Use of three‐dimensional acceleration sensing to assess dairy cow gait and the effects of hoof trimming

The aim of this study was to assess the use of three‐dimensional acceleration sensing to describe the gait of dairy cows and the effect of hoof trimming. In Trial 1, a three‐dimensional acceleration sensor was attached to the carpal region of a front leg of six Holstein cows who were then walked for 9 m. Results showed that measures of acceleration could clearly show the presence of steps, which were divided into an acceleration phase, which involved the hoof descending to and ascending from the ground, and a non‐acceleration phase, which included the swing phase. Lissajous figures could succinctly depict the degree of acceleration for each cow and showed that one cow who was lame walked with greater vertical and lateral acceleration than the remaining cows. In Trial 2, 17 loose‐housed Holstein cows were walked for 20 m during the month before, once during the month after and once 2 months after hoof trimming with the sensor attached at the end of their thoracic vertebrae to measure acceleration of the whole body. To relate the acceleration of the body to movements of the legs, image analysis was used to the range of vertical movement of four major skeletal joints, using visual markers attached to them. Hoof trimming significantly (P < 0.005) decreased both the range of vertical movement of the joints of front and hind legs and the variance of lateral and forward acceleration at the end of the thoracic vertebrae, suggesting improved gait pattern smoothness. Acceleration sensing was able to characterize variation among gait patterns of the cows and could reproduce the pattern shown by image analysis. This study demonstrates that three‐dimensional acceleration sensing of either the carpal region of a front leg or the end of the thoracic vertebrae is useful to detect walking irregularities and evaluate the effectiveness of hoof trimming on walking ability of cattle.     

The effect of hoof trimming on radiographic measurements of the front feet of normal Warmblood horses

The understanding of the normal position of the third phalanx (P3) and the distal sesamoid bone in relation to the size and shape of the hoof capsule in sound horses is helpful in the diagnosis of equine foot lameness. Some measurements on radiographs used to define the position of the pedal bone within the hoof capsule are significantly influenced by hoof trimming and the height of the withers. In this study, the front hooves of 40 Warmblood horses were radiographed twice, eight weeks apart, both before and after their hooves were trimmed by an experienced farrier. Using the software programme Metron PX, 22 parameters on the lateromedial view and 16 parameters on the dorsopalmar view were measured and the effect of hoof trimming and height of the withers were calculated, respectively. Some of the hoof parameters showed mild positive correlation with the height of the withers. In 70% of the horses the left hoof capsule and P3 were significantly larger than the right. Hoof trimming had a remarkable influence on hoof conformation, especially for parameters in the toe region. Of all the measurements that describe the position of the third phalanx (P3) in relation to the hoof capsule, the distances between the distal tip of P3 to the solar surface of the foot, P3 to the tip of the toe and P3 to the point of break-over showed the greatest differences before and after trimming. The database of the present study can be used by farriers and veterinarians as a guideline for routine and corrective shoeing of Warmblood horses.     

The effects of one-time hoof trimming on blood biochemical composition, milk yield, and milk composition in dairy cows

Although not scientifically proven, hoof trimming has been empirically shown to increase milk yields in healthy dairy cows. In this study, we examined the effect of one-time hoof trimming on blood biochemical composition, milk yield, and milk composition in healthy dairy cows. Eleven cows in the mid to late lactation period that were clinically fit and without hoof disease were subjected to hoof trimming, and metabolic profile tests and dairy herd improving tests were performed before and three weeks after the hoof trimming. The metabolic profiles showed changes in albumin, blood urea nitrogen, ammonia, glucose, and beta-hydroxybutyric acid as a result of the hoof trimming. This was indicated by the fact that the cows began to intake more roughage after hoof trimming than prior to hoof trimming, and rumen fermentation became stable. There was no change in milk yield after trimming. However, the milk fat and milk protein compositions were significantly increased after trimming.     

The Effect of Tungsten Road Nails on Upper Body Movement Asymmetry in Horses Trotting on Tarmac

Tungsten road nails are commonly used by farriers to increase grip between the hoof and the ground surface. There is limited evidence relating the use of road nails to the fundamental mechanics of movement. Grip is important for efficient deceleration on landing and subsequent propulsion, but this must be balanced against an amount of slip to divide the landing force into horizontal as well as vertical subcomponents. Here, we conducted an intervention study to quantify the effect of lateral heel road nail placement on weight bearing and propulsion in 10 horses trotting on tarmac. Wireless inertial measurement units measured vertical movement asymmetry. Differences in head and pelvic movement asymmetry before/after subsequent application of laterally placed road nails to forelimb and hindlimb hooves in a randomized order were compared to zero value (no change) with a one-sample t-test, P < .05. Left-to-right tuber coxae movement amplitude difference was significantly more negative (−3.25 mm, P = .03), suggesting more right than left tuber coxae movement amplitude, after application of a road nail to the left hindlimb. No movement asymmetries at the poll, withers, or sacrum were detected after nail placement (all P > .055). Pelvic movement indicates a very small increase in weight bearing and propulsion provided by the hindlimb with a laterally placed road nail compared to the contralateral hindlimb. Further work is needed to investigate slip- and grip-related parameters at the level of the hoof and to investigate the long-term consequences of very small changes in movement asymmetry.     

Comparison of the trimming procedure of six different farriers by quantitative evaluation of hoof radiographs

Hoof preparation and shoe fit are integral to the long term soundness and athletic ability of horses. The farrier influences the balance of the hoof by both the trimming and the shoeing procedure. The goal of this study was to investigate and quantify the influence of the farrier on hoof parameters by trimming. Forty Warmblood horses ranging in age from 6–12 years and withers height 162–172 cm were included. They were divided into six groups consisting of six or seven horses each, shod by one of six different farriers. The hoofs of the horses were radiographed twice using a standardised method before and after trimming. Measurements were taken from digitalised radiographs using a software program.Significant differences were identified between farriers for almost all parameters on the lateromedial radiographic views after two consecutive trimming procedures. Comparing the results of both trimming procedures, significant differences for several farriers were found in the lateromedial and dorsopalmar views. There were significant differences for most of the measured hoof parameters between the six farriers and between consecutive trimmings of the same farrier. The results underline the individual influence of the farrier on hoof shape and balance.     

The effect of claw trimming on the hoof health of Swedish dairy cattle

A 2-year experiment on the effect of claw trimming on hoof health was performed in 77 Swedish dairy herds (3444 dairy cattle) selected on herd size, breed composition and membership in the official milk-recording scheme. In the autumn, cows within each herd were blocked according to breed, parity and stage of lactation and allocated to two treatments: autumn trimming (AT) or no autumn trimming (NAT). Outcome variables were claw measurements and prevalence of hoof lesions and lameness (measured at spring trimming) and the need for hoof treatments between scheduled trimmings. At spring trimming, NAT cows had longer and shallower claws than AT cows. The average net growth of the toe wall was greater for AT than for NAT cattle, with a marked variation between housing systems. Most hoof lesions present at AT had disappeared at the subsequent spring trimming. Controlled for clustering by herd-within-year and for the effects of individual-and herd-level covariates, AT cattle at spring trimmings had significantly lower odds of lameness (OR=0.66) and of haemorrhages of the sole or white-line (OR=0.86), sole ulcer (OR=0.59) and white-line fissure or double sole (OR=0.71)-but not of moderate-to-severe heel-horn erosion or dermatitis (OR=0.96). Acute hoof treatments between claw trimmings were more common in the NAT group (OR=2.02).     

Evaluation of the efficacy of prophylactic hoof health examination and trimming during midlactation in reducing the incidence of lameness during late lactation in dairy cows

OBJECTIVE: To assess the efficacy of prophylactic hoof health examination and trimming during midlactation at reducing the incidence of lameness during late lactation in dairy cows. DESIGN: Randomized field trial. ANIMALS: 333 Holstein cows. PROCEDURES: Cows without apparent lameness were randomly allocated into 1 of 2 groups approximately 204 days after calving. Cows allocated to the treatment group (n = 161) were examined on a tilt table for diagnosis and underwent hoof-trimming procedures, if needed, for treatment of hoof disorders or lesions. Cows in the control group (n = 172) were not examined. Cows were assigned a locomotion score weekly for 28 weeks after allocation to a group. The number of cows classified as lame during late lactation (approx 205 to 400 days after calving) was compared between groups to assess the efficacy of prophylactic examination and trimming. RESULTS: Incidence of lameness during late lactation was 24% in cows in the control group and 18% in cows in the treatment group. CONCLUSIONS AND CLINICAL RELEVANCE: The 25% decrease in number of new cases of lameness in cows undergoing prophylactic hoof health examination and trimming during midlactation may be relevant for the well-being of dairy cows and should not represent a major economic burden to producers.     

Topical treatment of digital dermatitis associated with severe heel-horn erosion in a Swedish dairy herd

Two experiments were run in a commercial dairy herd to test the efficacy of topical treatments of digital dermatitis associated with severe heel-horn erosion. In Experiment I, topical treatments with solutions of either glutaraldehyde or oxytetracycline were compared with foot trimming and cleansing alone. After trimming of all feet, one front and one rear foot in each cow were treated with either glutaraldehyde or oxytetracycline (regardless of dermatitis status), while the other feet were used as controls and only trimmed. Two hundred foot records were obtained from 34 Swedish Red and White and 16 Swedish Holstein cows. The proportions (p) of feet cured from digital dermatitis were compared between each group of medically treated feet and the control feet, assuming the feet to be independent observations with respect to curing. Oxytetracycline was significantly more effective than hoof trimming alone (p=0.87 and 0.34, respectively; P<0.001) and than glutaraldehyde (p=0.41; P=0.004). Treatment with glutaraldehyde was no more effective than hoof trimming alone.In Experiment II, a specially designed footbath with two longitudinal compartments was used to study the effectiveness of a solution of acidic ionised copper in preventing or curing digital dermatitis. The footbath--using water in one compartment--was constructed to make within-cow comparisons of treatment efficacy possible. The hoof health of 44 dairy cows (also included in Experiment I) were studied when the animals first were turned out to pasture and at the end of the grazing season (approximately 6 months later). During the grazing season, the cows were walked through the footbath twice daily after milking for a total of 47 days, divided into five separate periods ranging in length from 3 to 16 days. As judged by a two-sample comparison of proportions, a higher proportion of the cows' hind feet that were affected by dermatitis were cured by the copper solution (20/24) than by water alone (12/23). The copper solution had no significant preventive effect on healthy feet.     

Influence of individual competition level on back kinematics of horses jumping a vertical fence

REASONS FOR PERFORMING STUDY: The costs and investments required for the purchase and training of showjumpers justify the need to find selection means for jumping horses. Use of objective kinematic criteria correlated to jumping ability could be helpful for this assessment. OBJECTIVES: To compare back kinematics between 2 groups of horses of different competition levels (Group 1, competing at high level; Group 2 competing at low level) while free jumping over a 1 m vertical fence. METHODS: Three-dimensional recordings were performed using 2 panning cameras. Kinematic parameters of the withers and tuber sacrale (vertical displacement, vertical and horizontal velocities), backline inclination and flexion-extension motion of the 3 main dorsal segments (thoracic, thoracolumbar and lumbosacral) were analysed. RESULTS: Group 2 horses had a lower displacement of their withers and tuber sacrale from the end of the last approach stride until the first departure stride (P<0.05). As a result, they increased the flexion of their thoracolumbar and lumbosacral junctions during the hindlimb swing phase before take-off (P<0.05). However, withers and tuber sacrale velocities were slightly modified. Group 1 horses pitched their backline less forward during the forelimb stance phase before take-off and straightened it more after landing (P<0.05), probably indicating a more efficient strutting action of their forelimbs. CONCLUSIONS AND POTENTIAL RELEVANCE: Because significant differences in back motion were found between good and poor jumpers when jumping a 1 m high fence, criteria based on certain back kinematics can be developed that may help in the selection of talented showjumpers.     

Effects of balancing and shoeing of the forelimb feet on kinematic gait analysis in five horses with navicular disease

The effects of balancing the foot and shoeing (B&S) on the kinematics of five Quarter Horses with navicular disease were evaluated using computerized gait analysis. Kinematic measurements of the right forelimb and head were made before and after palmar digital nerve block (PDNB) and before and after B&S of the forelimb feet. Carpal and fetlock joint angle, foot displacement, and temporal gait measurements were made for at least five strides in each horse trotting on a treadmill. Kinematic measurements were compared before and after PDNB and before and after B&S by analysis of variance with an α=0.05. The most significant kinematic changes seen after PDNB were in the vertical head movement parameters studied. Total vertical head excursion and measures of head height asymmetry between right and left forelimb stance phases decreased after PDNB. After B&S mean carpal flexion and maximum hoof height during the swing phase of the stride increased, but none of the head movement parameters significantly changed. Results of this study indicate that the ability of treadmill kinematic gait analysis to evaluate for improvement in lameness by monitoring vertical head movement parameters is not significantly affected in horses with navicular disease three weeks after balancing and shoeing the forelimb feet.     

The Forelimb and Hoof Conformation in a Population of Mongolian Horses

This article describes the lower limb and hoof conformation of a population of semi-feral Mongolian horses living on an open tundra/steppe environment. Data were collected from a convenience sample of 120 Mongolian horses used in the 2011 Mongolian Derby. Digital images of the hooves were obtained, and the lower limb conformation was assessed by four veterinarians involved in the screening of the horses offered for the derby. The horses were predominantly geldings (96%, 100/104), approximately 8.6 ± 2.5 years old, and 137 ± 8 cm at the withers. None of the horses were subjected to routine hoof trimming. Based on a 7-point linear score, lower limb conformation was normal, with a trend (>1 linear score deviation) slightly toward carpal valgus, mildly offset cannon (third metacarpal), and valgus at the matacarpophalangeal joint. Hoof measurements were within the norm for horses of this size. Fetlock valgus was associated with a smaller hoof width:length ratio (P = .016). None of the other hoof measurements were significantly associated with abnormal conformation scores. Overall, few conformation abnormalities were observed, and hoof shape and size was within the normal expected range for horses of this size. The hoof conformation in this population of Mongolian horses represented the natural interaction of the hoof with the environment.     

High speed field kinematics of foot contact in elite galloping horses in training

Reasons for performing study: Mechanical characterisation of the high speed gallop has significant importance for animal welfare and basic biology. Kinematic parameters such as the velocity of each foot at contact can inform theories of why animals gallop, and supplant epidemiological investigation into the mechanisms of musculoskeletal injury. Objective: To determine the velocity at which the fore and hind hooves of elite galloping horses impact the surface. Methods: High speed videography was used to measure the horizontal and vertical velocity of the hoof immediately prior to impact, and the subsequent sink (vertical) and slip (horizontal) distances travelled by the hoof into the surface. Horse speed ranged from 11–19 m/s. In total 170 forelimb and 168 hindlimb foot falls from 89 horses were analysed. Results: Horizontal and vertical hoof velocity increased with speed (P<0.001). Horizontal hoof velocity was significantly greater in the hindlimbs compared to the forelimbs (P<0.001) and was greater in the nonlead limbs compared to the lead limbs (P<0.001). Vertical hoof velocity was significantly greater in the lead limb than the nonlead limb (P<0.001). Overall, forelimbs contacted the ground with a more acute velocity vector angle than hindlimbs (P<0.001). Lead limbs contacted the ground at more acute angles than nonlead limbs (P<0.001). Vertical and horizontal velocities were highly correlated to sink and slip distance. Conclusion: Hindlimbs impact the surface at higher velocity than forelimbs, which is likely to result in higher peak impact forces in the hindlimbs. This runs counter to the finding of lower incidence of injury in hindlimbs. Potential relevance: Explanations consistent with these findings include the hindlimbs more effectively dampening peak impact forces, or that other injury mechanisms, such as limb vibration and limb load at mid stance, play an important role in injury.     

Effect of hoof trimming before the dry period on productive performance in perinatal dairy cows

To investigate the effect of hoof trimming before the dry period, the hooves of 10 cows (trimmed group) were trimmed at 79.6 +/- 8.6 days before parturition and the hooves of 52 cows were left untrimmed (control group). Blood biochemistry and hormone concentrations were investigated for 6 cows from each group. The daily milk yield after parturition in the trimmed group tended to be higher than that of the control group. Between 0 and 30 days after parturition, the levels of non-esterified fatty acids were significantly lower stet, and the plasma glucose and glucose disposal rates were significantly higher in the trimmed group. The plasma cortisol concentration was stable before and after parturition in the trimmed group. Hoof trimming before the dry period appears to reduce stress and maintain the nutritional conditions of perinatal dairy cows.     

Locomotion scores and lying behaviour are indicators of hoof lesions in dairy cows

Locomotion scoring, lying behaviour and lesion recording during hoof trimming are all ways of evaluating hoof health in dairy cows. The objective of this study was to evaluate the relationship between these measures in a random sample of 1340 cows from 42 Danish dairy herds. The hypothesis was that locomotion scoring and/or the monitoring of lying behaviour could be used as tools to identify cows with hoof lesions, either of the horn or of the skin. Cows were locomotion scored, lying behaviour recorded and data on hoof lesions seen during hoof trimming collected. The results were analysed using logistic regression with hoof lesion as the outcome and locomotion score (1-5), mean duration of lying bouts, parity and lactation stage as explanatory variables. This analysis was undertaken for all types of lesions, for hoof horn lesions only and for skin lesions only. Odds of all hoof lesions and of skin lesions increased with increasing locomotion score and increasing mean duration of lying bouts. Odds of horn lesions also increased with increasing locomotion score, but there was no significant association between horn lesions and the mean duration of lying bouts. It was concluded that locomotion scoring and duration of lying bouts may be used as tools in the management of hoof health in dairy herds.     

Clinical Outcome of 14 Obese,Laminitic Horses Managed with the Same Rehabilitation Protocol

A specific method of rehabilitation was used to manage obese horses with laminitis, and clinical outcome was evaluated after 5 to 20 months. Clinical data from 14 similar laminitis cases were statistically analyzed to evaluate response to rehabilitation. Data were analyzed using repeated measures or logistic regression methodologies. Each horse presented as obese and laminitic with no history of a systemic inflammatory disease. The rehabilitation method emphasized a mineral-balanced, low nonstructural carbohydrate diet; daily exercise; hoof trimming that minimized hoof wall loading; and sole protection in the form of rubber hoof boots and/or hoof casts. Distal phalanx alignment within the hoof capsule was significantly improved, and hoof wall thickness was significantly decreased (P < .0001) following treatment. Solar depth was significantly increased (P < .0015). Reduction of palmar angle measurements was detected in acutely and chronically affected horses. This treatment effect was statistically greater for horses with chronic laminitis than for horses with acute laminitis (P interaction < .0001). Horses were 5.5 times more likely to be sound post-treatment than before treatment. Daily exercise, dietary modification, and removal of ground reaction force from the hoof wall were foci of the rehabilitation program. Hoof care and husbandry as applied to these horses may be an effective method of rehabilitation of horses from obesity-associated laminitis.     

Influence of feeding regime on timing of parturition in beef cattle and the relationship of vaginal temperature to parturition

The timing of parturition was recorded for a total of 56 beef cattle (Japanese Black × Holstein Friesian) on different dietary treatments. The rate of calving during daylight hours in cows night‐fed (18.00 hours) with a roughage diet was significantly higher than that in cows night‐fed with a high concentrate diet (79.2% vs 38.5%, P < 0.05). Subsequently, the vaginal temperature (VT) of these cows was analyzed using a cosinor method. When the feeding schedule was changed from twice daily (08.30 and 15.30 hours) to night feeding, the periodicity, the acrophase and the bathyphase, which were the parameters of the cosine curve, were unstable from the first day of night feeding until after day 6 (P < 0.05). Prior to parturition, the midline‐estimating statistic of rhythm (MESOR) and the amplitude for the cows that were fed a high‐roughage diet at night and that calved at night‐time were lower and larger, respectively, than that for the other treatments (P < 0.01). Based on these results, the time of parturition in most of the beef cows was influenced by feeding time and diet composition. Those cows that calved at night‐time in spite of night feeding had lower vaginal temperatures.     

Temperament assessments of lactating cows in three contexts and their applicability as management traits

The applicability of three behavioral assessments of lactating cows as management traits was verified. Flight responses to an approaching human (flight starting and walking distances, and flight walking speed) at pasture, entrance order into the milking parlour and step‐kick behavior to cup attachment were observed for 713 subject cows in six Australasian dairy farms. On all farms, cows were kept at pasture without any barn housing. Flight responses were measured once, and other assessments were recorded repeatedly for each subject cow. A principal component analysis was performed to verify whether these assessments appear to measure the same trait. A two‐way anova and correlation analyses were then used to test whether obtained principal components were affected by farm, age and milking stage of cows. Australian and some Japanese herd management systems were compared for flight distance using a one‐way anova and a multiple comparison test. Three behavioral assessments clustered in different principal components, indicating that these assessments did not appear to measure the same trait. Factor scores of four principal components were affected by farm (all, P < 0.01), and the scores of principal component 1, interpreted as fear of humans (r = ?0.16, P < 0.01), and component 2, interpreted as aversion to cup attachment (r = ?0.28, P < 0.01), were moderately correlated with age. These results emphasize the necessity of data standardization to reduce the non‐genetic variation resulting from these two affectors. The flight distance at pasture of herds in Australia (6.06 ± 2.85 m) was significantly (P < 0.05) different from the flight distances measured in paddocks (1.50 ± 0.82 m) and free‐stall barns (1.22 ± 1.09 m) in Japan. However, mean distances were not different between the Australian herds at pasture and the Japanese herds at pasture in tie‐stall barns (3.96 ± 2.16 m) or in a free‐stall barn (4.03 ± 1.79 m). This difference could be a result of the fact that only a single measurement was made, so that repeated measurement might improve the usefulness of flight distance as a management trait. In conclusion, it was verified that step‐kick behavior to cup attachment and flight responses to human approach were, although they have some affectors, applicable as objective management traits in lactating cows.     

Hoof Size and Symmetry in Young Catalan Pyrenean Horses Reared Under Semi-Extensive Conditions

Hoof balance and conformation have been researched extensively in performance horses. The aim of this study was to describe the solar length, width, area, and symmetry of fore and hind hooves of young Catalan Pyrenean horses (Cavall Pirinenc Català) reared under semi-extensive conditions and lacking any hoof care, trimming, or shoeing. Measurements were performed on the isolated limbs. Solar length, width, and surface area of 128 distal limbs obtained from 32 yearlings demonstrated no significant differences between left and right forelimbs or hind limbs for any variable (P = .413, .975, and .486, respectively). There were no significant differences between fore and hind limbs for length (P = .831), whereas the forehoof width and area were significantly larger than those of the hind limb (P < .001). Interindividual variability was low for hoof width and length (coefficient of variation, <10%) and slightly larger for solar area (coefficient of variation, <15%). All variables had very high left-right symmetry (≥98%). No relevant laterality could be identified (directional asymmetry indices <2%). Notwithstanding the absence of regular hoof care, young Catalan Pyrenean horses reared under semi-extensive conditions present homogenous hoof sizes and a high level of symmetry for hoof length, width, and solar area.     

Estimation of genetic parameters of conformation traits in Iranian Thoroughbred horses

The aim of this study was to estimate the genetic parameters of conformation traits in Iranian Thoroughbred race horses. The data set included the conformation records of 607 Thoroughbred horses. In this study, 10 conformation traits were recorded. The effect of sex was significant for length of back line (P < 0.05), withers height (P < 0.05), circumference of front cannon (P < 0.001), and circumference of hind cannon (P < 0.001). The effect of age was significant for all traits (P < 0.01). The genetic parameters were estimated by the restricted maximum likelihood (REML) method using DFREML program. The heritability estimates were for head length 0.39, length of back line 0.41, length of shoulder 0.24, heart girth 0.49, chest width 0.22, withers height 0.38, front cannon height 0.27, circumference of front cannon 0.30, hind cannon height 0.29 and circumference of hind cannon 0.34. The estimates of genetic correlation ranged from 0.18 to 0.96 and those of phenotypic correlation varied from 0.16 to 0.83.     

Treadmill study of the range of back movement at the walk in horses without back pain.

OBJECTIVE: To evaluate back movement during walking in horses. ANIMALS: 22 adult horses with no history or signs of back pain. PROCEDURE: 3-dimensional movements of markers on the hooves, head, and back were measured with a motion analysis system while the horses were walking on a treadmill. The positions of markers on the hooves, head, and the skin above the spinous processes of T5, T10, T16, L3, and 2 sacral vertebrae were recorded. From a minimum of 6 walking motion cycles/horse, marker movement and the time of occurrence of minimum and maximum marker positions within the motion cycle were determined. Angles were calculated between the markers on the head, T16, and S4 or S5 and between the markers on T5, T16, and S4 or S5. RESULTS: Lateral back movement was maximal at L3, where it reached (mean +/- SD) 3.5 +/- 0.8% of the horses' height at the withers. Maximum dorsoventral back movement was found at the sacrum, where it reached 4.7 +/- 1.3% of the height at the withers. In the horizontal plane, the angle between T5, T16, and S4 or S5 was altered by 11 +/- 2.5 degrees during the motion cycle. In the sagittal plane, the angle between the head, T16, and S4 or S5 was altered by 7 +/- 3 degrees. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study may be used as basic kinematic reference data for evaluation of back movement in horses.