bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetics of the Forelimb in Horses Trotting an Uphill and Downhill Slope
Authors: Chateau H , Camus M , Holden‐Douilly L , Lepley J , Falala S , Ravary B , Vergari C , Denoix JM , Pourcelot P , Crevier‐Denoix N
Published: June 2014

Introduction

Equine training often includes running on tracks with different uphill (UP) or downhill (DOWN) slopes and examination of lame horses on a slope can be used to investigate the origin of lameness. However little is known about the kinetics of horses in such circumstances. The aim of this study was to quantify and compare ground reaction force, acceleration and sliding of the hoof in the forelimb of horses trotting an uphill and downhill slope.

Methods

The right front hoof of 5 horses was equipped with a dynamometric horseshoe and an accelerometer allowing the measurement of 3D ground reaction force and hoof acceleration and displacement. The horses were trotted in hand (3.5 m/s) on a 7% inclined asphalt area successively uphill and downhill. Data were analysed using an ANOVA, accounting for correlated repeated measurements within each horse (P<0.01).

Results

Speed was not significantly different between UP and DOWN. The maximal longitudinal breaking force of the hoof, maximal vertical force, vertical impulse and longitudinal sliding of the hoof at impact were significantly increased on DOWN compared to UP (respectively +97.7%, +8.4%, +16.6% and +450%). Stride frequency and longitudinal propulsive force were significantly decreased on DOWN compared to UP (respectively −5.1% and −48.7%).

Conclusions

The results of this study (increased longitudinal breaking force and maximal vertical force on a downward slope) are consistent with previous measurements of superficial digital flexor tendon loading on the same area [1]. Conversely increased propulsive force on an uphill slope needs to be taken into account during rehabilitation of horses with deep digital flexor tendon injuries.

Ethical Animal Research

The local Animal Care and Ethics Committee advised that no formal approval was required for this study. Sources of funding: Conseil Régional de Basse‐Normandie, the Fonds Unique Interministériel, the French Ministry of Agriculture, the FEDER and the Institut Français du Cheval et de l'Equitation (IFCE). Competing interests: none.
Comparison of the Loading of Leading and Trailing Forelimbs in Horses at Landing
Authors: Crevier‐Denoix N , Camus M , Falala S , Martino J , Pauchard M , Ravary‐Plumioen B , Desquilbet L , Denoix JM , Chateau H , Pourcelot P
Published: June 2014

Introduction

The objective was to compare, using a dynamometric horseshoe (DHS), the longitudinal and vertical components of the reaction force and corresponding impulses in the leading and trailing forelimbs of horses landing after a jump on a competition surface.

Methods

Both forefeet of 3 horses were equipped with a DHS. 1000 Hz films of the right forefoot at landing were synchronized with the DHSs recordings. Within a corridor delimited on a sand arena, each horse jumped a 1.20 m (horse 1) or 1.10 m (horses 2 and 3) high fence while cantering alternatively at both leads. Data were pooled and 37 strides analyzed both for the leading (LF) and trailing (TF) forelimbs. In addition to peak forces and impulses (integral of force over time) in the hoof reference frame, the forces on the right forelimb were projected in the track reference frame to determine true retardatory (TR) and propulsory (TP) phases. Differences between LF and TF were estimated with linear regression models, using generalized estimating equations to adjust for correlated repeated measurements within each horse (for all results, P<0.0005).

Results

Maximal vertical force and loading rate were respectively 1.2 and 1.4 times higher on TF. TR‐longitudinal impulse was 21 times, and TR‐vertical impulse 8 times higher in LF, whereas TP‐longitudinal impulse was 4 times, and TP‐vertical impulse 2 times higher in TF.

Conclusions

Despite a lower maximal vertical loading, LF plays a major part in the retardatory (load‐absorption) phase, while TF is mainly involved in propulsion. Loading of anatomical structures is therefore different in both limbs, which provides insights for interpreting horses' preferred lead at landing depending on which structure is affected.

Ethical Animal Research

The local Animal Care and Ethics Committee advised that no formal approval was required for this study. Sources of funding: Région Basse‐Normandie, the FEDER, the Fonds Eperon and the IFCE. Competing interests: none.
The Hoof Renewal Time of Thoroughbred Foals from Birth
Authors: Curtis S , Martin J , Hobbs S
Published: June 2014

Introduction

Thoroughbred foals are born with fully developed hooves and stand within minutes. A ring in the horn occurs at birth and grows down the hoof wall, marking the fetal hoof (distal) and foal hoof (proximal). Birth rings in hoof horn have been noted in other species and used to estimate age. Hoof wall renewal in all ages of horse has been poorly reported; horn growth and complete hoof capsule renewal has not been measured in Thoroughbred foals. Partial hoof wall avulsions are relatively common. The objective was to measure the time taken for the fetal hoof of a newborn foal to grow out and be replaced by hoof grown since birth.

Methods

Thoroughbred foals (N = 150) on four Newmarket stud farms were studied during June to September. The age of the foal and the day that routine hoof trimming removed the remnants of the fetal hoof of the front hooves was recorded. Foals that were on restricted exercise, ill or where the remnants of the fetal hoof still remained after trimming were excluded from the data. 45 foals fulfilled the criteria. The data were tabulated in Excel, analysed in Minitab and assessed for normality (Anderson‐Darling).

Results

The mean age at which the fetal hoof grew out was 145 ± 15 days (95% confidence interval, 141.77–147.16).

Conclusions

Thoroughbred foals replace the fetal hoof at twice the speed given for mature horses (270–365 days). Knowing the time of hoof renewal will allow accurate predictions of healing to be made in cases of partial hoof wall avulsion and other hoof lesions.

Ethical Animal Research

Approval was given by the University of Central Lancashire Animal Projects Committee. Explicit owner informed consent for participation in this study is not stated. Sources of funding: none. Competing interests: none.
Subjective Evaluation of Lameness in Horses During Lungeing
Authors: Hammarberg M , Egenvall A , Rhodin M
Published: June 2014

Introduction

Lungeing is an important part of lameness examination since the circular path is thought to accentuate low‐grade lameness. Circle dependent, compensatory movement, and pain related asymmetries make lameness evaluation complex. Subjective evaluation, by watching the horse in motion, is standard practice but studies have shown that inter‐observer variation is high when assessing lameness (straight line movement). The aim was to estimate inter‐ and intra‐rater agreement between equine practitioners evaluating lameness from videos of sound and lame horses during lungeing.

Methods

Equine practitioners (n = 86), including 43 deemed as experienced, participated in a web‐based survey. Horses (n = 23, including two horses with solar‐pressure induced lameness) [defined as forelimb‐, hind limb‐lame or sound from objective kinematic straight line measurements] trotted on a circle in both directions on soft/hard ground surfaces (one condition/video). Of 104 recordings, 60 were selected of which 10 were repeated (numbers chosen to make compliance possible). The practitioners were asked to report which limb was most lame on each video. Kappa statistics were used to analyze the inter‐rater and intra‐rater agreement. The κ agreement was set to poor <0.3, acceptable 0.31–0.5, good 0.51–0.8, excellent >0.8.

Results

Inter‐rater agreement kappa (n = 86) was 0.31 (0.38/0.25 for experienced/less experienced). Evaluating forelimb compared to hind limb lameness agreement increased 11%. Intra‐rater agreement kappa (percentiles) was (P10‐50‐90, 0.21, 0.57, 0.84).

Conclusions

Since identification of the lame limb/limbs is a prerequisite for successful diagnosis, treatment and recovery, the high inter‐observer variation when evaluating lameness during lungeing may decrease the accuracy of lameness examinations.

Ethical Animal Research

The experimental procedures were approved by a local Ethical Committee on Animal Experiments (Uppsala, Sweden), and there was a written consent from the horse owners. Sources of funding: Swedish‐Norwegian Foundation for Equine Research. Competing interests: none.
What do Riders Want from an Arena Surface?
Authors: Holt D , Northrop A , Martin J , Daggett A , Hobbs S
Published: June 2014

Introduction

Rider preference appears to be a large factor determining the selection of an arena surface. The negative reaction of the competitors to the surface used for the Olympic test event in 2011 was sufficient to initiate a change in the surface composition used for the Olympic equestrian events in 2012. The aim of this study was to quantify surface characteristics that riders perceive to be the most favoured in a training and competition venue.

Methods

A survey was used to ask riders (n = 342) to describe characteristics that they liked about their favourite venue across Northern England. The two most popular surfaces (both well‐established wax, sand and fibre) were harrowed before being measured at several plots. An Orono Biomechanical Surface Tester and traction device were used to compare the functional properties of the two surfaces. The respondent's reasons for choosing their favourite venue were associated with specific surface measures including peak load, rebound timing and traction. A Mann‐Whitney U test was used to establish differences between venues.

Results

The favourite venue was selected because the surface was not too deep or slippery and provided good support, spring and cushioning. The peak load (P = 0.002) and traction (P>0.001) were significantly higher on the favourite surface compared to the second favourite (18.99 kN vs.17.29 kN and 20 Nm vs.19 Nm respectively).

Conclusions

Higher peak load values may be responsible for supporting a good performance and higher traction values could explain why riders felt that the surface was not ‘slippery’, although this may have negative effects on the horse. The results suggest there is potential to quantify rider preferences.

Ethical Animal Research

The study was approved by an ethics committee at the University of Central Lancashire (reference number: BuSH 057). Sources of funding: A student internship was awarded by the University of Central Lancashire. Competing interests: none.
An Investigation Into the Relationship of Pelvic Misalignment with Forelimb Hoof Size
Authors: Ireson A , Cunliffe C
Published: June 2014

Introduction

The study aim was to determine whether there is a link between pelvic misalignment and uneven forelimb hoof size. Previous research suggests that increased loading increases hoof size, but correlation with pelvic misalignment is unknown.

Methods

30 healthy, sound, multidiscipline horses, regularly shod/trimmed every 6 weeks, were assessed. Tuber coxae heights were measured in triplicate from the dorsal aspect to ground level, with the horse standing square, using a plumb line and measuring stick. Difference between means indicated value and direction of pelvic misalignment. Using a 300 mm digital vernier calliper, triplicate measurements of hoof width (lateral to medial edge) and hoof length (dorsal to palmar edge) were made of both fore‐feet, prior to and after farrier trimming, and were obtained by the farrier (blinded to pelvic measurements) at two shoeing intervals 6 weeks apart. Both methods were tested for reliability and repeatability to ± 1 mm. Statistical analyses included Chi‐square, symmetry indices and one‐way ANOVA.

Results

Ventral pelvic rotation was related to greater growth in hoof width on the contralateral forelimb and greater growth in hoof length on the ipsilateral forelimb. There was a significant relationship between uneven hoof width and pelvic rotation direction (P = 0.0002), and a significant relationship between uneven hoof length and pelvic rotation directional (P = 6.1 x 10‐7). There was a significant relationship between amount of growth in hoof width (P = 0.0002) and hoof length (P = 4.8 x 10‐6) with pelvic misalignment.

Conclusions

This study provides evidence of a statistically significant relationship between the alignment of the pelvis and growth of horse's front hooves. Further study would be beneficial in enhancing understanding of the chain of compensatory effects on the equine body.

Ethical Animal Research

Procedures were reviewed by the McTimoney Chiropractic College Ethical Review Committee. Explicit owner informed consent for participation in this study is not stated. Sources of funding: none. Competing interests: none.
Preliminary Investigations Into Photogrammetric Measurement of Hoof Shape
Authors: Malone S , Jazayeri I , Davies H
Published: June 2014

Introduction

Advances in close‐range photogrammetry offer an option for high accuracy measurements of the equine hoof. Automatic camera calibration using coded targets, image matching and triangulation enables 3D model reconstruction from photographs. This study aimed to identify an accurate photogrammetric method to measure proximal hoof circumference (PHC). PHC is currently measured by hand and shown to change in racehorses during training.

Methods

A cadaver hoof was measured by hand, photographed, and laser scanned for method comparison. Then, the left front hooves of two adult horses were photographed under two treatments (exercise and control). Exercise involved 5 minutes brisk trot counter‐clockwise on a lunge‐line. During both experiments a Canon 40D camera (28–135 mm lens; F5 aperture; 1/60 sec shutter speed) was used. Hooves were marked with permanent marker and coded targets placed on the ground around the hoof for automatic point identification. Photos were taken from 10–16 different locations around the hoof. A paired t‐test was used for comparisons and significance set at P<0.05.

Results

Photogrammetry produced a 3D model of the cadaver hoof which was considered good (accuracy of 0.25 pixel RMS). Points on the hoof were manually identified and model creation took 1.5 hours. PHC measurements from photogrammetry differed from the laser scan by 1.25 mm and from hand measurements by 1.73 mm. PHC decreased following exercise (0.8 mm; p = 0.25).

Conclusions

Close‐range photogrammetry could be viable for highly accurate and quick measurements of hoof shape. Advantages include; ease of data acquisition, flexibility, low cost, evaluation of the loaded hoof, and high geometric accuracy. To measure only PHC eight images or less could be used. Additional research is required to determine repeatability and accuracy.

Ethical Animal Research

Procedures were approved by the University of Melbourne's Animal Welfare and Ethics Committee. Sources of funding: University of Melbourne. Competing interests: none.
Preliminary Assessment of Dressage Asymmetry within Sitting Trot and Shoulder‐in
Authors: Baxter J , Hobbs S , Chohan A
Published: June 2014

Introduction

Despite dressage popularity, little research exists in relation to the rider's posture and effect on aids given to the horse. The aim was to investigate asymmetry during sitting trot and shoulder‐in between varying rider abilities.

Methods

Full body kinematics were collected at 120 Hz (XSENS MVN Biomech) for 10 novice (age 28 ± 12 years, height = 168 ± 7 cm) and 10 advanced (age 29 ± 6 years, height = 163 ± 4 cm) predominantly right handed participants, with one left handed rider in each group. Range of motion for right hip, left hip, right knee, left knee, right ankle, left ankle, ASIS vertical movement, trunk rotation were generated in Visual 3D.

Results

Independent t‐tests demonstrated significant differences between groups within right and left hip external rotation when straight (P < 0.001, d = 2.52; P = 0.02, d = 1.25), shoulder‐in right (P = 0.01, d = 1.47; P = 0.02, d = 1.31), only significant in right hip within shoulder‐in left (P = 0.01, d = 1.30). Axial rotation to the right was found in all conditions, with the range significantly (P<0.05) increased between groups in straight and shoulder‐in right, as did right ASIS vertical excursion when riding straight (P = 0.01, d = 1.90), and left ASIS excursion within shoulder‐in left (P = 0.04, d = 1.03).

Conclusions

Right trunk axial rotation is considered closely linked to right hand dominance, rotating the rider's trunk to the dominant rein aid. Left shoulder‐in scored higher which may be because right trunk rotation is one of the aids given to the horse when executing this dressage movement.

Ethical Animal Research

Study protocols approved by the University of Central Lancashire, before commencing the study. Sources of funding: none. Competing interests: none.
Effect of an Oral Joint Supplement on Orthopaedic Evaluation Scores and Limb Kinematics
Authors: Murray R , Walker V , Tranquille C , Adams V , Frost R
Published: June 2014

Introduction

Numerous oral joint supplements are available, but there is limited research into their efficacy. This study evaluated the effect of an oral joint supplement on orthopaedic evaluation scores and limb kinematics in horses.

Methods

24 mature horses (71% 1–4/10 lame) were included. Exclusions were poor body condition, health problems, or lameness >4/10. Supplement S (FlexAbilityTM, Science Supplements, containing chondroitin sulphate 162 g/kg, glucosamine 190 g/kg, vitamin C 80 g/kg, methyl sulphonyl methane 256 g/kg, DHA 66 g/kg); EPA 34 g/kg; or placebo P (carrier/flavours only) were fed to horses for 21 days each in a random order triple‐blind crossover design. Horses were evaluated at day 0 (baseline), 21 (after first treatment) and 42 (after second treatment). Clinical orthopaedic evaluation for straight line and lungeing circle (walk and trot), and during ridden exercise (walk, trot and canter) was performed. Side‐view high‐speed motion‐capture (240 Hz) determined midstance tarsal flexion, carpal extension and fetlock extension for straight line trotting. All evaluators were blinded to treatment. Effect of treatment, sequence, limb and interactions were investigated using linear mixed models.

Results

S was associated with significantly lower lameness grade in a straight line (P = 0.001) with individual horses improving up to 2/10 grades and circle (P = 0.010) than either P or baseline. For horses with hindlimb lameness, supplement S was associated with significantly greater tarsal flexion than baseline (4.2% greater, P<0.02) or P (2.7% greater, P<0.037).

Conclusions

Oral administration of supplement S was associated with less lameness than P or baseline. Increased midstance tarsal flexion of lame limbs may indicate improved mobility or comfort during peak loading.

Ethical Animal Research

Explicit owner informed consent for participation in this study is not stated. Sources of funding: World Horse Welfare, Science Supplements. Competing interests: Rebecca Frost is employed by Science Supplements. Vicki Adams and Rachel Murray are involved with Science Supplements on a consultancy basis.
The Effect of Training on Stride Parameters in a Cohort of 40 Two Year Old Racehorses
Authors: Parkes R , Pfau T , Weller R , Witte T
Published: June 2014

Introduction

The biomechanical effects of training on gait in the Thoroughbred are not fully understood. We aimed to assess the effect of training, surface and incline on stride parameters.

Methods

40 two‐year‐old Thoroughbred racehorses entering training were recruited and followed from December 2012 until September 2013. Gait analysis was performed at eleven time points by equipping each horse with an inertial measurement unit (IMU) with inbuilt GPS, mounted on the dorsum immediately caudal to the most caudal palpable lumbar dorsal spinous process. Horses were exercised as per their regular training regimen on a variety of training surfaces and inclines. Data were analysed using custom software written in Matlab (Mathworks, UK), and statistical analysis was performed using R (R Foundation for Statistical Computing, Austria). A linear mixed model was used, with horse as a random effect and weeks in training, training surface, curve and incline as fixed effects.

Results

A total of 85,497 strides at speeds of between 6.00 and 19.03 ms‐1 were analysed. Stride length increased by 0.33 m ± 4.3 x 104 with each 1 ms‐1 increase in velocity. Training causes a reduction in stride length of 0.004 ± 0.0001 m per week and an increase in stride frequency of 1.29 x 103 ± 4.1 x 105 per week. Shallow inclines, steep inclines and declines cause a decrease in stride length of 0.07 ± 0.003 m, 0.10 ± 0.005 m and 0.04 ± 0.004 m respectively. Turf and peat moss training surfaces caused an increase in stride length of 0.03 ± 0.004 m and 0.06 ± 0.007 m respectively.

Conclusions

This study provides an insight into the effects of external factors on the gait of young Thoroughbreds in training. Ongoing research will further investigate these effects and interactions.

Ethical Animal Research

The study was approved by the local ethics committee. Explicit owner informed consent for participation in this study is not stated. Sources of funding: Horserace Betting Levy Board. Competing interests: none.
Effect of Pelvic Tilt on Synchronisation and Stability of Riders in Sitting Trot
Authors: Pettit I , Walker V , Tranquille C , Spear J , Murray R
Published: June 2014

Introduction

Rider movement may influence horse‐rider interaction, yet little is known about what physical attributes affect postural stability. This study aimed to compare pelvic control and postural stability of riders on the floor and whilst riding.

Methods

33 riders were assessed by a physiotherapist and subjectively graded according to ability to tilt the pelvis in isolation: 1 = poor, 2 = better plus compensations, which were either A = lumbar spine inclusion B = full body lean, 3 = good. Riders wore markers on (1) greater trochanter of the femur, (2) iliac crest, (3) greater tubercle of the humerus. A marker was placed over the horse's tuber sacrale (4). Two‐dimensional high‐speed motion‐capture (240 Hz) recorded four strides of collected sitting trot in a straight line from the left side. Distance between markers was measured at midstance, maximum hindlimb protraction and retraction. Synchronisation was determined by the difference in time (secs) between the tuber sacrale of the horse and pelvis of the rider at these stride points. One‐way ANOVA was used to compare synchronisation between groups. Student's independent t‐test was used to compare marker distance.

Results

For pelvic tilt, no grade 3 riders were seen. Grade 2 riders were more synchronised with the horse during left hind diagonal suspension phase (P = 0.011) and had smaller horizontal distances between markers 1–2, 2–3 and 1–3 respectively at all points of the stride (midstance: P<0.042; hindlimb protraction: P<0.049; hindlimb retraction: P<0.013). Comparing compensation types, grade A riders were better synchronised with the horse at midstance phase (P = 0.014).

Conclusions

Results suggest that control of pelvic movement may have an impact on horse‐rider synchronisation.

Ethical Animal Research

This project was approved by the Animal Health Trust Clinical Research Ethics Committee. Explicit owner informed consent for participation in this study is not stated. Sources of funding: The Elise Pilkington Charitable Trust, British Dressage and Dr. Bechtolsheimer. Competing interests: none.
The Effect of Noseband Tightness on Tensile Forces While Using Side Reins on Horses
Authors: Pospisil K , Potz I , Peham C
Published: June 2014

Introduction

The fixation of the bridle, particularly the noseband, is important in the horse‐rider interaction. The goal of this study was to show the influence of noseband tightness on tensile forces elicited in side reins under traction to position the horse's head.

Methods

Ten Warmblood horses (2 mares, 8 geldings; mean age: 12.4 ± 5.3 years) were assessed during walk and trot on a treadmill. Side reins were used to position the horse's head so that the nose was nearly vertical. Measurements were made with a correctly tightened noseband (two fingers space between the noseband and nasal bone = N1) and with a tight noseband (= N2). Rein forces were measured with an electronic sensor based on a force sensing resistor (27 g, sample rate 120 Hz, Interlink Electronics corp.), synchronized with a kinematic system (10 cameras, 120 Hz, Motion Analysis corp.). The force sensors were calibrated with masses of 1 Kg (=9.81 N) and 4 Kg (=39.24 N). Statistical analysis was performed using the software SPSS. Normality of data was checked with the Kolmogorov‐Smirnov‐test and data were analysed with repeated measures ANOVA (P<0.05).

Results

Side rein forces in N1 were significantly higher than in N2 during walk and trot. Maximum forces at walk were 8.6 ± 0.9 N for N1 and 6.7 ± 0.95 N for N2. At trot the forces (7.2 ± 0.95 N for N1; 5.96 ± 0.9 N N2) were significantly reduced compared to walk. There was no significant difference between left and right rein forces.

Conclusions

This study demonstrated that noseband tightness has an influence on rein tension. The rein forces that were exerted were lower than in ridden horses.

Ethical Animal Research

This study was approved by the local ethics commission. Sources of funding: University of Veterinary Medicine of Vienna. Competing interests: none.
The Effect of Two Different Bits on Tensile Forces in Side Reins
Authors: Potz I , Pospisil K , Peham C
Published: June 2014

Introduction

The effect of bits on the mouth of the horse is a source of controversy in animal welfare discussions. The goal of this study was to determine the influence of two different bits on tensile forces in side reins applied to exercising horses.

Methods

Ten Warmblood horses (2 mares, 8 geldings; mean age: 12.4 ± 5.3 years) were assessed during walk and trot on a treadmill. Side reins were used to position the horse's head so that the nose was nearly vertical. Two different bits were utilised: a double jointed snaffle (bit 1) and a mullen mouth snaffle (bit 2). Rein forces were measured with an electronic sensor based on a force sensing resistor (27 g, sample rate 120 Hz, Interlink Electronics corp.), synchronized with a kinematic system (10 cameras, 120 Hz, Motion Analysis corp.). The force sensors were calibrated with masses of 1 Kg (=9.81 N) and 4 Kg (=39.24 N). Statistical analysis was performed using the software SPSS. Normality of data was checked with the Kolmogorov‐Smirnov‐test and data were analysed with repeated measures ANOVA (P<0.05).

Results

Maximum tensile forces differed significantly between the two bits. Maximum forces at walk were 16 ± 1.9 N using bit 1 and 15.7 ± 1.9 N using bit 2. At trot the forces (12.7 ± 2.0 N bit 1; 10.4 ± 1.8 N bit 2) were significantly reduced compared to walk. There was no significant difference between left and right rein forces.

Conclusions

The type of bit has an effect on the tensile forces in the side reins and hence on the forces exerted on the mouth of the horse.

Ethical Animal Research

This study was approved by the local ethics commission. Sources of funding: University of Veterinary Medicine of Vienna. Competing interests: none.
The Effect of Perineural Anesthesia and Handler Position on Limb Loading and Hoof Balance of the Vertical Ground Reaction Force in Sound Horses
Authors: Van de Water E , Oosterlinck M , Willekens S , Pille F
Published: June 2014

Introduction

To facilitate interpretation of limb loading and hoof balance obtained by pressure plate analysis in lame horses, the effects of handler position and perineural anesthesia in sound horses need investigation.

Methods

Six sound Warmblood horses were walked and trotted over a pressure plate, with the handler at the left and subsequently the right side, and before and after a bilateral palmar digital nerve block. One week later, this procedure was repeated before and after a bilateral abaxial sesamoid nerve block. Peak vertical force (PVF), vertical impulse (VI) and stance time (ST) of 5 hoof prints of both forelimbs were obtained (126 Hz). Asymmetry ratios were calculated.

Toe‐heel and medio‐lateral hoof balance curves of the vertical force were calculated. Mixed model ANOVA was used for statistical analysis of asymmetry ratios (α = 0.05). Hoof balance curves were assessed qualitatively.

Results

There were no significant effects of handler position and perineural anesthesia on PVF and VI; small but significant effects of perineural anesthesia on ST at walk were associated with variability in horses′ speed between sessions at walk (P = 0.046); no significant differences at trot. Hoof balance curves were not affected by handler position or perineural anesthesia, and were highly repeatable within each individual horse.

Conclusions

The lack of any effect of handler position or perineural anaesthesia on limb loading and toe‐heel and medial‐lateral hoof balance in sound horses makes it probable that significant aberrations found using pressure plate analysis are related to abnormalities and hence may be relevant in lameness diagnosis.

Ethical Animal Research

The study was approved by the ethical committee of the Faculty of Veterinary Medicine of Ghent University (n° 2012/151). Sources of funding: Ghent University. Competing interests: none.
Internal Foot Kinematics Using High‐Speed Fluoroscopy
Authors: Weller R , Bryars J , Roach J , Pfau T
Published: June 2014

Introduction

The navicular bone (NB) and the deep digital flexor tendon (DDFT) are common sites of lameness. Greater knowledge of foot mechanics will aid in understanding of the aetiopathogenesis and may provide new opportunities for treatment and prevention. It was hypothesised that changes in the distal interphalangeal joint (DIPj) and movement of the NB and DDFT during the stance phase will lead to changes in the moment arm of the DDFT around the DIPj.

Methods

Internal hoof kinematics were determined using a high‐speed fluoroscopy system. Six horses were walked and trotted over a raised platform consisting of four force plates, through the field of view of the fluoroscopy system. The angles of the DIPj and the DDFT around the navicular bone and the moment arm of the DDFT were measured. Changes in these parameters during stance and differences between strides, gaits and horses were assessed using an ANOVA or paired T‐test as appropriate (P<0.05).

Results

The range of motion (ROM, mean ± SD) during stance of the DIPJ was 28.6 ± 4.6° (walk) and 26.5 ± 6.3 (trot) with significant differences between gaits, strides and horses (P<0.001). The angle change of the DDFT around the NB was 21.9 ± 6.0° in walk and 26.6 ± 6.5 in trot. The change in moment arm of the DDFT around the DIPj was 3.7 ± 1.3 mm in walk and 4.1 ± 2.2 mm in trot. There were no significant differences between the different time points during stance or between gaits.

Conclusions

High‐speed fluoroscopy is a novel method that allows assessment of internal foot kinematics. The observed changes between gaits during stance may result in altered stress distribution in the DDFT. Further studies will evaluate the effect of farriery intervention on internal foot kinematics.

Ethical Animal Research

this study was approved by the authors′ institution's ethics and welfare committee. Sources of funding: Royal Veterinary College. Competing interests: none.
Comparison of Cumulative Effects of Four Days of Alternate or Continuous Training on Expression of Selected Mitochondrial Genes in Rat Skeletal Muscle
Authors: Davie A , Yao M , Wang Y , Huang L , Zhou S
Published: June 2014

Introduction

Adaptations to training include the accumulation of specific proteins. The ideal stimulus that alters gene transcriptive response that initiates changes in protein concentration is important for adaptations.

Methods

Fifty‐four male Sprague‐Dawley rats were randomly divided into 9 experimental groups, with six rats in each group. The groups consisted of: control (group 1); one day of training (2); continuous training groups who trained for a further two to four days followed by three days recovery (3,4,5,6); alternate‐day training consisting of a further two to four sessions (7,8,9) finishing on the 7th day. On each training day, the animals ran on a motor driven treadmill at a slope of 10° and a speed of 19.3 m/min (∼76%VO2max) for 90 minutes. Gastrocnemius muscle specimens were obtained from the respective groups 1 hour after training ceased. Real‐time PCR was performed to determine the changes (in fold) in mRNA of PGC1α, COXIV, CaMKIV, NRF1, AMPKα1 and α2, and mtTFA. One‐way ANOVA was used in comparisons of the mean values between groups.

Results

The results showed that mRNA expression was significantly different between the training groups for AMPkα1 after the 3rd training session, PGC1α after the 4th training session, with CaMKIV significantly different following three days of recovery. COXIV and mtTFA were not significantly different at any point.

Conclusions

Training design has differing effects on expression of the selected genes. This data has provided insight into the importance of training design and recovery intervals which warrants a need for further research.

Ethical Animal Research

The study was approved by the Southern Cross University Animal Care and Ethics Committee. Sources of funding: None declared. Competing interests: none.
Muscle Fibre Type Distribution of the Thoracolumbar and Hindlimb Regions of Horses: Relating Fibre Type and Functional Role
Authors: Hyytiäinen H , Mykkänen A , Hielm‐Björkman A , Stubbs N , McGowan C
Published: June 2014

Introduction

The muscle fibre type (MFT) of the deep epaxial musculature has not been determined in horses. The objective was to determine the MFT distribution in selected muscles of thoracolumbar and hindlimb region of horses. This included deep epaxial and hypaxial muscles that were hypothesised to have a postural stabilising role. A second objective was to examine differences in MFT distribution between Arabians and Quarter horses.

Methods

Muscle biopsy samples (114) were obtained from 5 Quarter horses, 4 Arabians, and 2 Thoroughbreds. The myosin heavy chain distribution was determined by gel electrophoresis. Mann‐Whitney rank test was used to compare the proportional MFT content and differences between breeds.

Results

Mm. sacrocaudalis dorsalis medialis and diaphragm had the highest proportion of MFT‐I, 84.1% (±18.4) and 72.4% (±12.5), respectively. The remaining deep epaxial muscles and the hypaxial m. psoas minor had approximately equal MFT‐I and II proportions. Mm. psoas major, iliocostalis, longissimus dorsi and the hind limb muscles contained mostly MFT‐IIX: from 50.5% (±12.8) to 67.9% (±7.3). Quarter horses had significantly more MFT‐IIX in m. psoas major 60.8% (±9.1) than Arabians 41.9% (±3.2). Arabians had significantly more MFT‐I fibres in m. longissimus dorsi 16.9% (±4.6) than Quarter horses 9.9% (±1.4) (P<0.05).

Conclusions

The MFT distribution of the deep epaxial muscles, mm. psoas minor and diaphragm, suggest a postural stabilizing role in contrast to the fibre type proportions of the hindlimb muscles. The findings can direct diagnosis, prevention and treatment of muscular or neuromotor dysfunction in the thoracolumbar and hind limb area.

Ethical Animal Research

The study was approved by the University of Queensland Animal Ethics Committee. Explicit owner informed consent for participation in this study is not stated. Sources of funding: none. Competing interests: none.
Intra‐Operator and Inter‐Operator Reliability and Repeatability of Muscle Measurement Via Ultrasonography in the Equine Cervical Spine
Authors: Rombach N , Stubbs N
Published: June 2014

Introduction

Ultrasonography is used for functional assessment of deep peri‐vertebral muscles in people with neck pain. This study evaluated intra‐operator and inter‐operator reliability and repeatability of ultrasound image acquisition (US) and muscle cross‐sectional area measurement (CSA) of m. multifidus and m. longus colli in the equine cervical spine.

Methods

Two US operators independently acquired 60 unilateral US images per horse from 5 standing horses (mean ± SD: age: 12.1 ± 10.5 years) at spinal levels C3‐C6 (m. multifidus) and C2‐C5 (m. longus colli). Each operator traced each image blindly three times (n = 360 per operator) to calculate CSA. ANOVA analysis compared CSA across all subjects within and between operators for effects of vertebral level, reliability of image acquisition and repeatability of CSA calculation.

Results

Intra‐operator results for m. multifidus were 72% (ICC) and 5% (CV), and 90% (ICC) and 4% (CV) between operators. Image acquisition was unreliable at C6. Intra‐operator results for m. longus colli were 100% (ICC) and 0% (CV), and 77% (ICC) and 0% (CV) between operators. Image acquisition was unreliable at C2. CSA for both muscles was largest at C4 and C5.

Conclusions

Ultrasonography could be used reliably and repeatably for CSA measurement of m. multifidus and m. longus colli in the mid‐cervical spine of the horse. Further studies will determine reliability across time and CSA side‐side symmetry in horses with neck pain.

Ethical Animal Research

Approval for this study was obtained under Institutional Animal Care and Use Committee number 02‐11/020‐00. Sources of funding: Michigan State University CVM Endowed Research Funds. Competing interests: none.
Training of Horses Used for Show Jumping and its Effect on VLa4
Authors: Munk R , Hedegaard L , Möller S , Lindner A
Published: June 2014

Introduction

There are few data on training horses used for show jumping (SJ) in practice. This study presents such data and relates it to changes of VLa4 during an outdoors season (VLa4 = speed at which a blood lactate concentration of 4 mmol/l is achieved).

Methods

The training of 19 SJ (11 managed by professional trainer, PSJ, and 8 by amateur riders, ASJ) was documented and related to changes of VLa4. All horses were submitted to 3 standardized exercise tests (SET) to calculate VLa4: April/May, June/July, September: SET1, SET2, SET3. Noted daily were: Minutes of turn‐out on pasture, of walking in horse‐walker, of lungeing and of specific exercise (gymnastics, jumping and others). Data were analyzed by repeated measures ANOVA (Fisher's test as applicable) or linear regression.

Results

The duration of the specific exercises ranged between 30–60 minutes. PSJ were exercised less often and duration of each specific exercise was lower than for ASJ (P = 0.01). Considering all horses, the VLa4 increased between SET1 and SET2 when the duration of exercise and gymnastics was longer and the number of days on pasture higher (P<0.05 both). These relationships became not significant when groups were analysed separately. The VLa4 of ASJ increased between SET2 and SET3 when horses were kept on pasture for more time (P<0.05, r2 = 0.64). The VLa4 of PSJ tended to increase with a higher percentage of jumping days between SET1 and SET2 (P = 0.08, r2 = 0.30), and with longer duration of jumping exercise sessions between SET2 and SET3 (P = 0.06; r2 = 0.33).

Conclusions

The information may help to improve the training of show jumpers.

Ethical Animal Research

Horse owners gave consent for these procedures within a veterinary monitoring system. Sources of funding: none declared. Competing interests: none.
The Relationship Between Blood Lactate, Serum Muscle Enzymes, Jumping Performance and Muscle Soreness in Show‐Jumping Horses
Authors: Roberts C , Harris P , Murray R , Cnockaert R , Roberts C
Published: June 2014

Introduction

There is relatively little information concerning physiological factors affecting show‐jumping performance. This study examined the relationship between show‐jumping exercise, muscle soreness, serum muscle enzyme activity and blood lactate concentration.

Methods

Ten mixed breed horses (9.1 ± 1.9 yrs) were assessed at a British Equestrian Federation (BEF) World Class Performance three‐day training session. Riders received coaching during warm‐up and after jumping a 15 fence course (1.35–1.45 m) once on day one and twice on day two; on day three the second round was an 8 fence jump‐off. Veterinary and physiotherapy assessments of muscle soreness were performed daily before and after exercise. An international coach graded jumping technique. Blood was obtained before and on two occasions after jumping (1 minute, two hours) for measurement of serum CK and AST, and blood lactate concentration. Data were analysed using regression procedures or Spearman correlation, and Wilcoxon signed‐rank test (P<0.05).

Results

Blood lactate significantly increased one minute after jumping on all three days (P = 0.003 for all). When two rounds were jumped, lactate was significantly lower after the second round compared to the first (P = 0.006, P = 0.014). There was a positive correlation between blood lactate one minute after jumping and number of faults scored daily and overall (R2 = 0.61; P<0.01), decreased jumping technique grade (R2 = 0.69; P<0.01) and increased gluteal muscle soreness on day two (r = 0.75; P = 0.012). Plasma CK activity one minute, and 2 hours after jumping was significantly higher than before jumping on all days (P<0.01).

Conclusions

Horses with higher blood lactate concentrations after jumping demonstrated decreased jumping performance and were more likely to display muscle soreness.

Ethical Animal Research

Explicit owner informed consent for participation in this study is not stated. Sources of funding: The World Class Development Programme is funded by the Department for Culture, Media and Sport, through Exchequer and National Lottery funds, via UK Sport. Competing interests: none.
Effects of Age and Exercise Training on Oxidation of Skeletal Muscle and Blood in Mature and Yearling Horses
Authors: Smarsh D , Williams C
Published: June 2014

Introduction

The objective of this study was to determine if yearlings would have higher oxidative stress and lower antioxidant status than mature mares after a single bout of intense exercise before and after training.

Methods

Seven Standardbred yearling fillies (18 ± 2.4 mo) and seven mares (13 ± 2.1 yr) ran a repeated sprints exercise test before (RSET1) and after (RSET2) an 8‐wk training protocol. Blood samples and middle gluteal muscle samples were taken before and after exercise, and throughout recovery. Data is presented as mean ± SE and all analyses were done in the context of a linear mixed model with random intercepts for horse.

Results

In RSET1, mares had higher plasma malondialdehyde than the yearlings (P<0.05), but the yearlings had higher muscle malondialdehyde, nitric oxide, glutathione and glutathione peroxidase, erythrocyte total glutathione and glutathione peroxidase (P<0.05). In RSET2, yearlings had higher plasma nitric oxide than the mares (P<0.05). In RSET2, the mares had lower plasma malondialdehyde, and higher muscle malondialdehyde, total glutathione and nitric oxide as compared to RSET1 (P<0.05). The yearlings in RSET2 had higher muscle nitric oxide and lower erythrocyte glutathione peroxidase than in RSET1 (P<0.05). Plasma cortisol, creatine kinase and muscle glutathione peroxidase had little difference with age or training.

Conclusions

Prior to training, the yearlings had lower lipid peroxidation and higher antioxidants than the mares. Training reduced oxidative stress and improved antioxidant status in the mares, while few effects of training were seen in the yearlings. This suggests that age is an important defense against exercise‐induced oxidative stress.

Ethical Animal Research

Rutgers University Institutional Animal Care and Use Review Board approved the study. Sources of funding: none. Competing interests: none.
Innate Variability in Voluntary Drinking in Arabian Horses during Endurance Exercise
Authors: Butudom P , Spooner H , Duesterdiek‐Zellmer K , Harris P , Schott II H
Published: June 2014

Introduction

Human athletes have been characterized as either ‘good drinkers’ or ‘poor drinkers’ on the basis of voluntary water intake during and after endurance exercise. Similarly, riders of endurance horses have described some horses to be better drinkers than others; however, there are no data in horses to substantiate these claims.

Methods

Voluntary fluid intake (FI) by twenty four 2‐year‐old Arabian horses that performed 45–60 km of treadmill exercise in four experiments was recorded. All horses were raised similarly and had no training except a 12 week conditioning period before each experiment. Mean FI intake (each horse performed three or four exercise tests in each experiment) was subjected to cluster analysis to separate horses into poor, average, and excellent drinking groups. FI was also correlated to body weight (BW) loss at the end of the exercise test.

Results

Cluster analysis separated horses into poor drinkers (n = 10, FI 8.7 ± 0.7 liters and BW loss of 2.2 ± 0.4%); average drinkers (n = 11, FI 14.1 ± 0.6 liters and BW loss of 1.8 ± 0.2%); and excellent drinkers (n = 3, FI 24.9 ± 0.2 liters and BW loss of 0.7 ± 0.3%). FI was inversely correlated with BW loss (R values between −0.53 and −0.87 for all four experiments, P<0.01).

Conclusions

These data, in groups of young, similarly trained horses, are the first to support that there are innate differences in voluntary drinking during and after endurance exercise in this species.

Ethical Animal Research

All procedures were approved by the Animal Use Committee of Michigan State University Sources of funding: Equine Health Research Fund of the American Horse Shows Association, WALTHAM Centre for Pet Nutrition, and the Department of Large Animal Clinical Sciences, Michigan State University. Competing interests: none.
Influence of Exercise in the Occurrence of Gastric Ulcers in Horses
Authors: Ribeiro G , Silva LCLC , Belli CB , Mirian M , Fernandes WR
Published: June 2014

Introduction

The most frequently reported causes of gastric ulcers in horses are fasting, type of feed and management, and the administration of some drugs. More recently, physical exercise has also been pointed out as an important factor in the development of gastric lesions in athletic horses. The aim of this study was to evaluate whether treadmill exercise predisposes to the occurrence of gastric ulcers in horses.

Methods

Five Arabian horses were exercised on a high‐speed treadmill during twelve weeks. The animals were submitted to gastroscopy before the beginning and the end of the training period. The lesions were classified according to the method proposed by Macallister [1] that assigns scores for number and severity of injuries, with modifications to give a total score for the stomach, considering not only the presence and severity of ulcers, but also other findings as gastritis, hyperkeratosis, desquamation of the mucosa. The results obtained in the two periods were compared using the Wilcoxon test, with significance at P<0.05.

Results

In the first gastroscopy two animals had very low scores for lesion number and severity and three horses had no injury. In contrast, in the second evaluation, all animals had higher scores. A significant difference was observed between the two periods (before and after training) considering both methods of gastric lesion classification.

Conclusions

We concluded that Arabian horses exercised on a treadmill may develop gastric lesions. The possible influence of these lesions on athletic performance and other parameters should be considered by researchers who study equine exercise physiology.

Ethical Animal Research

This study was approved by the Ethics Committee on Animal Use (protocol number 1741). Sources of funding: FAPESP 2012/10886‐3. Competing interests: none.