods |
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38 |
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3 |
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427-433 |
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Acceleration; Animals; *Behavior, Animal; Cattle; Cattle Diseases/*diagnosis; Computer Communication Networks/*instrumentation; Forelimb/physiopathology; Fractals; Hindlimb/physiopathology; Horse Diseases/*diagnosis; Horses; Imaging, Three-Dimensional/instrumentation/methods/veterinary; Lameness, Animal/*diagnosis; Monitoring, Ambulatory/instrumentation/*methods; Motor Activity; Movement; Pattern Recognition, Automated/methods |
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A wireless acceleration measurement system was applied to free-moving cows and horses. Sensors were available as a collar and a flat box for measuring leg or trunk movements. Results were transmitted simultaneously by radio or stored in an 8-MB internal memory. As analytical procedures, frequency distributions with standard deviations, spectral analyses, and fractal analyses were applied. Bymeans of the collar sensor, basic behavior patterns (standing, grazing, walking, ruminating, drinking, and hay uptake) could be identified in cows. Lameness could be detected in cows and horses by means of the leg sensor. The portion of basic and harmonic spectral components was reduced; the fractal dimension was reduced. The system can be used for the detection and analysis of even small movements of free-moving humans or animals over several hours. It is convenient for the analysis of basic behaviors, emotional reactions, or events causing flight or fright or for comparing different housing elements, such as floors or fences. |
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Institute for Zoo and Wildlife Research, Berlin, Germany. kscheibe@izw-berlin.de |
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1554-351X |
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PMID:17186752 |
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1775 |
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McGreevy, P.D.; Rogers, L.J. |
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Title |
Motor and sensory laterality in thoroughbred horses |
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Journal Article |
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Year |
2005 |
Publication |
Applied Animal Behaviour Science |
Abbreviated Journal |
Appl. Anim. Behav. Sci. |
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Volume |
92 |
Issue |
4 |
Pages |
337-352 |
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Horse; Lateralisation; Training; Olfaction; Forelimb preference |
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We investigated lateralisation in horses because it is likely to be important in training and athletic performance. Thoroughbred horses (n = 106) were observed every 60 s for 2 h, when they were at pasture, and the position of the forelimbs in relation to one another was recorded. There was a population bias skewed to standing with the left forelimb advanced over the right (i.e. directional lateralisation). Using the first 50 observations, the distribution of preferences was 43 significantly left, 10 significantly right with 53 being non-significant (i.e. ambidextextrous). The strength of motor bias increased with age, suggesting maturation or an influence of training. The horses were also presented with an olfactory stimulus (stallion faeces) to score the tendency to use one nostril rather than the other. A significant preference to use the right nostril first was shown in horses under 4 years of age (n = 61) but not in older horses. Of the 157 horses tested for nostril bias, 76 had been assessed for motor bias and so were used for analysis of the relationship between laterality in the two modalities. There was no significant relationship between direction of foreleg motor bias and first nostril used, total number of inhalations or laterality index of nostril use. The absence of a correlation between laterality of nostril use and motor bias indicates that lateralisation of the equine brain occurs on at least two levels of neural organisation--sensory and motor--a finding that is consistent with other examples of lateralisation in species that have been examined in more detail. |
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Equine Behaviour @ team @ room 3.029 |
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1827 |
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Skedros, J.G.; Dayton, M.R.; Sybrowsky, C.L.; Bloebaum, R.D.; Bachus, K.N. |
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The influence of collagen fiber orientation and other histocompositional characteristics on the mechanical properties of equine cortical bone |
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Journal Article |
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2006 |
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The Journal of Experimental Biology |
Abbreviated Journal |
J Exp Biol |
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Volume |
209 |
Issue |
Pt 15 |
Pages |
3025-3042 |
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Animals; Biomechanics; Bone and Bones/*physiology; Collagen/*physiology; Forelimb; Horses/*physiology |
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This study examined relative influences of predominant collagen fiber orientation (CFO), mineralization (% ash), and other microstructural characteristics on the mechanical properties of equine cortical bone. Using strain-mode-specific (S-M-S) testing (compression testing of bone habitually loaded in compression; tension testing of bone habitually loaded in tension), the relative mechanical importance of CFO and other material characteristics were examined in equine third metacarpals (MC3s). This model was chosen since it had a consistent non-uniform strain distribution estimated by finite element analysis (FEA) near mid-diaphysis of a thoroughbred horse, net tension in the dorsal/lateral cortices and net compression in the palmar/medial cortices. Bone specimens from regions habitually loaded in tension or compression were: (1) tested to failure in both axial compression and tension in order to contrast S-M-S vs non-S-M-S behavior, and (2) analyzed for CFO, % ash, porosity, fractional area of secondary osteonal bone, osteon cross-sectional area, and population densities of secondary osteons and osteocyte lacunae. Multivariate multiple regression analyses revealed that in S-M-S compression testing, CFO most strongly influenced total energy (pre-yield elastic energy plus post-yield plastic energy); in S-M-S tension testing CFO most strongly influenced post-yield energy and total energy. CFO was less important in explaining S-M-S elastic modulus, and yield and ultimate stress. Therefore, in S-M-S loading CFO appears to be important in influencing energy absorption, whereas the other characteristics have a more dominant influence in elastic modulus, pre-yield behavior and strength. These data generally support the hypothesis that differentially affecting S-M-S energy absorption may be an important consequence of regional histocompositional heterogeneity in the equine MC3. Data inconsistent with the hypothesis, including the lack of highly longitudinal collagen in the dorsal-lateral ;tension' region, paradoxical histologic organization in some locations, and lack of significantly improved S-M-S properties in some locations, might reflect the absence of a similar habitual strain distribution in all bones. An alternative strain distribution based on in vivo strain measurements, without FEA, on non-Thoroughbreds showing net compression along the dorsal-palmar axis might be more characteristic of the habitual loading of some of the bones that we examined. In turn, some inconsistencies might also reflect the complex torsion/bending loading regime that the MC3 sustains when the animal undergoes a variety of gaits and activities, which may be representative of only a portion of our animals, again reflecting the possibility that not all of the bones examined had similar habitual loading histories. |
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Utah Bone and Joint Center, 5323 S. Woodrow Street #202, Salt Lake City, UT 84107, USA. jskedros@utahboneandjoint.com |
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0022-0949 |
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PMID:16857886 |
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1868 |
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Author |
Bobbert, M.F.; Santamaria, S. |
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Contribution of the forelimbs and hindlimbs of the horse to mechanical energy changes in jumping |
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Journal Article |
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2005 |
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The Journal of Experimental Biology |
Abbreviated Journal |
J Exp Biol |
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Volume |
208 |
Issue |
2 |
Pages |
249-260 |
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Animals; Biomechanics; Forelimb/*physiology; Hindlimb/*physiology; Horses/*physiology; Locomotion/*physiology; Muscle, Skeletal/*physiology; Time Factors |
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The purpose of the present study was to gain more insight into the contribution of the forelimbs and hindlimbs of the horse to energy changes during the push-off for a jump. For this purpose, we collected kinematic data at 240 Hz from 23 5-year-old Warmbloods (average mass: 595 kg) performing free jumps over a 1.15 m high fence. From these data, we calculated the changes in mechanical energy and the changes in limb length and joint angles. The force carried by the forelimbs and the amount of energy stored was estimated from the distance between elbow and hoof, assuming that this part of the leg behaved as a linear spring. During the forelimb push, the total energy first decreased by 3.2 J kg(-1) and then increased again by 4.2 J kg(-1) to the end of the forelimb push. At the end of the forelimb push, the kinetic energy due to horizontal velocity of the centre of mass was 1.6 J kg(-1) less than at the start, while the effective energy (energy contributing to jump height) was 2.3 J kg(-1) greater. It was investigated to what extent these changes could involve passive spring-like behaviour of the forelimbs. The amount of energy stored and re-utilized in the distal tendons during the forelimb push was estimated to be on average 0.4 J kg(-1) in the trailing forelimb and 0.23 J kg(-1) in the leading forelimb. This means that a considerable amount of energy was first dissipated and subsequently regenerated by muscles, with triceps brachii probably being the most important contributor. During the hindlimb push, the muscles of the leg were primarily producing energy. The total increase in energy was 2.5 J kg(-1) and the peak power output amounted to 71 W kg(-1). |
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Institute for Fundamental and Clinical Human Movement Sciences, Vrije Universiteit, van der Boechorstraat 9, NL-1081 BT Amsterdam, The Netherlands. MFBobbert@fbw.vu.nl |
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0022-0949 |
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PMID:15634844 |
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1895 |
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Author |
Colahan, P.; Lindsey, E.; Nunier, C. |
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Title |
Determination of the center of pressure of the hoofs of the forelimbs of horses standing on a flat level surface |
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Journal Article |
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Year |
1993 |
Publication |
Acta Anatomica |
Abbreviated Journal |
Acta Anat (Basel) |
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146 |
Issue |
2-3 |
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175-178 |
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Animals; Forelimb/*physiology; Hoof and Claw/*physiology; Horses/*physiology; *Posture; Pressure |
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The pressure exerted on a flat level surface by recently trimmed, unshod hoofs of the front limbs of 23 sound, adult horses was measured using pressure-sensitive film and a specially built cassette. The horses were tranquilized and stood with one foot on the 2.9-cm-thick cassette and the other on a block of equal height. The hoofs were observed for motion during the measurement, and the developed film was examined for improper alignment of the film or slipping of the hoof. The center of pressure was located using the method of weighted proportions of Barrey. This static measurement system with a long measurement time and the number of measurements reduced the influence of variables inherent in the horses' behavior and the measuring system. The calculated point was recorded as falling medial to, lateral to or on a line bisecting the central sulcus of the frog. In the dorsal to palmar orientation the point was classified with reference to a line drawn halfway between the most dorsal and the most palmar mark on the film. Forty-six percent of the calculated centers of pressure were located in the medial heel area. Binomial analysis for large samples indicates that this was a significant variation from a random distribution. Seventy-six percent of the centers were located in or on the borders of the medial heel. |
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College of Veterinary Medicine, University of Florida, Gainesville 32608-0136 |
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ISSN |
0001-5180 |
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Notes |
PMID:8470462 |
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Call Number |
refbase @ user @ |
Serial |
1946 |
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Author |
Wilson, A.M.; McGuigan, M.P.; Su, A.; van Den Bogert, A.J. |
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Title |
Horses damp the spring in their step |
Type |
Journal Article |
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Year |
2001 |
Publication |
Nature |
Abbreviated Journal |
Nature |
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Volume |
414 |
Issue |
6866 |
Pages |
895-899 |
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Keywords |
Animals; Biomechanics; Elasticity; Forelimb; Gait; Horses/anatomy & histology/*physiology; Leg Bones/*physiology; Locomotion; Models, Biological; Muscle Fibers/physiology; Muscle, Skeletal/anatomy & histology/*physiology; Tendons/anatomy & histology/*physiology; Vibration |
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Abstract |
The muscular work of galloping in horses is halved by storing and returning elastic strain energy in spring-like muscle-tendon units.These make the legs act like a child's pogo stick that is tuned to stretch and recoil at 2.5 strides per second. This mechanism is optimized by unique musculoskeletal adaptations: the digital flexor muscles have extremely short fibres and significant passive properties, whereas the tendons are very long and span several joints. Length change occurs by a stretching of the spring-like digital flexor tendons rather than through energetically expensive length changes in the muscle. Despite being apparently redundant for such a mechanism, the muscle fibres in the digital flexors are well developed. Here we show that the mechanical arrangement of the elastic leg permits it to vibrate at a higher frequency of 30-40 Hz that could cause fatigue damage to tendon and bone. Furthermore, we show that the digital flexor muscles have minimal ability to contribute to or regulate significantly the 2.5-Hz cycle of movement, but are ideally arranged to damp these high-frequency oscillations in the limb. |
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Address |
Department of Veterinary Basic Sciences, The Royal Veterinary College, Hatfield, Herts AL9 7TA, UK. awilson@rvc.ac.uk |
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Language |
English |
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Series Volume |
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Edition |
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ISSN |
0028-0836 |
ISBN |
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Notes |
PMID:11780059 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2300 |
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