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Galloux, P.; Barrey, E. |
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Title  |
Components of the total kinetic moment in jumping horses |
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Journal Article |
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1997 |
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Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
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23 |
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41-44 |
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Algorithms; Animals; Exertion/*physiology; Female; Gravitation; Horses/*physiology; Kinetics; Locomotion/*physiology; Male; Models, Biological; Movement/*physiology; Video Recording |
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Thirty horses were filmed with a panning camera operating at 50 frames/s as they jumped over a 1.20 x 1.20 m fence. The markers of 9 joints on the horse and 7 joints on the rider were tracked in 2D with the TrackEye system. The centre of gravity and moment of inertia of each segment were calculated using a geometric algorithm and a cylindric model, respectively. The kinetic moment of each part of the horse was calculated after filtering, and resampling of data. This method showed the relative contribution of each body segment to the body overall rotation during the take-off, jump and landing phases. It was found that the trunk, hindlimbs and head-neck had the greatest influence. The coordination between the motion of the body segments allowed the horse to control its angular speed of rotation over the fence. This remained nearly constant during the airborne phase (120 +/- 5 degrees/s). During the airborne phase, the kinetic moment was constant because its value was equal to the moment of the external forces (722 +/- 125 kg x m2/s). |
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Ecole Nationale d'Equitation, Terrefort, Saumur, France |
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PMID:9354287 |
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Equine Behaviour @ team @ |
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3797 |
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Francis-Smith, K.; Wood-Gush, D.G.M. |
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Title |
Copropgagia as seen in thoroughbred foals |
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Journal Article |
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1977 |
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Equine veterinary journal |
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Equine Vet J |
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9 |
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3 |
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155-157 |
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animal; article; coprophagy; defecation; eating; female; horse; horse disease; human; mastication |
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Four Thoroughbred foals were seen to quickly eat part of the faeces deposited by their own dams on some 40 per cent of the mare-defaecating occasions observed between the second and fifth week after birth. They did not do it before or after this period. This behaviour was thought to be a feeding pattern which formed a normal part of the foal's development. |
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from Professor Hans Klingels Equine Reference List |
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1090 |
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Crowell-Davis, S.L.; Houpt, K.A. |
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Title |
Coprophagy by foals: effect of age and possible functions |
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Journal Article |
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1985 |
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Equine veterinary journal |
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Equine Vet J |
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17 |
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1 |
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17-19 |
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*Aging; Animals; *Coprophagia; Deoxycholic Acid/physiology; Female; Horse Diseases/*physiopathology; Horses; Humans; Male; Pheromones/physiology; Time Factors; Urination |
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In colts and fillies observed from birth to 24 weeks old, coprophagy occurred from Weeks 1 to 19. Its frequency was greatest during the first two months. Coprophagy was rarely observed in mares and stallions. Foals usually ate the faeces of their mother but were observed to eat their own and those of a stallion and another unrelated mare. Urination by the foal occurred before, during or after 26 per cent of the coprophagy incidents. It is hypothesised that foals may consume faeces in response to a maternal pheromone which signals the presence of deoxycholic acid or other acids which the foal may be deficient in and which it may require for gut immuno-competence myelination of the nervous system. Such a pheromone may also serve to accelerate growth and sexual maturation. Coprophagy may also provide nutrients and introduce normal bacterial flora to the gut. |
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0425-1644 |
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PMID:4038939 |
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refbase @ user @ |
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55 |
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Robert, C.; Valette, J.P.; Denoix, J.M. |
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Title |
Correlation between routine radiographic findings and early racing career in French trotters |
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Journal Article |
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2006 |
Publication |
Equine Veterinary Journal. Supplement |
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Equine Vet J Suppl |
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36 |
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473-478 |
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Animals; Bone and Bones/anatomy & histology/pathology/*radiography; Carpus, Animal/anatomy & histology/pathology/radiography; Horse Diseases/diagnosis/radiography; Horses/*anatomy & histology/*physiology; Physical Conditioning, Animal/*physiology; Predictive Value of Tests; Sports; Stifle/anatomy & histology/pathology/radiography; Tarsus, Animal/anatomy & histology/pathology/radiography |
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REASONS FOR PERFORMING STUDY: The relationship between the presence of radiological abnormalities and subsequent racing performance is controversial. However, as training is expensive and time consuming, it would save time and money to identify subjects with osteo-articular lesions not compatible with a normal racing career on the basis of routine radiographic screenings at yearling age. OBJECTIVES: To evaluate the impact of osteo-articular lesions on racing ability in French Trotters and identify radiographic changes associated with failure in 'qualification', in order to provide objective criteria for selection of horses based on their osteo-articular status. HYPOTHESIS: The influence of radiographic findings (RF) on racing ability depends on their nature, location, clinical relevance and number. METHODS: The limbs of 202 French Trotters were radiographed just before they started training. All the RF were graded according to a standardised protocol depending on their severity. The success in 'qualification' (first race in career of French Trotters) was the criteria used to assess racing ability. Breeders and trainers were questioned about the causes for horses not racing. RESULTS: Overall 113 (55.9%) horses qualified. Osteoarticular lesions were directly responsible for nonqualification in 31% of the horses. Subjects with more than one abnormal RF, with abnormal RF on the fore-, hind-fetlock or proximal tarsus were less likely to qualify. Dorsal modelling in the front fetlock and osteochondrosis of the lateral trochlear ridge of the femur also significantly reduced the qualification rate. CONCLUSIONS: Most RF are compatible with beginning a racing career, but severe RF or multiple abnormal RF significantly compromise future racing career. POTENTIAL RELEVANCE: This study supports the use of routine radiographic programmes for detection of osteoarticular lesions in yearlings. A synthetic radiographic score, based on both the severity and the number of lesions, could be useful for breeders and trainers as complementary information to select their horses. |
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UMR INRA-ENVA de Biomecanique et Pathologie Locomotrice du Cheval, Ecole Veterinaire d'Alfort, 7 Av. du Gal de Gaulle, 94704 Maisons-Alfort Cedex, France |
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PMID:17402469 |
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Equine Behaviour @ team @ |
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4002 |
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Gramkow, H.L.; Evans, D.L. |
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Title |
Correlation of race earnings with velocity at maximal heart rate during a field exercise test in thoroughbred racehorses |
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Journal Article |
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2006 |
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Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
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36 |
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118-122 |
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Animals; Exercise Test/veterinary; Female; Geographic Information Systems; Heart Rate/*physiology; Horses/*physiology; Linear Models; Male; Oxygen Consumption/*physiology; Physical Conditioning, Animal/*economics/*physiology; Physical Fitness/physiology; Running; Sports/economics |
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REASONS FOR PERFORMING STUDY: Running ability of Thoroughbred racehorses is correlated with maximal oxygen uptake, and the velocity at maximal oxygen uptake is highly correlated with the velocity at maximal heart rate (VHRmax). OBJECTIVE: To investigate the relationship between VHRmax and racing performance, expressed as 'peak dollars earned per race start'. METHODS: Heart rate (HR) and velocity were recorded in 25 Thoroughbred racehorses during trotting and subsequent fast gallops in the field at velocities of 15-16 m/sec. Velocity was recorded by a global positioning system (GPS). Maximal HR (HRmax) and maximal velocity (Vmax) were identified, and a linear regression of HR on velocity for trotting and galloping data was constructed to derive VHRmax. Horses followed the training programme designed by one trainer, had at least 6 race starts and were clinically sound at the time of testing. Race earnings were expressed as the peak dollars per start in the horse's race career. Data were normalised using the results for the square root of 'peak dollars earned per race start' and the significance of associations between variables was determined by correlation coefficient and least square analyses. RESULTS: Horses with higher VHRmax earned significantly more dollars per race start (r = 0.41, P<0.05), and horses with VHRmax less than 14.5 m/sec had mean earnings of less than A$2500 per race. There were no correlations between race earnings and either HRmax or Vmax. CONCLUSION: Field studies of the relationship between HR and velocity with a GPS enable identification of horses with limited earnings. POTENTIAL RELEVANCE: This study demonstrates that a field test of fitness of Thoroughbred racehorses that correlates with retrospective racing ability is feasible. The technique has potential application in commercial training environments assisting with decisions concerning racing careers of individual racehorses. |
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Faculty of Veterinary Science, University of Sydney, New South Wales 2006, Australia |
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PMID:17402405 |
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Equine Behaviour @ team @ |
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4012 |
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Albright, J.D.; Mohammed, H.O.; Heleski, C.R.; Wickens, C.L.; Houpt, K.A. |
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Crib-biting in US horses: Breed predispositions and owner perceptions of aetiology |
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Journal Article |
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2009 |
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Equine Veterinary Journal |
Abbreviated Journal |
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41 |
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5 |
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455-458 |
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Keywords |
HORSE; BEHAVIOUR; CRIB-BITING; BREED PREVALENCE; LEARNING |
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Reasons for performing study: Crib-biting is an equine stereotypy that may result in diseases such as colic. Certain breeds and management factors have been associated.
Objectives: To determine: breed prevalence of crib-biting in US horses; the likelihood that one horse learns to crib-bite from another; and owner perceptions of causal factors.
Methods: An initial postal survey queried the number and breed of crib-biting horses and if a horse began after being exposed to a horse with this habit. In a follow-up survey, a volunteer subset of owners was asked the number of affected and nonaffected horses of each breed and the extent of conspecific contact. The likelihood of crib-biting given breed and extent of contact was quantified using odds ratio (OR) and significance of the association was assessed using the Chi-squared test.
Results: Overall prevalence was 4.4%. Thoroughbreds were the breed most affected (13.3%). Approximately half of owners believed environmental factors predominantly cause the condition (54.4%) and crib-biting is learned by observation (48.8%). However, only 1.0% of horses became affected after being exposed to a crib-biter. The majority (86%) of horses was turned out in the same pasture with other horses and extent of contact with conspecifics was not statistically related to risk.
Conclusion: This is the first study to report breed prevalence for crib-biting in US horses. Thoroughbreds were the breed more likely to be affected. More owners believed either environmental conditions were a predominant cause or a combination of genetic and environmental factors contributes to the behaviour. Only a small number of horses reportedly began to crib-bite after being exposed to an affected individual, but approximately half of owners considered it to be a learned behaviour; most owners did not isolate affected horses.
Potential relevance: Genetic predisposition, not just intensive management conditions and surroundings, may be a factor in the high crib-biting prevalence in some breeds, and warrants further investigation. Little evidence exists to suggest horses learn the behaviour from other horses, and isolation may cause unnecessary stress. |
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Equine Behaviour @ team @ |
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5010 |
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Rollot, Y.; Lecuyer, E.; Chateau, H.; Crevier-Denoix, N. |
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Development of a 3D model of the equine distal forelimb and of a GRF shoe for noninvasive determination of in vivo tendon and ligament loads and strains |
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Journal Article |
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2004 |
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Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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36 |
Issue |
8 |
Pages |
677-682 |
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Animals; Biomechanics; Floors and Floorcoverings; Forelimb/*physiology/ultrasonography; Gait/physiology; Horses/*physiology; Image Processing, Computer-Assisted; Imaging, Three-Dimensional/methods/*veterinary; Ligaments, Articular/*physiology; Locomotion/*physiology; Models, Biological; Shoes; Tendons/*physiology; Toe Joint/physiology/ultrasonography |
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REASONS FOR PERFORMING STUDY: As critical locomotion events (e.g. high-speed and impacts during racing, jump landing) may contribute to tendinopathies, in vivo recording of gaits kinematic and dynamic parameters is essential for 3D reconstruction and analysis. OBJECTIVE: To propose a 3D model of the forelimb and a ground reaction force recording shoe (GRF-S) for noninvasively quantifying tendon and ligament loads and strains. METHODS: Bony segments trajectories of forelimbs placed under a power press were recorded using triads of ultrasonic kinematic markers linked to the bones. Compression cycles (from 500-6000 N) were applied for different hoof orientations. Locations of tendon and ligament insertions were recorded with regard to the triads. The GRF-S recorded GRF over the hoof wall and used four 3-axis force sensors sandwiched between a support shoe and the shoe to be tested. RESULTS: Validation of the model by comparing calculated and measured superficial digital flexor tendon strains, and evaluation of the role of proximal interphalangeal joint in straight sesamoidean ligament and oblique sesamoidean ligament strains, were successfully achieved. Objective comparisons of the 3 components of GRF over the hoof for soft and hard grounds could be recorded, where the s.d. of GRF norm was more important on hard ground at walk and trot. CONCLUSIONS: Soft grounds (sand and rubber) dissipate energy by lowering GRF amplitude and diminish bounces and vibrations at impact. At comparable speed, stance phase was longer on soft sand ground. POTENTIAL RELEVANCE: The conjugate use of the GRF-S and the numerical model would help to quantify and analyse ground/shoe combination on comfort, propulsion efficiency or lameness recovery. |
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UMR INRA-ENVA de Biomecanique et Pathologie Locomotrice du Cheval, Ecole Nationale Veterinaire d'Alfort, 7, Avenue du General de Gaulle, 94704 Maisons-Alfort, France |
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0425-1644 |
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PMID:15656495 |
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Equine Behaviour @ team @ |
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3769 |
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Drevemo, S.; Fredricson, I.; Hjertén, G.; McMIKEN, D. |
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Early development of gait asymmetries in trotting Standardbred colts |
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1987 |
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Equine Veterinary Journal |
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Equine. Vet. J. |
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19 |
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3 |
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189-191 |
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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. |
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American Medical Association (AMA) |
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https://doi.org/10.1111/j.2042-3306.1987.tb01373.x |
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Equine Behaviour @ team @ |
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6702 |
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Barrey, E.; Desliens, F.; Poirel, D.; Biau, S.; Lemaire, S.; Rivero, J.L.L.; Langlois, B. |
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Early evaluation of dressage ability in different breeds |
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Journal Article |
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2002 |
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Equine Veterinary Journal. Supplement |
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Equine Vet J Suppl |
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34 |
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319-324 |
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Animals; Biomechanics; Breeding; Discriminant Analysis; Female; Forelimb; Gait/genetics/*physiology; Hindlimb; Horses/anatomy & histology/*genetics/*physiology; Male; Photography/veterinary; *Physical Conditioning, Animal; Sports |
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Dressage is one of the Olympic equestrian sports practiced in several countries using different horse breeds. Specific characteristics of the walk, trot and canter are required for dressage. It has been assumed that some of these traits could be selected for genetically and contribute to dressage performance. The purpose of this study was to compare the walk, trot and conformation characteristics in young horses of different breeds used for dressage. A total of 142 horses age 3 years were classified into 3 groups of breeds (German, French and Spanish saddle horses) and tested using the same procedure. The skeletal conformation measurements were made by image analysis. Gait variables of the walk and trot were measured by the accelerometric gait analysis system Equimetrix. Discriminant analysis could explain the variability between the groups by taking into account the walk (P<0.0003), trot (P<0.0001) and conformation variables (P<0.0001). Many gait and conformation variables were significantly different between the breeds. In summary, the German horses had gait characteristics more adapted for dressage competition, and the results of this group could be used as a reference for early evaluation in dressage. Purebred Spanish horses could be considered as a reference for collected gaits used for farm work and old academic dressage. The gait and conformation tests could be applied in a breeding or crossing plan to detect more accurately young horses with good dressage ability. |
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INRA, Station de Genetique Quantitative et Appliquee, Groupe Cheval, Jouy-en-Josas, France |
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PMID:12405708 |
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Equine Behaviour @ team @ |
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3726 |
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Malmgren, L.; Andresen, Ø.; Dalin, A.-M. |
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Effect of GnRH immunisation on hormonal levels, sexual behaviour, semen quality and testicular morphology in mature stallions |
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2001 |
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Equine Veterinary Journal |
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Equine vet. J. |
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33 |
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1 |
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75-83 |
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horse; GnRH; immunisation; stallion; testosterone; oestrone sulphate; sexual behaviour; semen quality |
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Summary The aim of this study was to investigate the effect of gonadotrophin-releasing hormone (GnRH) immunisation on mature stallions that had been used for breeding. Four Standardbred stallions were used in the study: 3 experimental animals and 1 control animal. Semen was collected regularly, i.e. twice/week, during the 4 months prior to the experimental period. The stallions were immunised against GnRH with a GnRH-BSA conjugate. Equimune was used as the adjuvant. The stallions were immunised on 5 occasions, 4 at 2 week intervals, and the fifth 4 weeks after the fourth. Blood samples were taken once a week for analysis of GnRH antibody titre and every third week for testosterone and oestrone sulphate analyses. Semen was collected once a week, and libido and sexual behaviour were observed. Ejaculate volume, sperm concentration, total number of sperm in the ejaculate, sperm motility and sperm morphology were evaluated. Testicular size was measured once a week. At the end of the study, the stallions were castrated, and a histological examination of the testes performed. All immunised stallions produced antibodies against GnRH, and plasma testosterone concentration decreased. However, the effect of immunisation varied between stallions. In 2 of the stallions, high levels of antibodies were found, while in the third, the level was moderate. Four weeks after the first immunisation, a decrease in libido was observed. Two months after the first immunisation, marked changes in semen quality were observed in the 2 stallions with high antibody titres. Fourteen weeks after the first immunisation, the total number of sperm/ejaculate had decreased from >8.6×109 to<2.7×109, sperm motility from >59 to<10% and the frequency of morphological normal spermatozoa had decreased from >60 to<14%. The dominating abnormalities were abnormal head shapes, proximal cytoplasmic droplets and detached heads. In the third stallion, only slight changes in semen quality were found. No changes were observed in the control stallion. Decreases in testicular size were noted in all of the experimental stallions. Pronounced histological alterations in the testes were observed in 2 of the stallions. It is concluded that the vaccine was effective in stimulating production of GnRH antibodies and in suppressing testicular function and androgen secretion. However, there was an individual variation in the responses among the stallions and, further, libido was not totally suppressed. |
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Blackwell Publishing Ltd |
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2042-3306 |
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Equine Behaviour @ team @ |
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5312 |
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