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1.
  • Andersson, Lisa, et al. (författare)
  • Mutations in DMRT3 affect locomotion in horses and spinal circuit function in mice
  • 2012
  • Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 488:7413, s. 642-646
  • Tidskriftsartikel (refereegranskat)abstract
    • Locomotion in mammals relies on a central pattern-generating circuitry of spinal interneurons established during development that coordinates limb movement(1). These networks produce left-right alternation of limbs as well as coordinated activation of flexor and extensor muscles(2). Here we show that a premature stop codon in the DMRT3 gene has a major effect on the pattern of locomotion in horses. The mutation is permissive for the ability to perform alternate gaits and has a favourable effect on harness racing performance. Examination of wild-type and Dmrt3-null mice demonstrates that Dmrt3 is expressed in the dI6 subdivision of spinal cord neurons, takes part in neuronal specification within this subdivision, and is critical for the normal development of a coordinated locomotor network controlling limb movements. Our discovery positions Dmrt3 in a pivotal role for configuring the spinal circuits controlling stride in vertebrates. The DMRT3 mutation has had a major effect on the diversification of the domestic horse, as the altered gait characteristics of a number of breeds apparently require this mutation.
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  • Bergström, Annika, et al. (författare)
  • Long-Term Effect of Intra-Articular Adipose-Derived Stromal Vascular Fraction and Platelet-Rich Plasma in Dogs with Elbow Joint Disease-A Pilot Study
  • 2024
  • Ingår i: Veterinary Sciences. - 2306-7381. ; 11
  • Tidskriftsartikel (refereegranskat)abstract
    • Elbow osteoarthritis (OA) is a common cause of pain and lameness in dogs, often resulting from the developmental disorder elbow dysplasia. Currently, there is no effective treatment or cure for this disease. This study aimed to evaluate the effect of treating dogs with OA with stem cells (SVF, stromal vascular fraction) and blood plasma rich in platelets (PRP) derived from the dog's own fat and blood, respectively. The mixture was administered as a single injection into affected elbows. Nineteen dogs with elbow OA were treated with SVF and PRP. Subjective and objective evaluations were performed before treatment, after six months, and after a minimum of one year. A "Symmetry Squares" graphic presentation of objective gait forces (peak force and impulse) was also used to compare changes in gait over time. The results showed that subjective evaluation of clinical lameness was improved at the six-month follow up evaluation and that the peak force was transferred from the hind limbs to the front limbs in the treated dogs after 12 months. However, the treatment failed to show a general evident effect. Further research should be conducted to evaluate whether SVF and PRP treatment should be recommended for dogs with elbow OA. (1) Background: The aim of the current pilot study was to describe the long-term effects of a single intra-articular injection of autologous stromal vascular fraction (SVF) with platelet-rich plasma (PRP) in dogs with confirmed elbow OA, using orthopedic lameness scoring and kinetic and kinematic gait analysis. For comparison of normal long-term variation of gait over time, a group of healthy control dogs (CDs) was also evaluated. (2) Methods: A prospective longitudinal clinical pilot study investigating 19 client-owned dogs with elbow OA (OADs) treated with SVF and PRP and eight CDs not receiving treatment. The OAD and CD groups were evaluated before and after 6 and at least 12 months following treatment with SVF and PRP (OAD group) and twice with a six-month interval (CD group), respectively, through orthopedic examinations, goniometry, and kinetic and kinematic analyses (seven variables). (3) Results: The OAD had an increase in fore-hind peak force symmetry >= 12 months after treatment (p < 0.05), but no other objective variables changed over time. Orthopedic consensus scores had improved at >= six months follow-up evaluation (p < 0.05). None of the investigated gait variables had changed at >= six months follow-up evaluation in the CD group. (4) Conclusions: The current study could not confirm a significant benefit from SVF and PRP treatment in OADs, but future studies should be conducted in order to fully evaluate the potential of the treatment. The improvement seen in fore-hindlimb symmetry may represent an improvement in gait or an incidental finding.
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4.
  • Braam, Åsa, et al. (författare)
  • Genetic variation in durability of Swedish Warmblood horses using competition results
  • 2011
  • Ingår i: Livestock Science. - : Elsevier BV. - 1871-1413 .- 1878-0490. ; 142, s. 181-187
  • Tidskriftsartikel (refereegranskat)abstract
    • The aim of the study was to investigate the possibilities of using number of years in competition as a measure of durability in the genetic evaluation of Swedish Warmblood horses. Competition results recorded between 1971 and 2008 in the disciplines dressage, show jumping and eventing were used to estimate genetic parameters for number of years in competition. Only male horses not used in breeding born between 1967 and 1991 were included in the study (17,962 horses). The study showed that horses with placings in more than one discipline at an early age had the longest competition career. This result suggests that these horses are talented for sports and possibly also that there is a positive effect of all-round training of young horses on their durability. For estimation of genetic parameters for number of years in competition different linear mixed animal models were compared. Depending on the model and transformation the heritability for total number of years in competition varied between 0.07 and 0.17. The lower values were obtained when adjustments in the model were made for age at first placing in competition. Higher heritabilities were obtained for competition years in show jumping and lower for eventing. Performance traits scored at young horse tests and as points in competition (lifetime and for young horses) showed positive genetic correlations with total number of years in competition. These results indicate that years in competition represent both the durability of the horses and their talents for performance. It is suggested that number of years in competition may be used for genetic evaluation of durability.
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  • Byström, Anna, et al. (författare)
  • Asymmetries of horses walking and trotting on treadmill with and without rider
  • 2020
  • Ingår i: Equine Veterinary Journal. - : Wiley. - 0425-1644 .- 2042-3306. ; 53, s. 157-166
  • Tidskriftsartikel (refereegranskat)abstract
    • 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.
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  • Byström, Anna, et al. (författare)
  • Biomechanical findings in horses showing asymmetrical vertical excursions of the withers at walk
  • 2018
  • Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 13
  • Tidskriftsartikel (refereegranskat)abstract
    • 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.
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9.
  • Byström, Anna, et al. (författare)
  • Differences in equine spinal kinematics between straight line and circle in trot
  • 2021
  • Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 11
  • Tidskriftsartikel (refereegranskat)abstract
    • Work on curved tracks, e.g. on circles, is commonplace within all forms of horse training. Horse movements in circles are naturally asymmetric, including the load distribution between inner and outer limbs. Within equestrian dressage the horse is expected to bend the back laterally to follow the circle, but this has never been studied scientifically. In the current study 12 horses were measured (optical motion capture, 100 Hz) trotting on left and right circles and on the straight without rider (soft surface). Data from markers placed along the spine indicated increased lateral bending to the inside (e.g. left bending on the left circle) of the thoracolumbar back (difference left circle vs. straight - 3.75 degrees; right circle+3.61 degrees) and the neck (left - 5.23 degrees; right+4.80 degrees vs. straight). Lateral bending ROM increased on the circle (+0.87 degrees and+0.62 degrees). Individual variation in straight-circle differences was evident, but each horse was generally consistent over multiple trials. Differences in back movements between circle and straight were generally small and may or may not be visible, but accompanying changes in muscle activity and limb movements may add to the visual impression.
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10.
  • Byström, Anna, et al. (författare)
  • Differences in rider movement pattern between different degrees of collection at the trot in high-level dressage horses ridden on a treadmill
  • 2015
  • Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457 .- 1872-7646. ; 41, s. 1-8
  • Tidskriftsartikel (refereegranskat)abstract
    • Collection is a central term in equine dressage, defined as a shortening of the horse's stride length with retained energy and hind limb activity. How collection is induced by the rider has yet not been investigated objectively. The aim of this study was therefore to compare the movement pattern of high-level dressage riders between free trot (loose reins), passage and a range of three speeds in collected trot.Both at higher speed in collected trot and in passage, the rider's pelvis became more caudally rotated and the rider's lumbar back became more flexed. However, in passage there was also a decrease in phase-shift between horse and rider movements, suggesting that the rider used the seat more actively. In free trot, the rider's pelvis was more cranially rotated, the lumbar back was more extended, the rider's body inclined more forwards, and the phase-shift between horse and rider was increased, compared to collected trot. The observed changes were partly explainable from changes in the horse's movement pattern. However, most differences in rider body position seemed unrelated to the horse's movements, but were in accordance with instructions in equestrian texts, suggesting that those changes were voluntarily adopted by the riders. (C) 2015 Elsevier B.V. All rights reserved.
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  • Byström, Anna, et al. (författare)
  • Influence of girth strap placement and panel flocking material on the saddle pressure pattern during riding of horses
  • 2010
  • Ingår i: Equine Veterinary Journal. - : Wiley. - 0425-1644 .- 2042-3306. ; 42, s. 502-509
  • Tidskriftsartikel (refereegranskat)abstract
    • Both flocking material and girthing have a significant influence on the saddle pressure and should thus be considered in saddle fitting. Wool seems a better flocking material than foam of the type used in the current study. For girthing, traditional placement seems equally good if not better than the v-system. However, further studies are needed to show if these results are valid for a larger population of riding horses.
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13.
  • Byström, Anna, et al. (författare)
  • Kinematics of saddle and rider in high-level dressage horses performing collected walk on a treadmill
  • 2010
  • Ingår i: Equine Veterinary Journal. - : Wiley. - 0425-1644 .- 2042-3306. ; 42, s. 340-345
  • Tidskriftsartikel (refereegranskat)abstract
    • The literature suggests that the rider's influence on the movement pattern of the horse is the strongest at walk. For assessment of the horse-rider interaction in dressage horses presented for unsatisfactory performance, evaluations at walk may therefore be the most rewarding. Basic knowledge about rider and saddle movements in well-performing horses is likely to be supportive to this task.
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  • Byström, Anna, et al. (författare)
  • Kinetics and kinematics of the passage
  • 2009
  • Ingår i: Equine Veterinary Journal. - 0425-1644 .- 2042-3306. ; 41, s. 263-267
  • Konferensbidrag (refereegranskat)abstract
    • Potential clinical relevance: An understanding of load distribution between fore- and hindlimbs in relation to different riding techniques is crucial to prevent wear-and-tear on the locomotor apparatus.
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15.
  • Byström, Anna, et al. (författare)
  • Lateral movement of the saddle relative to the equine spine in rising and sitting trot on a treadmill
  • 2018
  • Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 13
  • Tidskriftsartikel (refereegranskat)abstract
    • Saddle slip, defined as a progressive lateral displacement of the saddle during ridden exercise, has recently been given attention in the scientific press as a potential sign of lameness. The aim of this study was to objectively quantify the normal lateral movement (oscillations) of the saddle relative to the horse in non-lame horses, and associate this movement to the movements of the horse and rider. Data from seven Warmblood dressage horses competing at Grand Prix (n = 6) or FEI Intermediate (n = 1) level, ridden by their usual riders, were used. Simultaneous kinetic, kinematic and saddle pressure measurements were conducted during sitting and rising trot on a force-measuring treadmill. The maximum lateral movement of the caudal part of the saddle relative to the horse's spine (MAX) was determined for each diagonal step. A mixed model was applied, with MAX as outcome, and T6 and S3 vertical position, rigid body rotation angles (roll, pitch, yaw) of the horse's and rider's pelvis, vertical ground reaction forces, saddle force, and rider position (rising in rising trot, sitting in rising trot or sitting in sitting trot) as explanatory variables. The least square means for MAX were 14.3 (SE 4.7) mm and 23.9 (SE 4.7) mm for rising and sitting in rising trot, and 20.3 (SE 4.7) mm for sitting trot. A 10 mm increase in maximum pelvic height at push off increased MAX by 1.4 mm (p<0.0001). One degree increase in rider pelvis roll decreased MAX 1.1 mm, and one degree increase in rider pelvis yaw increased MAX 0.7 mm (both p<0.0001). The linear relationships found between MAX and movements of both horse and rider implies that both horse and rider movement asymmetries are reflected in the lateral movements or oscillations of the saddle in non-lame horses.
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  • Byström, Anna, et al. (författare)
  • Range of motion and between-measurement variation of spinal kinematics in sound horses at trot on the straight line and on the lunge
  • 2020
  • Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 15
  • Tidskriftsartikel (refereegranskat)abstract
    • Clinical assessment of spinal motion in horses is part of many routine clinical exams but remains highly subjective. A prerequisite for the quantification of spinal motion is the assessment of the expected normal range of motion and variability of back kinematics. The aim of this study was to objectively quantify spinal kinematics and between-measurement,-surface and-day variation in owner-sound horses. In an observational study, twelve ownersound horses were trotted 12 times on four different paths (hard/soft straight line, soft lunge left and right). Measurements were divided over three days, with five repetitions on day one and two, and two repetitions on day three (recheck) which occurred 28-55 days later. Optical motion capture was used to collect kinematic data. Elements of the outcome were: 1) Ranges of Motion (ROM) with confidence intervals per path and surface, 2) a variability model to calculate between-measurement variation and test the effect of time, surface and path, 3) intraclass correlation coefficients (ICC) to determine repeatability. ROM was lowest on the hard straight line. Cervical lateral bending was doubled on the left compared to the right lunge. Mean variation for the flexion-extension and lateral bending of the whole back were 0.8 and 1 degrees. Pelvic motion showed a variation of 1.0 (pitch), 0.7 (yaw) and 1.3 (roll) degrees. For these five parameters, a tendency for more variation on the hard surface and reduced variation with increased repetitions was observed. More variation was seen on the recheck (p<0.001). ICC values for pelvic rotations were between 0.76 and 0.93, for the whole back flexion-extension and lateral bending between 0.51 and 0.91. Between-horse variation was substantially higher than within-horse variation. In conclusion, ROM and variation in spinal biomechanics are horse-specific and small, necessitating individual analysis and making subjective and objective clinical assessment of spinal kinematics challenging.
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  • Egenvall, Agneta, et al. (författare)
  • Analysis of morbidity and mortality data in riding school horses, with special regard to locomotor problems
  • 2009
  • Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 88, s. 193-204
  • Tidskriftsartikel (refereegranskat)abstract
    • The incidence of disease, mortality and survival of horses, focusing on locomotor problems, at riding schools were studied, using data from an animal insurance database during 1997-2002. In total 5140 horses from 136 riding schools were included in the analysis. The overall yearly incidence rate (111) was 1584 events of veterinary care per 10,000 horse-years at risk (HYAR). The total and diagnostic mortalities were 790 and 763 deaths per 10,000 HYAR. Rates varied substantially among riding schools. For locomotor problems the rates were 1116 events of veterinary care and 524 deaths per 10,000 HYAR. Multivariable Cox proportional-hazards analysis was performed on horses enrolled in insurance during the study period, including riding schools as frailty effects. For the outcome veterinary care for locomotor problems, the hazard ratios (HR) increased with increasing life-insurance value and Swedish warmbloods and other horses had increased HR compared to ponies. In the model with outcome life claim because of locomotor problems the breed groups Swedish warmblood and other horses also had higher HR than ponies. Age at entry >= 8 years was associated with decreased HR for settled life-insurance cases due to locomotor problems and the two highest categories for insurance value had increased HR compared to the two lower categories. In the model with the outcome life claim because of previously claimed locomotor problems Swedish warmbloods had a higher HR than other horses and ponies. The HR increased by 33% for each year of age at entry. In south-urban areas of Sweden the HR was decreased compared to in all other areas, including baseline. Overall riding schools utilised the insurance more compared to all horses in the insurance database (similar to 22% for the veterinary-care insurance and similar to 79% for the settled life insurance). (C) 2008 Elsevier B.V. All rights reserved.
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19.
  • Egenvall, Agneta, et al. (författare)
  • Days-lost to training and competition in relation to workload in 263 elite show-jumping horses in four European countries
  • 2013
  • Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 112, s. 387-400
  • Tidskriftsartikel (refereegranskat)abstract
    • Orthopaedic, or other, injuries in sports medicine can be quantified using the ‘days-lost to training’ concept. Both the training regimen and the surface used in training and racing can affect the health of racehorses. Our aim was to associate ‘days-lost to training’ in elite-level show-jumpers to horse characteristics, training and management strategies, and the time spent working on various training and competition surfaces. We designed a longitudinal study of professional riders in four European countries. Data were recorded using training diaries. Reasons for days-lost were classified into non-acute and acute orthopaedic, medical, hoof-related, and undefined. We produced descriptive statistics of training durations, relative to type of training, surfaces used, and days-lost. We created zero-inflated negative-binomial random-effects models using the overall days-lost as outcome. In the whole dataset, duration variables related to training surfaces were analysed as independent. The Swedish data only were also used to test whether duration variables were related to competition surfaces. Thirty-one riders with 263 horses provided data on 39,028 days at risk. Of these, 2357 (6.0%) were days-lost (55% and 22% of these were due to non-acute and acute orthopaedic injuries, respectively) in 126 horses. In the all-country model, controlling for season, a significant variable was country. Switzerland and the UK had lower incidence-rate ratios (IR) compared to Sweden (IRs 0.2 and 0.03, respectively). Horses with previous orthopaedic problems had almost a doubled IR (1.8) of days-lost due to orthopaedic injury, compared to baseline. If the horse had jumping training more than 1 minute per day at risk the IRs were 6.9-7 (compared to less than this amount of time); this was, however, likely an effect of a small baseline. Variation in training was a protective factor with a dose-response relationship; the category with the highest variation had an IR of 0.1. In the Swedish model, controlling for season, there was an association of year (IR 2.8 year 2010). Further, if the horse rested >17-25% of the days at risk, or >33% of the DAR2, had IRs 3.5 and 3,0, compared to less time. Horses ≥6 years had IRs of 1.8-2.0, compared to younger horses. Limited training use of sand surface was a risk-factor (IR 2.2; >4≤12 min/day at risk), compared to not training on sand. Training/competing on sand-wood was a protective factor (IRs 0.4-0.5) compared to not using this surface.
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20.
  • Egenvall, Agneta, et al. (författare)
  • Horse-rider interaction
  • 2013
  • Ingår i: Equine Locomotion. - 9780702029509 ; , s. 341-368
  • Bokkapitel (övrigt vetenskapligt/konstnärligt)
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22.
  • Egenvall, Agneta, et al. (författare)
  • Integrating databases for research on health and performance in small animals and horses in the Nordic countries
  • 2011
  • Ingår i: Acta Veterinaria Scandinavica. - 0044-605X .- 1751-0147. ; 53, s. 1-6
  • Tidskriftsartikel (refereegranskat)abstract
    • Nordic examples of the use of secondary small animal and equine databases include studies based on data from tumour registries, breeding registries, young horse quality contest results, competition data, insurance databases, clinic data, prescription data and hunting ability tests. In spite of this extensive use of secondary databases, integration between databases is less common. The aim of this presentation is to briefly review key papers that exemplify different ways of utilizing data from multiple sources, to highlight the benefits and limitations of the approaches, to discuss key issues/challenges that must be addressed when integrating data and to suggest future directions. Data from pedigree databases have been individually merged with competition data and young horse quality contest data, and true integration has also been done with canine insurance data and with equine clinical data. Data have also been merged on postal code level; i.e. insurance data were merged to a digitized map of Sweden and additional meteorological information added. In addition to all the data quality and validity issues inherent in the use of a single database, additional obstacles arise when combining information from several databases. Loss of individuals due to incorrect or mismatched identifying information can be considerable. If there are any possible biases affecting whether or not individuals can be properly linked, misinformation may result in a further reduction in power. Issues of confidentiality may be more difficult to address across multiple databases. For example, human identity information must be protected, but may be required to ensure valid merging of data. There is a great potential to better address complex issues of health and disease in companion animals and horses by integrating information across existing databases. The challenges outlined in this article should not preclude the ongoing pursuit of this approach.
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23.
  • Egenvall, Agneta, et al. (författare)
  • Maximum and minimum peaks in rein tension within canter strides
  • 2016
  • Ingår i: Journal of Veterinary Behavior: Clinical Applications and Research. - : Elsevier BV. - 1558-7878 .- 1878-7517. ; 13, s. 63-71
  • Tidskriftsartikel (refereegranskat)abstract
    • Equestrians use reins to communicate with the horse. The aim of this study was to describe the amplitudes of rein tension oscillations at canter. Rein tension data were collected from 8 professional riders each riding 2-3 horses during a normal dressage training session using rein tension meters (128 Hz, logged by an inertial measurement unit sensor). Data were stride-split at the maximal positive vertical poll acceleration. Strides were categorized by canter lead, rider position (sitting/2 point), corners, circles, lateral movements, and stride length (collected/working/lengthened). Changes in head angle were determined from gyroscopic sensor data. Dependent data extracted from each stride and rein were maximal tension (MAX), minimal tension (MIN), and the absolute difference between them (CHANGE). Square-root transformed data were analyzed using mixed models with stride categorizations as fixed effects, and rider and horse included as random effects. Findings for rein tension were considered borderline if 0.050.001, but significant if P < 0.001. For the rider's position, the magnitudes were higher in sitting canter than 2-point seat (P < 0.0001), except for inside rein MIN value (n = 21,548 strides). For MAX (both reins), MIN (inside), and CHANGE (outside), the right circle had lower values than the left circle or no circle. For the outside rein, MAX and MIN values showed borderline differences with higher values for lengthened strides than working canter (P = 0.03/0.0014). Inside rein values in right half pass were significantly or borderline higher than left half pass or baseline, and for MIN values, this was found for both inside/outside reins. Both group effects and all pairwise comparisons evaluated were significant for MAX and CHANGE, except the comparison between inside and outside rein in right canter. MAX/MIN tensions were higher if the nose was moving caudally relative to poll at the MAX/MIN event, respectively. Young horses had the largest MAX and CHANGE values, whereas advanced horses had the highest MIN values. The horse contributed 7%, 27%, and 29% of the variation to MIN, MAX, and CHANGE models, respectively. The rider contributed 19% of the variation to the MIN value models but 0% to the MAX and CHANGE models, suggesting that the horse or the dyad (not statistically separable) is responsible for the basic rein tension pattern at canter. Overall results indicate that asymmetry, of riders and/or horses, plays a role in rein tension. (c) 2016 Elsevier Inc. All rights reserved.
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24.
  • Egenvall, Agneta, et al. (författare)
  • Modelling rein tension during riding sessions using the generalised additive modelling technique
  • 2018
  • Ingår i: Comparative Exercise Physiology. - 1755-2540 .- 1755-2559. ; 14, s. 209-221
  • Tidskriftsartikel (refereegranskat)abstract
    • General additive modelling (GAM-modelling) is an exploratory technique that can be used on longitudinal (time series) data, e.g. rein tension, over a period of time. The aim was to apply GAM-modelling to investigate changes in rein tension during a normal flatwork training session. Six riders each rode two or three of their horses (n=17 horses) during a normal flatwork/dressage training session with video recordings and rein tension measurements (128 Hz). Training sessions were classified according to rider position, stride length and whether horses were straight, bent to the left or bent to the right. The rein tension data were split into strides and for each stride minimal (MIN) and maximal (MAX) rein tension were determined and the area under the rein tension curve (AUC) was calculated. Using data on a contact the three outcome variables MIN, MAX and AUC rein tension were modelled by horse and rein (left/right), and time within the session was modelled as a smooth function. Two additional sets of models were constructed; one set using data within-rein with gait as a fixed effect and one set with rein and gait as fixed effects. Mean ± standard deviation values were MIN: 8.0±7.7 N, AUC: 180±109 Ns, and MAX: 49±31 N. GAM-modelling extracted visually interpretable information from the originally chaotic rein tension signals. Modelled data suggest that MIN, AUC and MAX follow the same pattern within horse. In general, rein tension was lowest in walk, intermediate in trot and highest in canter. Evaluating the entire ride, 12/17 horses systematically showed higher tension in the right rein. It is concluded that GAM-models may be useful for detecting patterns through time in biomechanical data.
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25.
  • Egenvall, Agneta, et al. (författare)
  • Movement asymmetries in horses presented for prepurchase or lameness examination
  • 2022
  • Ingår i: Equine Veterinary Journal. - : Wiley. - 0425-1644 .- 2042-3306. ; 54, s. 334-346
  • Tidskriftsartikel (refereegranskat)abstract
    • Background The increasing popularity of objective gait analysis makes application in prepurchase examinations (PPE) a logical next step. Therefore, there is a need to have more understanding of asymmetry during a PPE in horses described on clinical evaluation as subtly lame.Objectives The objective of this study is to objectively compare asymmetry in horses raising minor vet concerns in a PPE and in horses raising major vet concerns with that found in horses presented with subtle single-limb lameness, and to investigate the effect of age/discipline on the clinicians' interpretation of asymmetry on the classification of minor vet concerns in a PPE.Study Design Clinical case-series.Methods Horses presented for PPE (n = 98) or subjectively evaluated as single limb low-grade (1-2/5) lame (n = 24, 13 forelimb lame, 11 hindlimb lame), from the patient population of a single clinic, were enrolled in the study provided that owners were willing to participate. Horses undergoing PPE were assigned a classification of having minor vet concerns (n = 84) or major vet concerns (n = 14) based on findings during the dynamic-orthopaedic part of the PPE. Lame horses were only included if pain-related lameness was confirmed by an objective improvement after diagnostic analgesia exceeding daily variation determined for equine symmetry parameters using optical motion capture. Clinical evaluation was performed by six different clinicians, each with >= 8 years of equine orthopaedic experience. Vertical movement symmetry was measured using optical motion capture, simultaneously with the orthopaedic examination. Data were analysed using previously described parameters and mixed model analysis and least squares means were used to calculate differences between groups.Results There was no effect of age or discipline on the levels of asymmetry within PPE horses raising minor vet concerns. MinDiff and RUD of the head discriminated between forelimb lame and PPE horses raising minor vet concerns; MinDiff, MaxDiff, RUD of the Pelvis, HHDswing and HHDstance did so for hindlimb lameness. Two lameness patterns differentiated both forelimb and hindlimb lame from PPE horses with minor vet concerns: RUD Poll + MinDiff Withers - RUD Pelvis and RUD Pelvis + RUD Poll - MinDiff Withers. Correcting for vertical range of motion enabled differentiation of PPE horses with minor vet concerns from PPE horses with major vet concerns.Main Limitations Objective data only based on trot on soft surface, limited number of PPE horses with major vet concerns.Conclusions Combinations of kinematic parameters discriminate between PPE horses with minor vet concerns and subtly lame horses, though overlap exists.
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26.
  • Egenvall, Agneta, et al. (författare)
  • Orthopaedic health status of horses from 8 riding schools - a pilot study
  • 2010
  • Ingår i: Acta Veterinaria Scandinavica. - : Springer Science and Business Media LLC. - 0044-605X .- 1751-0147. ; 52
  • Tidskriftsartikel (refereegranskat)abstract
    • Conclusion: The age distribution differed markedly between riding schools and age affected several types of findings. This, combined with the two opposite groups of insurance use, shows that schools with low insurance utilisation had previously been able to "avoid" using the insurance, maybe even on similar types of cases if these were more promptly/differently handled indicating differential coverage of disease data in the insurance database. The examiner effect was clearly demonstrated. For some findings, the amount of clinical observations differed by school, even when examiner and age was adjusted for. Most findings were of minor importance, including slight movement irregularities. Orthopaedic status varies between riding schools. We hypothesize that this is associated with management factors that warrant further study.
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27.
  • Egenvall, Agneta, et al. (författare)
  • Pilot study of behavior responses in young riding horses using 2 methods of making transitions from trot to walk
  • 2012
  • Ingår i: Journal of Veterinary Behavior: Clinical Applications and Research. - : Elsevier BV. - 1558-7878 .- 1878-7517. ; 7, s. 157-168
  • Tidskriftsartikel (refereegranskat)abstract
    • According to the principles of negative reinforcement, when an aid has been given to an animal, it should be released as soon as the desired response has been achieved, and, if performed well, may be associated with fewer conflict behaviors than otherwise. In riding, pressure in the horse's mouth from the bit is used to give signals to the horse, and both rein tension and patterns of releasing this tension will vary. The aim of this pilot study was to study horse behavior during 2 different methodologies used to shape relatively naive horses to a deceleration signal while making downward transitions from trot to walk. Method I involved relief from rein tension at the first attempt to perform a correct response (M1), and method 2 entailed that rein tension was relieved at the completed correct response (M2). Four horses were ridden by 4 riders over 4 days (I rider each day), and each horse made 10 transitions each day for each method, which produced 320 transitions. Rein tension was recorded, and horse behavior and rider signal behaviors were evaluated from video recordings. Horse behavior was divided into the following 3 different categories: "pushing against the bit," "moving away from the bit," and "decelerating." Linear models were constructed tracking the percent of the transition time that horses demonstrated at least 1 behavior in the "pushing against the bit," "moving away from the bit," and "decelerating" categories, and with random effects for rider, horse, and transition number nested within horse. Fixed effects analyzed were the methods, proportion of the transition time above 30 N for each rein, and the rider signal behaviors. M1 and M2 had on average 19% (standard deviation: 16) and 38% (standard deviation: 23) of the time with >30 N per rein, respectively. In the models for the "pushing against the bit" behaviors, M2 increased rein tension and "exerting pressure on the reins" increased the level of these behaviors. "Releasing pressure" interacted with "pulling back on the reins"; this combination was associated with an increased level of "pushing against the bit" behaviors. The "decelerating" behavior was associated with lower rein tension. In the "decelerating" behavior models, "pulling back on the reins" led to decreased "decelerating" behavior, whereas "still hand" and "releasing pressure" led to increased "decelerating" behavior; however, the interaction "pulling back on the reins" and "releasing pressure" led to decreased "decelerating" behavior. "Moving away from the bit" had no significant determinants. We concluded that fewer "pushing against the bit" behaviors were created by M1 and that a lower rein tension was associated with the "decelerating" behavior. Reinforcing the horse's attempts, to assist in finding the correct response, benefits the welfare of the horse, and importance of a light hand should be continuously emphasized during riding education. (C) 2012 Elsevier Inc. All rights reserved.
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28.
  • Egenvall, Agneta, et al. (författare)
  • Rein tension during canter
  • 2015
  • Ingår i: Comparative Exercise Physiology. - 1755-2540 .- 1755-2559. ; 11, s. 107-117
  • Tidskriftsartikel (refereegranskat)abstract
    • Riders generally use reins as a means for communication with the horse. At present, the signalling pattern is poorly understood. The aim of this study was to illustrate and analyse the rein tension patterns in a number of rider/horse combinations across a variety of exercises in the canter gait. Our hypothesis was that some riders will follow the movement of the horse more closely than others. Data were collected from eight professional riders riding each three (in one case two) horses that were familiar to them in canter. Horses were instrumented with rein tension meters logged by inertial measurement unit technique (IMU). Inside and outside rein tension data were synchronised with the gait using the vertical acceleration IMU-signal at the poll. Stride-split data (0-100 percentages) were analysed using mixed models technique to elucidate the inside/outside and stride percentage interaction, taking into account the exercises performed. In general, tension was maximal just before the beginning of vertical stance, as defined by the maximal acceleration of the head, with the release closer to the suspension phase. The release was significantly more marked on the outside rein, but between riders and horses the pattern varied substantially. In total 26% of the variation was represented by riders and 21% by the horses. On average there were significant inside/outside rein differences, but at the same time in some horse/rider combinations these differences did not exist.
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29.
  • Egenvall, Agneta, et al. (författare)
  • Rein Tension During Transitions
  • 2016
  • Ingår i: Equine Veterinary Journal. - : Wiley. - 0425-1644 .- 2042-3306. ; 48, s. 26-26
  • Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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30.
  • Egenvall, Agneta, et al. (författare)
  • Rein Tension in Transitions and Halts during Equestrian Dressage Training
  • 2019
  • Ingår i: Animals. - : MDPI AG. - 2076-2615. ; 9
  • Tidskriftsartikel (refereegranskat)abstract
    • Simple Summary In the equestrian dressage discipline, the transitions (changes) between gaits and into halts, occur often in riding sessions. Rein tension before, during and after the transitions between gaits, and the transitions into halts were studied. The vertical motion data for the horse's head and croup, and rein tension data were collected from six professional riders, each riding three of their own horses during normal training sessions. The horse training levels varied from basic to advanced. The activities during the sessions were categorised into gaits, transitions between gaits and into halts based on video evaluation. The transitions were categorised according to whether they had intermediate steps that were not characteristic of the preceding or the following gait. The rein tension just before the transition was strongly related to rein tension during the transitions. There was slightly lower tension during the upward transitions than during the downward transitions. There was no difference in rein tension depending on whether intermediate steps were present or not. The left rein tension was generally lower than the right rein tension. The rein tension associated with the transitions and halts varied substantially between riders and also the horses. This information is useful for trainers seeking to understand the rein tension patterns associated with transitions.Abstract In dressage, the performance of transitions between gaits and halts is an integral part of riding sessions. The study aimed to evaluate rein tension before, during and after the transitions between different gaits and the transitions into halts. The kinematic (inertial measurement units) data for the head and croup, and rein tension data, were collected (128 Hz) from six professional riders each riding three of their own horses, training levels varying from basic to advanced, during normal training sessions. The activities were categorised into gaits, halts and transitions based on video evaluation. The transitions were categorised as without (type 1) or with (type 2) intermediate steps that are not normally present in the gaits preceding or following the transition. The differences in the median rein tension before/during/after transitions, between the types and left/right reins were analysed in mixed models. The rein tension just before the transition was the strongest determinant of tension during the transition. The rein tension was slightly lower during upward transitions compared to downward transitions, reflecting the pattern of the preceding gait. Type 1 and 2 downward transitions were not different regarding rein tension. The left rein tension was lower than right rein tension. The rein tension associated with the transitions and halts varied substantially between riders and horses. The generally strong association of the gaits and their inherent biomechanics with rein tension should be taken into account when riding transitions and halts.
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31.
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32.
  • Egenvall, Agneta, et al. (författare)
  • Stride-related rein tension patterns in walk and trot in the ridden horse
  • 2015
  • Ingår i: Acta Veterinaria Scandinavica. - : Springer Science and Business Media LLC. - 0044-605X .- 1751-0147. ; 57
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The use of tack (equipment such as saddles and reins) and especially of bits because of rein tension resulting in pressure in the mouth is questioned because of welfare concerns. We hypothesised that rein tension patterns in walk and trot reflect general gait kinematics, but are also determined by individual horse and rider effects. Six professional riders rode three familiar horses in walk and trot. Horses were equipped with rein tension meters logged by inertial measurement unit technique. Left and right rein tension data were synchronized with the gait.Results: Stride split data (0-100 %) were analysed using mixed models technique to elucidate the left/right rein and stride percentage interaction, in relation to the exercises performed. In walk, rein tension was highest at hindlimb stance. Rein tension was highest in the suspension phase at trot, and lowest during the stance phase. In rising trot there was a significant difference between the two midstance phases, but not in sitting trot. When turning in trot there was a significant statistical association with the gait pattern with the tension being highest in the inside rein when the horse was on the outer fore-inner hindlimb diagonal.Conclusions: Substantial between-rider variation was demonstrated in walk and trot and between-horse variation in walk. Biphasic rein tensions patterns during the stride were found mainly in trot.
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33.
  • Egenvall, Agneta, et al. (författare)
  • The Descriptions and Attitudes of Riders and Arena Owners to 656 Equestrian Sport Surfaces in Sweden
  • 2021
  • Ingår i: Frontiers in Veterinary Science. - : Frontiers Media SA. - 2297-1769. ; 8
  • Tidskriftsartikel (refereegranskat)abstract
    • Horses in equestrian sports are commonly trained in arenas with prepared footing. Information on the number and variants of such arenas is generally unknown. This paper provides an overview of the primary construction types of riding surfaces in Sweden including details on composition, constructions principles, usage frequency, maintenance, and cost of operation as well as to investigate rider perception of the ideal arena properties using a large population of riders. Data on 656 equestrian surfaces in Sweden obtained up to 2014 are presented, of which 373 were outdoor and 283 were indoor arenas. Dressage and show-jumping were the main disciplines conducted in the arenas. Sand-mineral arenas were most common outdoors and sand-woodchips arenas most common indoors, followed by sand-fibre arenas and even fewer synthetic arenas. Comparing the three most common arena types, dragging was most often done on sand-woodchips and sand-fibre arenas. Harrowing was less often done on sand-mineral arenas compared to sand-woodchips and sand-fibre arenas. Combining dragging, harrowing, deep harrowing, and rolling, arenas with higher usage were maintained more frequently, compared to those used less frequently. It was commonly claimed that the top-layer needs renovation every other-4th year or every 5th to 10th year. Few respondents allocated more than 10,000 SEK in yearly maintenance costs, with the exception for sand-woodchips and sand-fibre arenas followed by synthetic arenas. The shortest duration perceived between required renovations was found for sand-woodchips top-layer arenas. Ideal surface properties were evaluated by 3,158 riders. Dressage and show-jumping riders differed somewhat regarding ideal spans of functional arena properties: for impact firmness, responsiveness, and grip. The current study likely included well-utilised arenas, compared to those less well-utilised. The resources necessary to keep an arena consistent over time seemed underestimated. Knowledge of maintenance and priorities for arenas are important to users and arenas managers, be they construction companies or arena managers in order to maximise the outcome of efforts for arena improvement and optimise locomotor health for horses that use them. Further, many arenas were new and research into organic arena management is important, especially if equestrians continue to build and renew arena surfaces.
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34.
  • Egenvall, Agneta, et al. (författare)
  • Visual lameness assessment in comparison to quantitative gait analysis data in horses
  • 2022
  • Ingår i: Equine Veterinary Journal. - : Wiley. - 0425-1644 .- 2042-3306. ; 54, s. 1076-1085
  • Tidskriftsartikel (refereegranskat)abstract
    • Background Quantitative gait analysis offers objective information to support clinical decision-making during lameness workups including advantages in terms of documentation, communication, education, and avoidance of expectation bias. Nevertheless, hardly any data exist comparing outcome of subjective scoring with the output of objective gait analysis systems. Objectives To investigate between- and within-veterinarian agreement on primary lame limb and lameness grade, and to determine relationships between subjective lameness grade and quantitative data, focusing on differences between (1) veterinarians, (2) live vs video assessment, (3) baseline assessment vs assessment following diagnostic analgesia. Study design Clinical observational study. Methods Kinematic data were compared to subjective lameness assessment by clinicians with >= 8 years of orthopaedic experience. Subjective assessments and kinematic data for baseline trot-ups and response to 48 diagnostic analgesia interventions in 23 cases were included. Between and within-veterinarian agreement was investigated using Cohen's Kappa (kappa). Asymmetry parameters for kinematic data ('forelimb lame pattern', 'hindlimb lame pattern', 'overall symmetry', 'vector sum head', 'pelvic sum') were determined, and used as outcome variables in mixed models; explanatory variables were subjective lameness grade and its interaction with (1) veterinarian, (2) live or video evaluation and (3) baseline or diagnostic analgesia assessment. Results Agreement on lame limb between live and video assessment was 'good' between and within veterinarians (median kappa = 0.64 and kappa = 0.53). There was a positive correlation between subjective scoring and measured asymmetry. The relationship between lameness grade and objective asymmetry differed slightly between (1) veterinarians (for all combined parameters, p-values between P < .001 and 0.04), (2) between live and video assessments ('forelimb lame pattern', 'overall symmetry', both P <= .001), and (3) between baseline and diagnostic analgesia assessment (all combined parameters, between P < .001 and .007). Main limitations Limited number of veterinarians (n = 4) and cases (n = 23), only straight-line soft surface data, different number of subjective assessments live vs from video. Conclusions Overall, between- and within-veterinarian agreement on lame limb was 'good', whereas agreement on lameness grade was 'acceptable' to 'poor'. Quantitative data and subjective assessments correlated well, with minor though significant differences in the number of millimetres, equivalent to one lameness grade between veterinarians, and between assessment conditions. Differences between baseline assessment vs assessment following diagnostic analgesia suggest that addition of objective data can be beneficial to reduce expectation bias. The small differences between live and video assessments support the use of high-quality videos for documentation, communication, and education, thus, complementing objective gait analysis data.
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35.
  • Egenvall, Agneta, et al. (författare)
  • Withers vertical movement asymmetry in dressage horses walking in different head-neck positions with and without riders
  • 2020
  • Ingår i: Journal of Veterinary Behavior: Clinical Applications and Research. - : Elsevier BV. - 1558-7878 .- 1878-7517. ; 36, s. 72-83
  • Tidskriftsartikel (refereegranskat)abstract
    • The superimposed influences of different head and neck positions (HNPs) and rider effects on symmetry in sound horses have not been studied. Our aim was to investigate the effects of HNPs and rider on thesymmetry in minimum height of the withers at the walk. Seven high-level dressage horses were studied with and without rider in six HNPs: HNP1, free position; HNP2, dressage competition position; HNP3,flexed poll position; HNP4, over-flexed position; HNP5, extended raised position; and HNP6, forward downward position. Kinematic and vertical ground reaction force data were recorded during 15 s trialson an instrumented treadmill. In mixed models, difference in the minimal height of the withers in earlyleft vs right forelimb stance was modelled as dependent variable. The more restricted HNP3 (T-values2.62 to 1.98, 118 DF,P¼0.001 to<0.05) and HNP5 (P¼0.002 to<0.05) were generally less symmetrical while unridden and more symmetrical while ridden, compared with the free (HNP1) or forward downward (HNP6) positions. Both with and without rider, when the withers dropped lower in earlystance of one forelimb, this was associated with shorter protraction at the start of stance in the ipsilateral hind limb, and shorter stance overlaps between this hind limb and the other limbs during diagonalsupport, 3-limb support with two forelimbs and one hind limb, and ipsilateral support. HNP effects on withers movement asymmetry differed between unridden and ridden conditions. The considerablevariation between horses stresses the need for trainers to use individualized training programs to address horse asymmetry.
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36.
  • Eisersiö, Marie, et al. (författare)
  • A snapshot of the training schedule for 8 professional riders riding dressage
  • 2015
  • Ingår i: Comparative Exercise Physiology. - 1755-2540 .- 1755-2559. ; 11, s. 35-46
  • Tidskriftsartikel (refereegranskat)abstract
    • The aim of this study was to document and categorise riding sessions, carried out by professional riders, by describing the riding sessions according to gait, ridden track, lateral movements, rider position in the saddle and rein length. These data were then analysed relative to horse and rider characteristics, e.g. educational level of horse and rider, time in training and laterality of the horse. Eight professional riders riding 3 familiar horses each participated in the study and the riders were asked to demonstrate their normal routine for flatwork/dressage with each horse. The whole training session was video recorded. Video recordings were scrutinised and data were categorised and analysed. Mixed models were used for the statistical analysis, including rider as random effect. The median length of the riding sessions were 31 min. The riders spent 38% of the riding session at the walk, 39% at the trot, 8% at left lead canter and 9% at the right lead canter. The riders devoted 28-29% of the riding session to riding straight, turning left and turning right and 8% to riding lateral movements. The ridden exercises performed and the duration of the exercises was to a large extent connected to the educational level of the horse and its time in training with the rider. More work at the canter and lateral movements at the trot were included for upper level horses compared to lower level horses. Horses in training for more than one year, compared to less than one year, were ridden for longer durations at the canter and shorter durations at the trot. The disposition of riding sessions needs further investigation. In particular, large scale epidemiological studies of orthopaedic injuries need to consider the daily riding sessions in detail.
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37.
  • Eisersiö, Marie, et al. (författare)
  • Movements of the horse's mouth in relation to horse-rider kinematic variables : a pilot study
  • 2013
  • Ingår i: Veterinary Journal. - : Elsevier BV. - 1090-0233 .- 1532-2971. ; 198, s. e33-e38
  • Tidskriftsartikel (refereegranskat)abstract
    • The objective of this pilot study was to investigate the influence of rein contact and the movement of the rider’s hand on the horse’s behaviour, analysing data on horses ridden in two different head and neck positions. We hypothesized that the rider’s hand movements and rein tension generate behavioural responses from the horse, and more so when ridden on the bit compared to free and unrestrained. Data were collected from seven dressage horses/riders in sitting trot on a high-speed treadmill. Kinematics were recorded using a 12-camera, infrared-based opto-electronic system. Behavioural recordings were made from video and three horses wore a rein tension meter. After stride split, data were standardised to 0-100% stride duration. Mixed models were used to analyse how the behaviours varied over the stride cycle; trial within horse was treated as a random effect, while percentage of stride, rein tension and kinematic variables mainly related to the rider’s hand were entered as fixed effects. Behaviours discerned were lip movement, mouth movement, open mouth, ear position, head tilt and tail movement. Mouth movements were associated with the suspension phase of the trot and percentage of stride was highly significant (P<0.0001). Head and neck position was non-significant in the final models, while rein tension and the distance between the rider’s hand and the horse’s mouth affected the amount of mouth movements. The results from this preliminary study convey the large variations between horses and riders, as well as the complexity of the interaction.
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38.
  • Eisersiö, Marie, et al. (författare)
  • Rein tension in 8 professional riders during regular training sessions
  • 2015
  • Ingår i: Journal of Veterinary Behavior: Clinical Applications and Research. - : Elsevier BV. - 1558-7878 .- 1878-7517. ; 10, s. 419-426
  • Tidskriftsartikel (refereegranskat)abstract
    • Rein tension signals are commonly used to communicate the intended speed, direction, and head carriage to the horse during horseback riding. Rein tension has previously been recorded relative to gait, exercises, and turning maneuvers. The aim of this study was to target the between-gait and between-exercise variation in rein tension, controlling for riders and horses within riders, the between-rein variation, and the general within-gait or exercise variation, during entire riding sessions. Eight riders with 3 horses each were included in the study and each horse was fitted with a custom-made rein tension meter fastened on leather reins. Rein tension data and video films were collected during the riding session, and the video films were scrutinized and categorized according to ridden exercises. Statistics used to model rein tension in mixed models were "median", area under curve, averages of 2 and 25 percentiles ("low") and of 75 and 98 percentiles ("high"), and the difference between 98 and 2 percentiles ("range"). Fixed effects were rein, gait, rider's position, horse level, and type of ridden exercise, and random effects were horse-side, rider, horse, and trial within horse. The analyses demonstrate substantial variation between gaits, rider position within gait, and between riders and horses. Considering data on short reins, the major determinants found for amount of rein tension was gait (walk [median 12 N both reins] < trot [median 14-19 N left/right rein and sitting/posting] < canter [median 1324 N left/right rein and sitting/light seat]) as well as the rider's position in the saddle for trot (posting [median 14 N both reins] < sitting [median 17 N/19 N left/right rein]) and canter (light seat [median 1317 N left/right rein and left/right canter] < sitting [median 20-24 N left/right rein and left/right canter]). Regarding the 2 reins; the right rein was the highest in comparisons in the "high" and "range" models, whereas the inside rein was the highest in canter. Riders contributed to most of the variation in the "median" and "low" models, whereas horses contributed the highest relative variance estimates in the models associated with high rein tension ("high" and "range"). Our results suggest that variables to consider in rein tension studies are the gait of travel, the rider's position in the saddle, the ridden exercise performed, the educational level of horse, the rider and horse per se, and to some extent the left or right rein. (C) 2015 The Authors. Published by Elsevier Inc.
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39.
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40.
  • Engell, Maria Terese, et al. (författare)
  • Head, trunk and pelvic kinematics in the frontal plane in un-mounted horseback riders rocking a balance chair from side-to-side
  • 2018
  • Ingår i: Comparative Exercise Physiology. - 1755-2540 .- 1755-2559. ; 14, s. 249-259
  • Tidskriftsartikel (refereegranskat)abstract
    • For efficient rider-horse communication, the rider needs to maintain a balanced position on the horse, allowing independent and controlled movements of the rider’s body segments. The rider’s balance will most likely be negatively affected by postural asymmetries. The aims of this study were to evaluate inter-segmental symmetry of movements of the rider’s pelvis, trunk, and head segments in the frontal plane while rocking a balance chair from side to side and to compare this to the rider’s frontal plane symmetry when walking. Frontal plane rotations (roll) of the pelvis, trunk and head segments and relative translations between the segments were analysed in twenty moderately-skilled riders seated on a balance chair and rocking it from side to side. Three-dimensional kinematic data were collected using motion capture video. Principal component analysis and linear regression were used to evaluate the data. None of the riders displayed a symmetrical right-left pattern of frontal plane rotation and translation in any of their core body segments. The intersegmental pattern of asymmetries varied to a high degree between individuals. The first three principal components explained the majority of between-rider variation in these patterns (89%). A significant relationship was found indicating that during walking, when foot eversion was present on one side, pelvic/trunk roll during rocking the chair was asymmetric and larger to that same side (P=0.02, slope=0.95 in degrees). The inter-individual variation in the rider’s intersegmental strategies when rocking a balance chair was markedly large. However, there was a significant association to the rider’s foot pattern while walking, suggesting consistent intra-individual patterns over multiple situations. Although further studies are needed to confirm associations between the findings in this study and rider asymmetry while riding, riders’ postural control can likely be improved and this may enhance their sport performance.
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41.
  • Engell, Maria Terese, et al. (författare)
  • Postural changes and their effects in elite riders when actively influencing the horse versus sitting passively at trot
  • 2016
  • Ingår i: Comparative Exercise Physiology. - 1755-2540 .- 1755-2559. ; 12, s. 27-33
  • Tidskriftsartikel (refereegranskat)abstract
    • The objectives were to compare sagittal plane posture of the pelvis, trunk and head of elite dressage riders when they ride actively to train the horse versus sitting passively and following the horses' movements at trot, and to evaluate the effects of these changes in rider posture on load distribution on the horse's back. Synchronised motion capture and saddle mat data of seven elite dressage riders were used to measure minimal and maximal angles and range of motion (ROM) for the pelvic, trunk and head segments, the angle between pelvis and trunk segments, phase-shift between pitching motions of pelvis and trunk, and pelvic translation relative to the saddle. Non-parametric statistical tests compared variables between the two rider postures. In the passive rider posture the pelvis, trunk and head showed two pitching cycles per stride. Maximal posterior and anterior pelvic rotation occurred, respectively, early and late in the horse's diagonal stance phase. Compared with pelvic movements, trunk movements were slightly delayed and head movements were out-of-phase. In the active rider posture the pelvis and trunk pitched further posteriorly throughout the stride. Most of the riders showed similar sagittal plane movements of the axial body segments but with some notable individual variations.
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42.
  • Hernlund, Elin, et al. (författare)
  • Comparing subjective and objective evaluation of show jumping competition and warm-up arena surfaces
  • 2017
  • Ingår i: Veterinary Journal. - : Elsevier BV. - 1090-0233 .- 1532-2971. ; 227, s. 49-57
  • Tidskriftsartikel (refereegranskat)abstract
    • The development of safety and quality standards for equestrian surfaces needs to be based on objective, repeatable measurements which allow comparisons between surfaces. These measurements should incorporate the assessment of surface performance by riders. This study provides data from objective and subjective assessment of functional properties of high-level show jumping competition and warm-up arenas. Twenty-five arenas in nine international show jumping events were evaluated by mechanical in situ testing with a surface tester, rider assessments using visual analogue scales (198 riders provided 749 arena evaluations), descriptions of arena constructions and by laboratory tests of surface material. Mixed models were used to present subjective evaluation of rider perception of the functional properties for each arena while controlling for rider and event. The association between objective and subjective assessments were also explored creating mixed models, controlling for rider and event.Mechanical measurements of impact firmness, and to a lesser extent cushioning and grip, had a significant positive association with the riders' perception. Responsiveness as assessed by the Orono biomechanical surface tester (OBST) was negatively associated with the riders' perceptions, which suggests riders and the OBST had different concepts of this functional property and that further developments of the OBST might be necessary. Objectively measured uniformity showed no useful association with riders' perception. Even though arena assessments were made by top level riders, a substantial inter-rider variation was demonstrated. (C) 2017 The Authors. Published by Elsevier Ltd.
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43.
  • Hernlund, Elin, et al. (författare)
  • Effect of superficial harrowing on surface properties of sand with rubber and waxed-sand with fibre riding arena surfaces: a preliminary study
  • 2015
  • Ingår i: Veterinary Journal. - : Elsevier BV. - 1090-0233 .- 1532-2971. ; 203, s. 59-64
  • Tidskriftsartikel (refereegranskat)abstract
    • A recent epidemiological study identified various aspects of arena surfaces and arena surface maintenance that were related to risk of injury in horses and that arena maintenance is important in reducing injury risk. However, there has been little research into how properties of arena surfaces change with harrowing. This study aimed to compare the properties of different arena surface types pre- and post-harrowing. The Orono Biomechanical Surface Tester fitted with accelerometers and a single- and a three-axis load cell was used to test 11 arenas with two different surfaces types, sand with rubber (SR) and waxed-sand with fibre (WSF). Three drop tests were carried out at 10 standardised locations on each arena. Mixed models were created to assess the effect of surface type, pre- or post-harrowing, and drop number on the properties of the surface, including maximum horizontal deceleration, maximum vertical deceleration, maximum vertical load and maximum horizontal load.Post-harrowing, none of the parameters were altered significantly on SR. On WSF, maximum vertical deceleration and maximum vertical load significantly decreased post-harrowing. The differences in the effects of superficial harrowing on SR and WSF could be attributed to the different compositions and sizes of the surface material. The results suggest that different maintenance techniques may be more suitable for different surface types and that the effects of superficial harrowing are short-lived due to the rapid re-compaction of the surface with repeated drops on WSF. Further work is required to determine the effects of other maintenance techniques, and on other surface types. (C) 2014 Elsevier Ltd. All rights reserved.
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44.
  • Hernlund, Elin, et al. (författare)
  • Equestrian surfaces – a guide
  • 2014
  • Bok (populärvet., debatt m.m.)abstract
    • Equestrian arena surfaces are a major investment for stable owners, riding clubs and private horse owners. With the growth of equestrian sport in recent decades, both in terms of financial turnover and number of participants, demands on and expectations on equestrian surfaces have increased. Surfaces are expected to promote both performance and soundness. Scientific testing of equine surfaces was first developed within Thoroughbred and Standardbred racing, where for decades scientists have studied associations between orthopaedic injury and surface properties. The background of biomechanical research into equine surfaces is described in more detail in the foreword. Thanks to these studies the information in this guide is supported by scientific data and on-going research. The guide also utilises advice from international arena consultants and equestrian professionals with years of practical experience of building and maintaining surfaces. The guide is aimed at those who want to build or renovate a riding arena, or those who require more knowledge about riding surfaces. Furthermore the guide provides advice on building and maintaining an indoor or outdoor arena. Many equestrians discuss and want an answer to what is ”the best” riding surface. As this guide shows, it is wiser to talk about a ‘surface that is most suited to your and your horse’s needs’, and that how well it works will also depend on how you treat it.
  •  
45.
  • Hernlund, Elin, et al. (författare)
  • Hoof accelerations at hoof-surface impact for stride types and functional limb types relevant to show jumping horses
  • 2013
  • Ingår i: Veterinary Journal. - : Elsevier BV. - 1090-0233 .- 1532-2971. ; 198, s. E27-E32
  • Tidskriftsartikel (refereegranskat)abstract
    • Increased knowledge of the influence of stride type on hoof impact accelerations for fore and hind limbs could lead to a more complete picture of hoof–ground interactions in equine athletes. Hoof accelerations were quantified for each hoof of five show jumping horses using two orthogonal single axis ± 250 g accelerometers. Accelerations were recorded when cantering horses jumped fences of varying types (upright and oxer) and heights (90–130 cm) on three different surface conditions. Strides were identified as normal canter strides, take-off strides and landing strides. Descriptive hoof impact parameters were maximal vertical deceleration (MaZ), range of maximum fore-aft acceleration and deceleration (RaX), quotient of acceleration vectors (arctangent for RaX/MaZ) and hoof breaking duration (time from MaZ to first level of <0.042 g absolute fore-aft acceleration). The highest hoof impact accelerations occurred during the takeoff stride (mean MaZ over limbs 52.6–91.6 g vs. all-stride mean 39.8 g; mean RaX 63.9–80.5 g vs. all-stride mean 50.7 g). At the jump landing, the forelimbs also experienced high MaZ (46.8 and 49.0 g) of the same order of magnitude as the forelimbs at the take-off. Non-lead limbs had higher MaZ in the normal canter stride, comparing within forelimb and hind limb pairs, and the reverse relationship occurred for RaX and for the quotient of acceleration vectors. The systematic variation introduced by limb and stride type suggests that these gait parameters are important to understand in a sport-specific context for horse surfaces, especially in the development of standardised testing equipment that simulates horse–surface interactions.
  •  
46.
  • Hernlund, Elin, et al. (författare)
  • Kinematic characteristics of hoof landing in jumping horses at elite level
  • 2010
  • Ingår i: Equine Veterinary Journal. - : Wiley. - 0425-1644 .- 2042-3306. ; 42, s. 462-467
  • Tidskriftsartikel (refereegranskat)abstract
    • The landing and braking characteristics of the hooves varied substantially between hind-, fore-, trailing and leading limbs. Developing mechanical testing devices for arena surfaces, this fairly wide range of biomechanical events must be considered, in order to simulate the horse-surface interaction.
  •  
47.
  • Hernlund, Elin, et al. (författare)
  • Modelling fore- and hindlimb peak vertical force differences in trotting horses using upper body kinematic asymmetry variables
  • 2022
  • Ingår i: Journal of Biomechanics. - : Elsevier BV. - 0021-9290 .- 1873-2380. ; 137
  • Tidskriftsartikel (refereegranskat)abstract
    • Differences in peak vertical ground reaction forces (dFzpeak) between contralateral forelimbs and hindlimbs are considered the gold standard for quantifying weight-bearing lameness. However, measuring kinematics for the same purpose is more common and practical. Vertical movement asymmetries (VMA) of the horse's upper body have previously been correlated to fore- and hindlimb lameness. But the combined response of head, withers and pelvis VMA to fore- and hindlimb dFzpeak has not yet been thoroughly investigated. Deriving the kinetic responses from kinematics would help the interpretation and understanding of quantified weight-bearing lameness.In this retrospective study, 103 horses with a wide range of fore- and hindlimb dFzpeak had been trotted on a force-measuring treadmill synchronized with an optical motion capture system. VMA of the head, withers and pelvis as well as dFzpeak were extracted. Multiple linear mixed models and linear regressions of kinematic variables were used to model the dFzpeak. It was hypothesised that all included VMA would have a significant influence on the dFzpeak outcome variables.The results showed a complex relationship between VMA and dFzpeak where both amplitude and timing of the VMA were of importance. On average, the contribution percentage of VMA to fore/hind dFzpeak were 66/34% for head, 76/24% for withers and 33/67% for pelvis. The linear regressions for the fore/hindlimb models achieved mean measurement root mean squared errors of 0.83%/0.82% dFzpeak. These results might help determine the clinical relevance of upper body VMA and distinguish between primary fore, hind, ipsilateral and diagonal weight-bearing lameness.
  •  
48.
  •  
49.
  • Hjernö, K, et al. (författare)
  • Down-regulation of the strawberry Bet v 1-homologous allergen in concert with the flavonoid biosynthesis pathway in colorless strawberry mutant
  • 2006
  • Ingår i: Proteomics. - : Wiley. - 1615-9861 .- 1615-9853. ; 6:5, s. 1574-1587
  • Tidskriftsartikel (refereegranskat)abstract
    • Proteomic screening of strawberry (Fragaria ananassa) yielded a 58% success rate in protein identification in spite of the fact that no genomic sequence is available for this species. This was achieved by a combination of MALDI-MS/MS de novo sequencing of double-derivatized peptides and indel-tolerant searching against local protein databases built on both EST and full-length nucleotide sequences. The amino acid sequence of a strawberry allergen, homologous to the well-known major birch pollen allergen Bet v 1, was partially determined. This strawberry allergen, named Fra a 1 according to the nomenclature for allergen proteins, showed sequence identity of 54 and 77%, respectively, with corresponding allergens from birch and apple. Differential expression, as evaluated by 2-D DIGE, occurred in 10% of protein spots when red strawberries were compared to a colorless (white) strawberry mutant. White strawberries, known to be tolerated by individuals affected by allergy, were found to be virtually free from the strawberry allergen. Also several enzymes in the pathway for biosynthesis of flavonoids, to which the red color pelargonidin belongs, were down-regulated. This approach to assess differential protein expression without access to genomic sequence information can also be applied to other crop plants and phenotypic traits.
  •  
50.
  • Jansson, Anna, et al. (författare)
  • Locomotion asymmetry in young Standardbred trotters in training and links to future racing career
  • 2022
  • Ingår i: Comparative Exercise Physiology. - 1755-2540 .- 1755-2559. ; 18, s. 85-92
  • Tidskriftsartikel (refereegranskat)abstract
    • This study evaluated whether front and hind limb symmetry patterns observed from 1.5 through 3 years of age in Standardbred trotters in training affect racing activity at older age. The hypothesis tested was that asymmetries observed during this period are linked to reduced number of lifetime races and low earnings. Sixteen Standardbreds were subjected to a controlled training and dietary programme from the age of 1.5 years until December as 3-year-olds (P1) and then continued their career with other trainers. On 17 occasions during P1, locomotion asymmetry (vector sum) in front and hind limbs during trot in hand was recorded with a sensor-based system. By 10 years of age, data on lifetime number of races and earnings of the horses were obtained from the Swedish Trotting Association. Horses were divided in groups based on the number of lifetime races performed, i.e. more or less than the median of the cohort born the same year. Mean asymmetry levels did not differ between horses performing more or less lifetime races than the cohort median. However, horses that showed the poorest lifetime race activity showed elevated hind limb asymmetry in August at the age of 3 years, compared to horses with more races (group median: 6±2 mm (P=0.02)). There were no correlations between individual mean and peak asymmetries and lifetime earnings. It is concluded that locomotion symmetry observed during trot in hand at the age of 1.5-year-olds to December as 3-year-olds was not a simple and straight-forward predictor of future racing career. However, hind limb asymmetries of around 10 mm in the late season as 3-year-olds could be a warning of impaired future performance.
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