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Equine back function is of concern to riders, as well as to veterinarians and physiotherapists; these groups may benefit from knowledge about spinal motion on the circle. This descriptive and comparative study aimed to quantify equine neck, back and pelvic motion in walk, trot and canter on a 9 m circle. Sixteen healthy horses in training, of varying breed and conformation, were measured using optical motion capture (150 Hz), with optical markers on the poll, withers, T15, tubera coxae and lumbosacral joint. Cervicothoracic and thoracolumbar flexion–extension and lateral bending, and pelvic roll, pitch and yaw, were statistically evaluated using mixed models. Motion patterns showed distinct differences between gaits, but were generally similar between horses. The thoracolumbar back was bent towards the inside of the circle (stride mean 5-6º for all gaits). The cervicothoracic spine was more flexed in walk (18°), and more extended in canter (-4—-8°), compared to trot (6–7°), whereas the thoracolumbar spine was slightly less extended in canter than in walk. Thoracolumbar flexion–extension range of motion (ROM) increased from walk (4°) to canter (9°), as did pelvic pitch ROM (walk 7° and canter 15–16°), while back lateral bending ROM and pelvic yaw ROM were lowest in trot. Taken together, the study findings suggest that neck and back motion patterns on the circle reflect an interaction between the constraints of circular movement, and the mechanics and characteristics of each gait.

Pressure from the bit in the horse's mouth, rein tension, likely feels unpleasant to the horse due to sen-sitive oral tissues. Through trial and error, the horse may learn how to adjust their behavior in order to avoid, diminish or cease uncomfortable sensations from the bit. We hypothesized that oral behaviors and head movements in response to rein tension have the function to avoid or escape the rein tension. The study objective was to assess in what way oral behaviors and head movements affect rein tension and determine the magnitude of rein tension at the onset and end of these behaviors. Twenty Warm-blood horses were fitted with a bitted bridle and subjected to 8 trials of backing up in response to a rein tension signal with the handler standing next to the horse's withers. The rein tension signal was grad-ually increased and then immediately released when the horse stepped back. A rein tension meter and video recordings were used for data collection. Linear mixed models were used for the statistical analysis. There was a decrease in mean rein tension (sum of left and right rein) from onset to end for open mouth ( P < 0.001, from 19 to 11 Newtons (N), biting on the bit ( P = 0.004, from 11 to 5 N), and head upward ( P = 0.024, from 16 to 12 N), while there was an increase in rein tension associated with head forward ( P = 0.015, from 27 to 37 N) and head downward ( P < 0.001, from 17 to 46 N). Our results suggest that horses will open their mouth, or bite on the bit, to alleviate the oral tissues from pressure; move the head upward to avoid rein tension and move the head forward or downward to increase rein tension, likely in a presumed attempt to break free from the pressure applied. The horse's oral behaviors and head movements during training can be used to gain a greater understanding of how the horse perceives the magnitude of rein tension. (c) 2022 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )

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.

As techniques for equine biomechanical research have become more accessible and affordable, the literature published in this area has exploded. Literature reviews have become more popular of late and, more specifically, several literature reviews in areas related to equine biomechanics have been published. A scoping review is a relatively new approach, where a general aim is to map the body of literature on a topic area, accounting for criteria for inclusion and exclusion. However, problems can arise both in performing the review and in critiquing the findings. In this manuscript, the authors repeat a published scoping review of equine biomechanics aiming to map 'the existing literature in the field of equine movement analysis'. The search criteria from the previous study were reviewed and the performance of the search criteria was iteratively studied to find as many relevant papers as possible. The results yielded 77% more publications than the original review mainly as a consequence of not limiting the search strategy to papers including "equine" or "horse" in the title. The importance of using appropriate and inclusive search terms is highlighted together with evaluating the findings within the context of the discipline and time frame of the review. (c) 2022 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

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

Objective To investigate whether dog and cat owners and their pets share a risk of developing diabetes. Design Cohort study. Setting Register based longitudinal study, Sweden. Participants 208 980 owner-dog pairs and 123 566 owner-cat pairs identified during a baseline assessment period (1 January 2004 to 31 December 2006). Main outcome measures Type 2 diabetes events in dog and cat owners and diabetes events in their pets, including date of diagnosis during the follow-up period (1 January 2007 to 31 December 2012). Owners with type 2 diabetes were identified by combining information from the National Patient Register, the Cause of Death Register, and the Swedish Prescribed Drug Register. Information on diabetes in the pets was extracted from veterinary care insurance data. Multi-state models were used to assess the hazard ratios with 95% confidence intervals and to adjust for possible shared risk factors, including personal and socioeconomic circumstances. Results The incidence of type 2 diabetes during follow-up was 7.7 cases per 1000 person years at risk in dog owners and 7.9 cases per 1000 person years at risk in cat owners. The incidence of diabetes in the pets was 1.3 cases per 1000 dog years at risk and 2.2 cases per 1000 cat years at risk. The crude hazard ratio for type 2 diabetes in owners of a dog with diabetes compared with owners of a dog without diabetes was 1.38 (95% confidence interval 1.10 to 1.74), with a multivariable adjusted hazard ratio of 1.32 (1.04 to 1.68). Having an owner with type 2 diabetes was associated with an increased hazard of diabetes in the dog (crude hazard ratio 1.28, 1.01 to 1.63), which was attenuated after adjusting for owner’s age, with the confidence interval crossing the null (1.11, 0.87 to 1.42). No association was found between type 2 diabetes in cat owners and diabetes in their cats (crude hazard ratio 0.99, 0.74 to 1.34, and 1.00, 0.78 to 1.28, respectively). Conclusions Data indicated that owners of a dog with diabetes were more likely to develop type 2 diabetes during follow-up than owners of a dog without diabetes. It is possible that dogs with diabetes could serve as a sentinel for shared diabetogenic health behaviours and environmental exposures.

The study investigated between-rider differences in pelvic roll and pitch motion during horseback riding as the horse walked around circles without rein contact (walk on long reins), with rein contact, and with moderate collection. Ten horses were ridden by five riders on left and right 10 m circles, in a partly crossed design, yielding 14 trials. Each trial included each of the three walk variations in both directions. Riders wore an inertial measurement unit (IMU), logging at 100 Hz, dorsally on the pelvis. Pelvic roll and pitch data were split into strides based on data from IMU-sensors on the horse's hind cannons. Data were analysed using signal decomposition into the fundamental frequency (the stride frequency) and its first two harmonics. Mixed models accounting for the type of walk were used to analyse how riders differed in roll and pitch pelvic motion in two ways: comparing amplitudes of the frequency components and comparing whole stride mean data. Graphically pelvic pitch showed substantial timing and amplitude differences between riders, and this was confirmed statistically. Pelvic roll timing was similar, but amplitude varied between the riders, both graphically and statistically. Individual rider patterns tended to persist across different horses and all exercises. These results suggest that exercises at walk can be ridden with different pelvis pitch timing, a fact that has so far not been discussed in the equestrian literature. Whether pelvic pitch timing affects the horse's performance remains to be investigated.

Simple Summary The reins are used to control speed and direction of the horse’s movement through the application of tension by the rider. When the rider holds the reins with a constant light contact, the mechanics of each gait is associated with a cyclic pattern of head and neck movements that is revealed in rein tension oscillations that have a typical shape and repetition frequency in each gait. The effects of the rider’s aids, rider imbalance and extraneous movements of the horse’s head and neck are superimposed on the basic patterns of the gaits. Rein tension is of interest to scientists and horsemen alike. Tension is relatively easy to measure but the equipment, analytic techniques and reporting of rein tension vary greatly. This paper makes recommendations to guide the selection of suitable equipment and appropriate methods for the collection, analysis and reporting of rein tension data. The goals are to describe correct procedures and common pitfalls in the collection, analysis and reporting of rein tension data that will facilitate comparisons between different studies. Abstract Rein tension is relatively easy to measure, and the resulting data are useful for evaluating the interaction between horse and rider. To date, there have been a number of studies using different transducers, calibration methods and analytical techniques. The purpose of this paper is to make recommendations regarding the collection, analysis and reporting of rein tension data. The goal is to assist users in selecting appropriate equipment, choosing verified methods of calibration, data collection and analysis, and reporting their results consistently to facilitate comparisons between different studies. Sensors should have a suitable range and resolution together with a fast enough dynamic response, according to the gait, speed and type of riding for which they will be used. An appropriate calibration procedure is necessary before each recording session. A recording frequency of 50 Hz is adequate for most rein tension studies. The data may be analyzed using time-series methods or by extracting and analyzing discrete variables chosen in accordance with the study objectives. Consistent reporting facilitates comparisons between studies.

Many breeding organisations include a subjective scoring of rideability by a professional rider into their evaluation of sports horses, but the consistency and reliability of the scoring system is debateable. The aim of this study was to investigate (i) whether professional riders agree in their scoring of rideability, and (ii) whether rideability scores are affected by rein tension, horse conflict behaviour, heart rate, and salivary cortisol, and (iii) whether riders induce different levels of conflict behaviour and physiological responses in the horses. Ten professional, female riders each rode 10 dressage horses (level M German scale; n = 100 combinations) through a standardised dressage test (10 min warm-up followed by a 4-min test) and subsequently scored the horses for rideability on the official 1–10 scale (1 = poor to 10 = excellent) from the Danish Riding Federation. Rein tension, horse heart rate, saliva cortisol and conflict behaviour were measured for each rider-horse pair. The riders were inconsistent in their scoring of rideability to the individual horses, e.g. scores for one of the horses ranged from 1 to 8. There was a significant effect of rider (P = 0.003) and the frequency of conflict behaviour (undesired head movements: P

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.

Rein tension signals are, in essence, pressures applied on the horse's mouth or nose, via the bit/noseband, by a rider or trainer. These pressures may feel uncomfortable or even painful to the horse and therefore it is important to reduce rein tension magnitude to a minimum. The aim of this study was to investigate the magnitude of a rein tension signal for backing up, using negative reinforcement. We wanted to assess how much the magnitude of rein tension could be reduced over eight trials and if the learning process would differ depending on headstall (bridle/halter). Twenty Warmblood horses were trained to step back from a rein tension signal with the handler standing next to the horse, holding the hands above the horse's withers. As soon as the horses stepped back, rein tension was released. The horses were either trained with a bridle first (first treatment, eight trials) and then with a halter (second treatment, eight trials), or vice versa in a cross-over design. All horses wore a rein tension meter and behavior was recorded from video. The sum of left and right maximum rein tension from onset of the rein tension signal to onset of backing (signaling rein tension) was determined for each trial. Mixed linear and logistic regression models were used for the data analysis. In both treatments, signaling rein tension was significantly lower in trial 7-8 than the first trial (p < 0.02). Likewise, signaling rein tension was significantly lower (p < 0.01), and the horses responded significantly faster, (p < 0.001) in the second treatment compared to the first, regardless of headstall. The maximum rein tension was reduced from 35 N to 17 N for bridle (sum of left and right rein) and from 25 N to 15 N for halter in the first eight trials. Rein tension was then further reduced to 10 N for both bridle and halter over the eight additional trials in the second treatment, i.e. to approximately 5 N in each rein. There was no significant difference in learning performance depending on headstall, but the bitted bridle was associated with significantly more head/neck/mouth behaviors. These results suggest that it is possible to reduce maximum rein tension by half in just eight trials. The findings demonstrate how quickly the horse can be taught to respond to progressively lower magnitudes of rein tension through the correct application of negative reinforcement, suggesting possibilities for substantial improvement of equine welfare during training.

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.

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.

Background: Dog ownership is associated with increased physical activity levels and increased social support, both of which could improve the outcome after a major cardiovascular event. Dog ownership may be particularly important in single-occupancy households where ownership provides substitutive companionship and motivation for physical activity. Methods and Results: We used the Swedish National Patient Register to identify all patients aged 40 to 85 presenting with an acute myocardial infarction (n=181 696; 5.7% dog ownership) or ischemic stroke (n=154 617; 4.8% dog ownership) between January 1, 2001 and December 31, 2012. Individual information was linked across registers for cause of death, sociodemographic, and dog ownership data. We evaluated all-cause mortality and risk of recurrent hospitalization for the same cause until December 31, 2012. Models were adjusted for socioeconomic, health, and demographic factors at study inclusion such as age, marital status, the presence of children in the home, area of residence, and income, as well as all registered comorbidities and hospitalization for cardiovascular disease in the past 5 years. Dog owners had a lower risk of death after hospitalization for acute myocardial infarction during the full follow-up period of 804 137 person-years, with an adjusted hazard ratio (HR) of 0.67 (95% CI, 0.61 to 0.75) for those who lived alone, and HR of 0.85 (95% CI, 0.80 to 0.90) for those living with a partner or a child. Similarly, after an ischemic stroke, dog owners were at lower risk of death during the full follow-up of 638 219 person-years adjusted HR of 0.73 (95% CI, 0.66 to 0.80) for those who lived alone and HR of 0.88 (95% CI, 0.83 to 0.93) for those living with a partner or a child. We further found an association of dog ownership with reduced risk of hospitalization for recurrent myocardial infarction (HR, 0.93; 95% CI, 0.87 to 0.99). Conclusions: We found evidence of an association of dog ownership with a better outcome after a major cardiovascular event. Although our models are adjusted for many potential confounders, there are also unmeasured confounders such as smoking that prevent us from drawing conclusions regarding a possible causal effect.

Objectives The aim of this study was to describe the incidence of feline dystocia with respect to breed. Methods The data used were reimbursed claims for veterinary care insurance and/or life insurance claims in cats registered in a Swedish insurance database from 1999–2006. Results The incidence rates for dystocia were about 22 cats per 10,000 cat-years at risk, 67 per 10,000 for purebred cats and seven per 10,000 for domestic shorthair cats. The median age was 2.5 years. A significant effect of breed was seen. An incidence rate ratio (IRR) that was significantly higher compared with other purebred cats was seen in the British Shorthair (IRR 2.5), the Oriental group (IRR 2.2), Birman (IRR 1.7), Ragdoll (IRR 1.5) and the Abyssinian group (IRR 1.5). A significantly lower IRR was seen in the Norwegian Forest Cat (IRR 0.38), the Maine Coon (IRR 0.48), the Persian/Exotic group (IRR 0.49) and the Cornish Rex (IRR 0.50). No common factor among the high-risk breeds explained their high risk for dystocia. There was no effect of location; that is, the incidence rate did not differ depending on whether the cat lived in an urban or rural area. Caesarean section was performed in 56% of the cats with dystocia, and the case fatality was 2%. Conclusions and relevance The incidence rate for dystocia was of a similar magnitude in purebred cats as in dogs. The IRR varied significantly among breeds, and the main cause for dystocia should be identified separately for each breed. A selection for easy parturitions in breeding programmes is suggested.

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 0.05 P >0.001, but significant if P P 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.

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.

The symmetry of the rider is highly relevant, and in the equestrian community it is generally thought that a symmetrical rider has a better possibility to influence the horse in an optimal way. The aim of the study was to analyse and compare frontal plane kinematics of the core body segments in ten riders while riding and while rocking a balance chair from side-to-side. It was hypothesized that the riders were asymmetrical in relation to their intersegmental strategies when comparing between left and right directions and that individual riders would display the same postural strategies when riding and when rocking the balance chair. Ten moderately-skilled riders wore a full-body marker set that was tracked by a motion capture system as they rocked a balance chair from side to side. Inertial measurement units attached to the head, trunk and pelvis were used to measure the segmental movements while riding in left and right directions. Roll rotation data for head, trunk and pelvis were averaged over available strides/cycles. Results from mixed models showed that the riders were asymmetric when comparing riding in left vs right directions, for example the trunk was rotated 19° to the right on the right circle and 14° to the left on the left circle, on average. Riders adopted the same asymmetrical posture whether they were riding in the left or right direction on straight lines, circles or leg yielding. A significant relationship was found between postural asymmetries when riding and when rocking the balance chair, one degree of pelvis or head roll asymmetry on the chair predicted 2.4 (SE 0.9) degrees of asymmetry while riding. Future studies may investigate the value of seated, off-horse postural training for improving rider symmetry and thereby equestrian performance.

Foot pronation is a common postural condition that is related to postural asymmetry, and that may affect performance in a variety of sports. The aim of this study was to evaluate whether unmounted riders (n=18) with predominantly right or left foot pronation had an increased contralateral pelvic drop during stance of the more pronated foot when walking. This was a preliminary step toward investigating the effects of foot pronation during riding. Kinematic data were collected in 3D (250 Hz) using eight motion capture cameras during walking. The amount of foot pronation was measured by summing eversion and external rotation, and it was analysed in relation to maximal pelvic drop during stance. The results showed that during walking, the majority of the riders had significantly greater contralateral pelvic drop when the foot with the higher degree of pronation was in early stance. If the demonstrated postural asymmetry carries over to other activities where weight is distributed to the feet, e.g. at riding when the riders feet exert a force against the stirrups, this may affect the rider’s performance. Further studies are needed to describe the influence of foot pronation in mounted horseback riders.

SummaryReasons for performing study Lungeing is often part of the clinical lameness examination. The difference in movement symmetry, which is a commonly employed lameness measure, has not been quantified between surfaces. Objectives To compare head and pelvic movement symmetry between surfaces and reins during lungeing. Study design Quantitative gait analysis in 23 horses considered sound by their owners. Methods Twenty-three horses were assessed in-hand and on the lunge on both reins on hard and soft surfaces with inertial sensors. Seven movement symmetry parameters were quantified and used to establish 2 groups, namely symmetrical (n = 9) and forelimb-lame horses (n = 14), based on values from straight-line assessment. Movement symmetry values for left rein measurements were side corrected to allow comparison of the amount of movement symmetry between reins. A mixed model (P0.073). No significant influence of surface or rein was identified for any of the pelvic movement symmetry measures in either group. Conclusions While more symmetrical horses showed a consistent amount of movement symmetry across surfaces/reins, horses objectively quantified as lame on the straight showed decreased movement symmetry during lungeing, in particular with the lame limb on the inside of a hard circle. The variation within group questions straight-line movement symmetry as a sole measure of lameness without quantification of movement symmetry on the lunge, ideally on hard and soft surfaces to evaluate differences between reins and surfaces. In future, thresholds for lungeing need to be determined using simultaneous visual and objective assessment.

Pyometra is a clinically relevant problem in intact female cats and dogs. The etiology is similar in both animal species, with the disease caused by bacterial infection of a progesterone-sensitized uterus. Here, we studied pyometra in cats with the aim to describe the incidence and probability of developing pyometra based on age and breed. The data used were reimbursed claims for veterinary care insurance or life insurance claims or both in cats insured in a Swedish insurance database from 1999 to 2006. The mean incidence rate (IR) for pyometra was about 17 cats per 10,000 cat years at risk (CYAR). Cats with pyometra were diagnosed at a median age of 4 years and a significant breed effect was observed. The breed with the highest IR (433 cats per 10,000 CYAR) was the Sphynx, and other breeds with IR over 60 cats per 10,000 CYAR were Siberian cat, Ocicat, Korat, Siamese, Ragdoll, Maine coon, and Bengal. Pyometra was more commonly diagnosed with increasing age, with a marked increase in cats older than 7 years. The mean case fatality rate in all cats was 5.7%, which is slightly higher than corresponding reports in dogs of 3% to 4%. Geographical location (urban or rural) did not affect the risk of developing the disease. The present study provides information of incidence and probability of developing pyometra based on age, breed, and urban or rural geographical location. These data may be useful for designing cat breeding programs in high-risk breeds and for future studies of the genetic background of the disease.

Canine epilepsy is one of the most common neurological conditions in dogs but the actual incidence of the disease remains unknown. A Swedish animal insurance database has previously been shown useful for the study of disease occurrence in companion animals. The dogs insured by this company represent a unique population for epidemiological studies, because they are representative of the general dog population in Sweden and are followed throughout their life allowing studies of disease incidence to be performed. The database covers 50% of all insured dogs (in the year 2012) which represents 40% of the national dog population. Most commonly, dogs are covered by both veterinary care insurance and life insurance. Previous studies have shown that the general data quality is good, but the validity of a specific diagnosis should be examined carefully before using the database for incidence calculations. The aim of the current study was therefore to validate the information contained in the insurance database regarding canine epilepsy. The validation focused on the positive predictive value and the data-transfer from the veterinary practice records to the insurance database. The positive predictive value was defined as the proportion of recorded cases that actually had the disease in question. The quality of the data-transfer was assessed by comparing the diagnostic codes in practice records to the codes in the insurance database. The positive predictive value of the diagnostic codes for canine epilepsy (combining “epileptic convulsions” and “idiopathic epilepsy”) in the insurance database was validated in a cross-sectional study where insurance claims for canine epilepsy were compared to diagnostic information in practice records. A random sample of dogs with a reimbursed insurance claim during 2006 was included in the study sample ( n = 235). Practice records were requested by mail from attending veterinarians. Two independent examiners scrutinized all the records. All 235 dogs were coded correctly in the database as they really had suffered seizures with or without convulsions, and the quality of the data-transfer was therefore excellent. In total, 167 dogs (71%) were classified as cases of canine epilepsy according to pre-defined criteria, and the positive predictive value was therefore considered relatively high. Based on these results, it was concluded that the data regarding canine epilepsy in the insurance database can be used for further population studies.

Health in horses is thought to be influenced by conformation traits, including limb deviations. As few studies on the subject are available, the relevance of selecting for specific conformation traits to improve health is uncertain. The objective was to determine the genetic variation in conformation and relationships between conformation and health status in young riding horses. Analyses included 8187 young horses independently examined for conformation and health, during the Swedish Riding Horse Quality Test (RHQT) for 4–5 year-old horses. Both descriptive conformation traits and assessment scores of conformation were studied. Phenotypic effects were estimated using single trait General Linear Models and heritabilities and genetic correlations using multi-trait linear animal models. Four major health indicators were constructed from the detailed veterinary examinations. Conformation assessment scores were all favourably related to at least one of 4 studied health traits, both phenotypically and genetically. Genetic correlations reached 0.75 between conformation scores for head-neck-body and locomotion examinations, including flexion tests, and 0.43 for limb scores and locomotion examinations. Best health status was found for an intermediate-sized horse, with a well-positioned neck, a light front, and no major limb deviations. This finding was consistent with the role of correct movements at trot. Among limb deviations stiff pasterns, toed-out or toed-in forelimbs, and small or large hock angles showed highest negative effects on health. However, the prevalence of limb deviations was generally low, thus only toed-in forelimbs and small joints had significant genetic correlations to impaired health. Heritabilities for withers height, cannon bone circumference and overall conformation scores (except for limbs), were medium to high (0.20–0.67, s.e. 0.03–0.04). For specific limb deviations, heritabilities were in the range of 0.01–0.15 (s.e. 0.01–0.02) on the observed scale, corresponding to 0.04–0.48 on the underlying quantitative scale. Heritabilities of conformation traits and favourable correlations to health indicate good opportunities for genetic improvement of conformation, and indirectly to some extent also of health. However, only limited improvements could be expected for the prevalence of some limb deviations, where frequencies are already low.

The basis for all observational studies is the availability of appropriate data of high quality. Data may be collected specifically for the research purpose in question (so-called "primary data"), but data collected for other purposes (so-called "secondary data") are also sometimes used and useful in research. High accuracy and precision are required (irrespective of the source of the data) to arrive at correct and unbiased results efficiently. Both careful planning prior to the start of the data acquisition and thorough procedures for data entry are obvious prerequisites to achieve high-quality data. However, data should also be subjected to a thorough validation after the collection. Primary data are mainly validated through proper screening, by using various descriptive statistical methods. Validation of secondary data is associated with specific conditions - the first of which is to be aware of the limitations in its usefulness imposed by procedures during collection. Approaches for validation of secondary data will be briefly discussed in the paper, and include patient chart review, combining with data from other sources, two-stage sampling, and aggregated methods.

The aim of this study was to investigate the behavioural response of horses to rein contact and the movement of the riders' hands through analysis of data from horses ridden at two different head and neck positions. It was hypothesised that the riders' hand movements and rein tension would generate behavioural responses from horses and that these responses would be more marked when horses were ridden 'on the bit' than when unrestrained. Data were collected from seven dressage horse/rider combinations at sitting trot on a high speed treadmill. Kinematics were recorded using a 12-camera, infrared-based opto-electronic system. Three horses wore a rein tension meter. Behavioural registrations were made from video. Behavioural responses included lip movement, mouth movement, open mouth, change in ear position, head tilt and tail movement. Mouth movements were associated with the suspension phase of the trot. 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 were related to mouth movements. Interactions between horses and riders are complex and highly variable.

†‡ § # ¶ Summary Reasons for performing study: Training regimens of showjumping horses under field conditions are largely undocumented. Objectives: The aims of this study were to quantify and compare training regimens used in professional-level showjumping yards, with respect to time exercised and type of activity. Study design: Prospective cohort study. Methods: A prospective 6-month cohort study of showjumping horses in 4 European countries (The Netherlands, Sweden, Switzerland, Great Britain) was designed to analyse training and health data, in yards with several horses in training and riders competing at professional level. Riders documented the daily frequency and duration of all physical activities of the horses. Variation in training routines were compared between riders, location and time. Mixed-models analysis was used to examine factors associated with total time exercised and time spent in flatwork. Results: In 4 countries, the 31 participating riders trained 263 European Warmbloods. The total days at risk (e.g. days in which the horses were considered fit for exercise) was 39,262. Mean time spent in daily exercise, including ridden work, lungeing and treadmill exercise, varied between riders from 19–52 min/day at risk. There was considerable variation in activities and level of heavy work and light exercise, i.e. turnout. Total time exercised and time spent in flatwork differed with month, country and proportion of days lost to training. Low variation of activities was associated with decreased total time trained and increased time spent in flatwork. Conclusions: Riders at this elite professional level of showjumping used training regimens that vary substantially in time spent training and other physical activities and showjumping horses are challenged differently during training despite competing at the same level. Whether all training regimens prepare the horses equally for the demands of competition remains to be determined.

Dogs enrolled in a Swedish insurance company (during 1995-2006) were studied for development of pyometra and mammary tumours (MTs), with special attention to breed and age. There were over 260,000 female dogs with over 1,000,000 dog-years at risk (DYAR) in the database, using data on bitches up to 10 years of age and 110 breeds with over 1000 DYAR. In total, 20 423 bitches were diagnosed with pyometra and 11,758 with MTs and 30,131 with either or both of the two diseases. The incidence rate (IR) for pyometra was 199 (95% CI 196-202), for MTs 112 (95% CI 110-114) and for either or both of the two diseases 297 (95% CI 294-301) dogs per 10,000 DYAR. The mean age of diagnosis pyometra was 7.0 years (SD ± 2.2), MTs 8.0 years (SD ± 1.6). In all breeds, the overall proportion of the bitches that developed disease by 10 years of age was for pyometra 19%, MTs 13%, and either or both of two diseases 30%. The top 10 breeds diagnosed with either or both of the two diseases were the Leonberger (73%), Irish Wolfhound (69%), Bernese Mountain Dog (69%), Great Dane (68%), Staffordshire Bull Terrier (66%), Rottweiler (65%), Bullterrier (62%), Doberman (62%), Bouvier des Flandres (60%), Airdaleterrier (60%). These data provide information of the combined disease incidence in a large number of different breeds. Breed variations in incidence rate suggests genetic components in disease development. Our study may be valuable in the search for genetic risk-factors or protective factors.

Summary Reasons for performing study Acquired equine polyneuropathy (AEP, also known as ‘Scandinavian knuckling syndrome’), is a serious disease of unknown aetiology, which emerged clustering in horse farms in Sweden, Norway and Finland in the 1990s. Clinical and epidemiological data regarding the syndrome are scarce. Objectives To describe the clinical and epidemiological findings and outcome in outbreaks of AEP and compare risk factors in affected and unaffected horses on affected farms in Norway and Sweden during 2007–2009. Methods Neurological examinations were performed and data collected regarding demography, usage, turning-out, feeding, prophylactic strategies and long-term outcome. Results Thirteen affected farms with 157 horses of various breeds, of which 42 were AEP cases, were studied. Typical digital extensor dysfunction and knuckling of pelvic limbs were noted in 34 definitive cases. Eight additional plausible cases had a severe, acute course of neurological disease. There were no signs of brain or cranial nerve dysfunction. Cases occurred from December to April, with new cases emerging within 100 days of the index case. Affected and unaffected horses were fed wrapped forage. Prevalence for AEP was 27% and case fatality 29%. The median duration of AEP in survivors was 4.4 months (1–17 months). Survivors returned to full work within 19 months (median 6.6 months). Acquired equine polyneuropathy was less prevalent in horses aged >12 years and young horses had a higher chance of survival than older horses. Management factors did not differ between affected and unaffected horses. Conclusions Acquired equine polyneuropathy is a potentially fatal neurological disease characterised by pelvic limb knuckling. Surviving horses returned to normal function after a long period of rest. Cases were clustered in farms during the winter/spring season. Wrapped forage was used in all farms. Potential relevance The results provide valuable insights into the clinical examination, handling and prognosis of cases of AEP, an emerging neurological disease of unknown aetiology in horses.

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 1 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 (1 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.

Summary Reasons for performing study: Disturbances in skeletal development, primarily osteochondrosis (OC) and palmar/plantar osseous fragments (POF), have been commonly reported as problems in young horses. However, there are few reports of such findings for epidemiological analyses or breeding purposes. Objectives: To evaluate equine hospital data as a possible source of information for genetic evaluations by estimating prevalence and heritability of OC in the stifle, hock and fetlock joints and of POF in the fetlock. Methods: Data on Swedish Warmblood (SWB) horses were obtained from a large equine hospital in south Sweden. Prevalences were based on radiographic examinations of 879 screened horses, mainly evaluated as part of a prepurchase examination and 3639 horses with a reported history of orthopaedic problems. For the heritability study the 2 data sources were pooled and 3199 examined horses with pedigree information were considered for the linear animal model analyses. Results: The overall prevalence of OC was 13% (stifle 9%, hock 6% and dorsal osseous fragments in fetlock [DOF] 10%) and POF 10%. The overall heritability of OC was 0.05 on the visible binomial scale. The corresponding heritabilities for OC in the stifle were 0.03, hock 0.08, DOF 0.10 and POF 0.13. These values correspond to heritabilities of 0.09–0.38 on the underlying quantitative scale. Conclusions and potential relevance: Obtained prevalences and heritabilities were in accordance with other studies, supporting the hypothesis that data regularly obtained from equine hospitals may be a valuable source in studies of inherited disorders such as OC and POF. There is a need for more standardised documentation of diagnoses and consistent recording of identity of examined horses using passports or breed databases. Compilation of results from major clinics is desired in order to cover most progenies of stallions used in a region or nation.