Ability Of Horses Research Articles

Diagnosis and management of thyroid disorders and thyroid hormone supplementation in adult horses and foals.

Equine thyroid disorders pose a diagnostic challenge in clinical practice because of the effects of nonthyroidal factors on the hypothalamic-pituitary-thyroid axis, and the horse's ability to tolerate wide fluctuations in thyroid hormone concentrations and survive without a thyroid gland. While benign thyroid tumours are common in older horses, other disorders like primary hypothyroidism or hyperthyroidism in adult horses and congenital hypothyroidism in foals are rare. There is a common misunderstanding regarding hypothyroidism in adult horses, especially when associated with the clinical profile of obesity, lethargy, and poor performance observed in dogs and humans. Low blood thyroid hormone concentrations are often detected in horses as a secondary response to metabolic and disease states, including with the nonthyroidal illness syndrome; however, it is important to note that low thyroid hormone concentrations in these cases do not necessarily indicate hypothyroidism. Assessing equine thyroid function involves measuring thyroid hormone concentrations, including total and free fractions of thyroxine (T4) and triiodothyronine (T3); however, interpreting these results can be challenging due to the pulsatile secretion of thyroid hormones and the many factors that can affect their concentrations. Dynamic testing, such as the thyrotropin-releasing hormone stimulation test, can help assess the thyroid gland response to stimulation. Although true hypothyroidism is extremely rare, thyroid hormone supplementation is commonly used in equine practice to help manage obesity and poor performance. This review focuses on thyroid gland pathophysiology in adult horses and foals, interpretation of blood thyroid hormone concentrations, and evaluation of horses with thyroid disorders. It also discusses the use of T4 supplementation in equine practice.

The impact on physical performance, pain and psychological wellbeing of chronic low back pain patients during 12-weeks of equine- facilitated therapy intervention.

Equine - Facilitated Therapy (EFT), an equine environment, and horses themselves can meet many physical and mental health needs beyond diagnostic categories. The horse's ability to produce a walk-like movement and the participant's ability to connect to non-judgemental living creatures, both of which can benefit participation and construct a positive self-image for chronic pain patients. The objective of this study is to evaluate the impact of EFT on perceived physical performance, level of pain, pain acceptance, depression and anxiety, and quality of life within a 12-week intervention for chronic low back pain (LBP) patients. Twenty-two LBP patients received EFT led by physical therapists as part of the public health services. A mixed method design combining quantitative and qualitative methods was employed to detect the outcome of the intervention. The data were collected via questionnaires, interviews, and patient data repositories. An interview was voluntary for participants and included questions of one's health, visits to the pain clinic during 6 months and an open-ended question about the intervention. The coding of the data was completed independently by two persons using thematizing. The welfare of the attending horses was taken into consideration in basic training and for the research setting. Statistical analysis and paired t-tests detected the changes during a 12-week intervention. The results suggest a significant increase in Canadian Occupational Performance Measure (COPM) levels of satisfaction with self-selected performances. The Raitasalo's version of Beck's Depression Inventory (RBDI) level of anxiety and Chronic Pain Acceptance Questionnaire (CPAQ) did not change, whereas a decline in the amount of perceived RBDI depression was found combined with increased levels of SF-36 Mental Change Scores and COPM satisfaction with performance. Only two of the 22 participants returned with reoccurring symptoms after 6 months to the pain clinic. The participant interviews revealed three important domains of experience during coding: physical-, psychological-, and social that link to the research question and suggest impact for the recovery from the human-animal interaction.

Computed tomographic guidance for internal fixation of type II distal phalangeal fractures in 51 horses.

Type II distal phalanx (P3) fractures are a well-described cause of lameness in horses. Reports on outcome following internal fixation of type II P3 fractures are lacking, and with little emphasis on complications. To describe a technique for internal fixation of type II P3 fractures, and evaluate whether specific variables influenced post-operative complications or a horse's ability to return to work. Retrospective case series. Medical records of 51 horses with CT-guided internal fixation of type II P3 fractures were reviewed. Outcome data were acquired from race records and telephone interviews. Associations between independent variables and outcome were analysed using multivariable logistic regression. Eighty-six per cent (95% CI 74%-94%; n=44) successfully returned to work. Implant infection (n=15) and distal interphalangeal joint osteoarthritis (n=9) were the most common complications, with the latter reducing the likelihood of success (OR=0.09, 95% CI 0.01-0.7, P=.02). Implant infection increased the time to return to work (HR=0.5, 95% CI 0.2-0.9, P=.03). The odds of delayed infection decreased by filling the hoof defect with acrylic hoof adhesive rather than poly(methyl methacrylate) and deeply countersinking the screw head (OR=0.08, 95% CI 0.02-0.38, P=.001); the individual effect of each treatment is unknown. Radiographic healing was not associated with likelihood of success. Study limitations included variation in follow-up methods, lack of control population for comparison and lack of randomisation of treatment protocols. Internal fixation of type II P3 fractures is an effective treatment that allows horses to return to athletic use, with similar improved success rates as those reported for conservative management. Infection rates were reduced by deeply countersinking the screw head and filling the hoof defect with an acrylic that mimics hoof wall flexibility and provides a secure seal. Recommencement of training should be based on clinical rather than strictly radiographic findings.

Effects of hair coat characteristics on radiant surface temperature in horses.

Horse owners may lack knowledge about natural thermoregulation mechanisms in horses. Horses are managed intensively; usually stabled at night and turned out during the day. Some are clipped and many wear a blanket, practices which reduce the horse's ability to regulate heat dissipation. The aim of this study was to investigate the relationship between hair coat characteristics, body condition and infrared surface temperatures from different body parts of horses. Under standard conditions, the body surface temperature of 21 adult horses were investigated using infrared thermography. From several readings on the same body part, a mean temperature was calculated for each body part per horse. Detailed information on horse breed, age, management and body condition was collected. Hair coat samples were also taken for analyses. A mixed statistical model was applied. Warmblood horse types (WB) had lower hair coat sample weights and shorter hair length than coldblood horse types (CB). The highest radiant surface temperatures were found at the chest 22.5±0.9°C and shoulders 20.4±1.1°C and WB horses had significantly higher surface temperatures than CB horses on the rump (P<0.05). Horses with a higher hair coat sample weight had a lower surface temperature (P<0.001) and hind hooves with iron shoes had a significant lower surface temperature than unshod hind hooves (P=0.03). In conclusion, individual assessment of radiant surface temperature using infrared thermography might be a promising tool to gather data on heat loss from the horses' body. Such data may be important for management advice, as the results showed individual differences in hair coat characteristics and body condition in horses of similar breeds.

Exploring the genetics of trotting racing ability in horses using a unique Nordic horse model

BackgroundHorses have been strongly selected for speed, strength, and endurance-exercise traits since the onset of domestication. As a result, highly specialized horse breeds have developed with many modern horse breeds often representing closed populations with high phenotypic and genetic uniformity. However, a great deal of variation still exists between breeds, making the horse particularly well suited for genetic studies of athleticism. To identify genomic regions associated with athleticism as it pertains to trotting racing ability in the horse, the current study applies a pooled sequence analysis approach using a unique Nordic horse model.ResultsPooled sequence data from three Nordic horse populations were used for FST analysis. After strict filtering, FST analysis yielded 580 differentiated regions for trotting racing ability. Candidate regions on equine chromosomes 7 and 11 contained the largest number of SNPs (n = 214 and 147, respectively). GO analyses identified multiple genes related to intelligence, energy metabolism, and skeletal development as potential candidate genes. However, only one candidate region for trotting racing ability overlapped a known racing ability QTL.ConclusionsNot unexpected for genomic investigations of complex traits, the current study identified hundreds of candidate regions contributing to trotting racing ability in the horse. Likely resulting from the cumulative effects of many variants across the genome, racing ability continues to demonstrate its polygenic nature with candidate regions implicating genes influencing both musculature and neurological development.

Zylkéne to load? The effects of alpha-casozepine on compliance and coping in horses during loading

Horses are routinely transported for access to safe off-road riding, veterinary care, breeding, sale, or moving to a new home environment. However, transport is a known stressor in horses. For this reason, problem behavior when loading is a commonly reported issue, which presents risks to handlers and horse welfare. Existing literature and manufacturers' recommendations suggests that alpha-casozepine may be effective in improving the behavior and welfare of horses during loading onto a vehicle for transport. The present article aims to assess the behavioral and physiological effects of a commercially available alpha-casozepine feed supplement (Zylkéne Equine) in horses during loading and confinement on a transport lorry. Subjects (n = 10) were loaded once with the supplement and once without, in a balanced random order with each subject acted as their own control. The handler was blind to treatment. Time to load onto the lorry, and movement of feet, licking and chewing, and vocalizing within the lorry were recorded as behavioral indicators of compliance and coping. Heart rate, heart rate variability, salivary cortisol, and infrared thermography of both core temperature and the discrepancy between eyes, were measured as indicators of arousal. There were no significant differences in physiology between treatment and control (P > 0.05). Treatment resulted in a significantly shorter loading time than control (P = 0.04); however, the actual difference in median time was only 0.45 seconds. No other behavioral indicator differed between treatment and control (P > 0.05). Power analysis revealed the sample was sufficient to detect a significant effect. Where modest effects were observed for a small number of variables, treatment effect contradicted predictions. Taken together, this indicates that alpha-casozepine does not affect a horse's ability to cope with loading and confinement in a horse lorry. Further work is required to ascertain whether the maximum dosage—twice that used here—might affect coping and behavior in horses.

Survey of human-horse relationships and veterinary care for geriatric horses.

OBJECTIVE To assess relationships between horse owners (or lessees) and geriatric or nongeriatric horses and to investigate factors influencing veterinary care decision-making. DESIGN Descriptive, cross-sectional, survey-based study. SAMPLE 2,879 people who owned or leased ≥ 1 horse. PROCEDURES Participants were recruited through social media and online horse forums to participate in an online survey about their horses, including measures of attachment, veterinary care decision-making, and experiences surrounding the death of a horse. Data were collected for primary horses (those respondents interacted with most) and secondary horses. Horses were further categorized as geriatric (≥ 20 years of age) and nongeriatric. RESULTS Geriatric primary horses were considered companion animals, retired, or used as part of a business significantly more frequently, and described as competition horses significantly less frequently, than nongeriatric horses. Geriatric horses were owned or leased significantly longer than nongeriatric horses, but the degree of respondents' attachment did not differ for geriatric versus nongeriatric horses. When respondents reported the death of a horse in the previous year, euthanasia was associated with higher levels of bereavement than death by other means. Death of geriatric horses most commonly followed a chronic illness and was associated with significantly higher levels of bereavement than death of nongeriatric horses. Among factors influencing decisions regarding expensive or long-term medical care, the horse's ability to lead a comfortable life was ranked highest. Respondents with geriatric horses made numerous accommodations for their care. CONCLUSIONS AND CLINICAL RELEVANCE Results provided important initial information about the relationships people have with geriatric horses. Understanding how individuals perceive their horses and how they make decisions regarding complex veterinary care is critical in informing effective client communication.

To pace or not to pace: a pilot study of four- and five-gaited Icelandic horses homozygous for the DMRT3 'Gait Keeper' mutation.

The Icelandic horse is a breed known mainly for its ability to perform the ambling four-beat gait 'tölt' and the lateral two-beat gait pace. The natural ability of the breed to perform these alternative gaits is highly desired by breeders. Therefore, the discovery that a nonsense mutation (C>A) in the DMRT3 gene was the main genetic factor for horses' ability to perform gaits in addition to walk, trot and canter was of great interest. Although several studies have demonstrated that homozygosity for the DMRT3 mutation is important for the ability to pace, only about 70% of the homozygous mutant (AA) Icelandic horses are reported to pace. The aim of the study was to genetically compare four- and five-gaited (i.e. horses with and without the ability to pace) AA Icelandic horses by performing a genome-wide association (GWA) analysis. All horses (n=55) were genotyped on the 670K Axiom Equine Genotyping Array, and a GWA analysis was performed using the genabel package in r. No SNP demonstrated genome-wide significance, implying that the ability to pace goes beyond the presence of a single gene variant. Despite its limitations, the current study provides additional information regarding the genetic complexity of pacing ability in horses. However, to fully understand the genetic differences between four- and five-gaited AA horses, additional studies with larger sample materials and consistent phenotyping are needed.

PERBANDINGAN NILAI BIOLOGIS PAKAN LOKAL DAN IMPOR PADA ANAK KUDA PACU INDONESIA

ABSTRACT COMPARISON OF BIOLOGICAL VALUE OF LOCAL AND IMPORT FEED IN INDONESIAN CHILD RACE HORSE. This research aims to determine the livestock child race horse's ability to digest feed, both local and imported feed. Digestibility of nutrients is a factor that determines the quality of feed ingredients or feed consumed by the livestock horses. This research used Statistics t-test method.Techniques of data retrieval are interviews and direct observations at sites of breeding racehorses. Data collected ie the type of local feed (corn, rice bran, fish meal, soybean, mung beans, coconut cake) and the types of imported feed (sustaina). The amount of feed (forage and concentrates) were given to livestock of child racehorse obtain the amount of feces (g / head / day) is then taken as many as 12 samples each of 8 racehorses using local feed and 4 racehorses use imported feed. The variables measured are digestibility of energy and protein digestibility. The results of the research are digestible energy (local feed ± 85.92 and imported feed ± 87.58) and protein digestibility (local feed ± 75.86 and imported feed 86.89 ±). T test, showed that the energy digestibility of feed imports give effect not significantly different (P&gt; 0.05) compared to local feed while the digestibility of protein feed imports significantly different (P &lt;0.01) in comparison with the local feed. Based on these results it can be concluded that the digestibility of protein for imported feed better than the local feed. Keywords: livestock horses, local feed, imported feed, digestibility

Development of a standard test to assess negative reinforcement learning in horses

Most horses are trained by negative reinforcement. Currently, however, no standardised test for evaluating horses’ negative reinforcement learning ability is available. The aim of this study was to develop an objective test to investigate negative reinforcement learning in horses. Twenty-four Icelandic horses (3 years old) were included in this study. The horses were tested in a pressure-release task on three separate days with 10, 7 and 5 trials on each side, respectively. Each trial consisted of pressure being applied on the hindquarter with an algometer. The force of the pressure was increased until the horse moved laterally away from the point of pressure. There was a significant decrease in required force over trials on the first test day (P<0.001), but not the second and third day. The intercepts on days 2 and 3 differed significantly from day 1 (P<0.001), but not each other. Significantly stronger force was required on the right side compared to the left (P<0.001), but there was no difference between first and second side tested (P=0.56). Individual performance was evaluated by median-force and the change in force over trials on the first test day. These two measures may explain different characteristics of negative reinforcement learning. In conclusion, this study presents a novel, standardised test for evaluating negative reinforcement learning ability in horses.

Retrospective study on the effect of wither fracture on racing performance in Thoroughbred racehorses in Hong Kong (2003 to 2013)

SummaryThe training programme for Thoroughbred flat racehorses is intense, with pressure to limit nontraining days. Fracture of the dorsal spinous processes is a traumatic event that affects a horse's ability to train and race, with little information available regarding short‐term treatment and long‐term outcomes for elite racing horses. Using a retrospective cohort study of the Hong Kong Jockey Club's veterinary clinical records, cases of wither fracture were identified radiographically, with clinical features, treatment and subsequent return to training and racing described. The prevalence of wither fracture was 0.152% and in 6 out of 8 cases, the fracture occurred following identified trauma. Clinical signs varied from mild swelling and pain of the affected region to acute, severe forelimb lameness with spinal deformation. Prognosis for recovery was excellent, with all horses returning to a level of racing performance equal to or better than before the injury. The time from injury to return to ridden work was &lt;2.5 months and return to racing was 9 months, with horses that returned to training sooner after injury having more favourable outcomes. The period of rest identified in this study was shorter than previously reported, with the median interval between injury and first gallop &lt;2.5 months and most horses back racing within 6 months.

Interspecific communication from people to horses (Equus ferus caballus) is influenced by different horsemanship training styles.

The ability of many domesticated animals to follow human pointing gestures to locate hidden food has led to scientific debate on the relative importance of domestication and individual experience on the origins and development of this capacity. To further explore this question, we examined the influence of different prior training histories/methods on the ability of horses (Equus ferus caballus) to follow a momentary distal point. Ten horses previously trained using one of two methods (Parelli™ natural horsemanship or traditional horse training) were tested using a standard object choice task. The results show that neither group of horses was initially able to follow the momentary distal point. However, after more experience with the point, horses previously trained using the Parelli natural horsemanship method learned to follow momentary distal points significantly faster than those previously trained with traditional methods. The poor initial performance of horses on distal pointing tasks, coupled with the finding that prior training history and experimental experience can lead to success on this task, fails to support the predictions of the domestication hypothesis and instead lends support to the two-stage hypothesis.

The effect of the 'Gait keeper' mutation in the DMRT3 gene on gaiting ability in Icelandic horses.

A nonsense mutation in DMRT3 ('Gait keeper' mutation) has a predominant effect on gaiting ability in horses, being permissive for the ability to perform lateral gaits and having a favourable effect on speed capacity in trot. The DMRT3 mutant allele (A) has been found in high frequency in gaited breeds and breeds bred for harness racing, while other horse breeds were homozygous for the wild-type allele (C). The aim of this study was to evaluate further the effect of the DMRT3 nonsense mutation on the gait quality and speed capacity in the multigaited Icelandic horse and demonstrate how the frequencies of the A- and C- alleles have changed in the Icelandic horse population in recent decades. It was confirmed that homozygosity for the DMRT3 nonsense mutation relates to the ability to pace. It further had a favourable effect on scores in breeding field tests for the lateral gait tölt, demonstrated by better beat quality, speed capacity and suppleness. Horses with the CA genotype had on the other hand significantly higher scores for walk, trot, canter and gallop, and they performed better beat and suspension in trot and gallop. These results indicate that the AA genotype reinforces the coordination of ipsilateral legs, with the subsequent negative effect on the synchronized movement of diagonal legs compared with the CA genotype. The frequency of the A-allele has increased in recent decades with a corresponding decrease in the frequency of the C-allele. The estimated frequency of the A-allele in the Icelandic horse population in 2012 was 0.94. Selective breeding for lateral gaits in the Icelandic horse population has apparently altered the frequency of DMRT3 genotypes with a predicted loss of the C-allele in relatively few years. The results have practical implications for breeding and training of Icelandic horses and other gaited horse breeds.

Dancing with Horses: Combining Dance/Movement Therapy and Equine Facilitated Psychotherapy

This qualitative research study explores the ways in which dance/movement therapy (DMT) and equine facilitated psychotherapy (EFP) can be combined to produce an integrated, creative, and effective psychotherapeutic approach. Interview methodology was used to collect qualitative data from current psychotherapeutic practitioners with experience in both disciplines. Interviews were transcribed, coded, and organized into 16 themes nested within 5 categories. The results showed a natural therapeutic fit between DMT and EFP, including the innate ability of horses to co-facilitate body-centered, movement-oriented, therapeutic processes. The results also suggested that combining DMT and EFP can increase therapeutic possibilities, including levels of client and therapist embodiment and creative expression, opportunities for contact and touch, and the depth and breadth of the therapeutic relationship. Finally, the results described some of the tools and techniques currently being used in DMT–EFP sessions and highlighted factors necessary to be successful in this endeavor. This study is intended to provide a foundation for further research and writing about combining DMT and EFP.

Electromyographic evaluation of approach stride, jump stride and intermediate stride in selected superficial muscles of the jumping horse: a preliminary study

The horse's ability to execute the diverse physical demands of jumping is greatly influenced by muscular adaptations to training. The aim of the study was to provide preliminary insight into potential differences in the functional activity of muscles recruited during phases of the equine jumping effort. An exploratory case study was conducted to investigate muscle activity and recruitment in one jumping horse, experienced in 1.40 m competition. Wireless sEMG electrodes were utilised to quantitatively investigate the degree of muscle activation by recording potentials from the Superficial gluteal (SG), Triceps brachii (TB) and Longissimus dorsi muscles. Data were collected as the horse executed a related combination of fences with a maximum height of 1.25 m. Mean motor unit action potential (mMUAP) and mean peak amplitude frequency (PAF) were determined for each muscle during approach, jump and intermediate strides, and were analysed using Friedman and Wilcoxon Signed Rank tests to establish whether significant differences occurred between strides. Statistical analyses did not reveal significant differences between mMUAP values for muscles investigated across strides (P≯0.05). However, significant differences were found for mean PAF values in the left SG between approach and jump strides (P&lt;0.025), and between jump and intermediate strides (P&lt;0.025) in the left TB. The lack of significant differences between strides may reflect the theory that the jump stride is a form of extended suspension incorporated into the canter stride and may support current anecdotal training methods of the jumping horse, which place emphasis on developing a regular and collected canter. However, results from this study were based on one horse and therefore application to the wider population of jumping horses should be undertaken with caution until further research in more subjects is conducted to support the results from this preliminary study.

Reduction of the olfactory cognitive ability in horses during preslaughter: Stress-related hormones evaluation

As horses may perceive several odour signals of danger at slaughter, application of mentholated ointment to their nostrils may limit their perception of danger. To assess the effect of the application of a mentholated ointment to horse nostrils on the stress response during pre-slaughter handling, plasma levels were evaluated for cortisol, beta-endorphin, epinephrine and norepinephrine prior to and after stunning. Twenty draught-type horses were divided into control (n=10) and treated (n=10) groups and a mentholated ointment applied to the nostrils of the treated horses following blood sampling in lairage 45min prior to slaughter. Treatment did not affect plasma concentrations of beta-endorphin or cortisol but significantly reduced the concentrations of epinephrine and norepinephrine observed in post-stun plasma. These results indicated that mentholated ointment applied to the nostrils of horses pre-slaughter reduced their adrenergic response to the slaughter environment, implying that the stress response may be reduced with this technology.

Presales radiographic surveys in yearlings 1. Image interpretation and significance of lesions in the fetlock

The sale of thoroughbreds, whether via public auction or privately, frequently demands the use of prepurchase radiography. This is may be carried out by the vendor in advance of a...

Laboratory findings in respiratory fluids of the poorly-performing horse

Any disorder impairing a performance horse's ability to ventilate its lungs and exchange oxygen compromises exercise performance in any discipline. Since bronchoalveolar lavage was described in horses in the early 1980s, laboratory evaluation of respiratory fluids, along with clinical and functional assessment of the respiratory system, has become a relevant step in the diagnosis of respiratory disease affecting performance. The aim of this review is to provide objective information to assist clinicians in interpreting laboratory findings by (1) summarising published cytological references values in both clinically healthy horses and those with various airway diseases, (2) assessing the influence of physiological circumstances, such as exercise, on the cytological evaluation, (3) discussing the relationship between cytological and microbiological analyses, clinical signs and respiratory function, and (4) suggesting how this latter relationship may affect performance.

Effects of different bits and bridles on frequency of induced swallowing in cantering horses

AbstractIt has been suggested that the presence of a bit reflexly increases salivation but, at the same time, interferes with the horse's ability to swallow. The objective of this study was to compare swallowing frequency in 12 horses exercising at canter while wearing a head collar, a bitless bridle, a jointed snaffle bit and a Myler correctional-ported barrel bit. Laryngeal movements were recorded videoendoscopically as the horses cantered (8 m s−1) on a high speed treadmill, with the use of side reins to flex the poll. Swallowing was stimulated artificially by infusion of sterile water at a constant rate of 5 ml min−1through a cannula in the endoscope's biopsy port. The results showed large differences in swallowing frequency between horses. Swallowing frequency was lower for the Myler snaffle than for the other conditions (P&lt;0.05). It is concluded that the presence of a bit does not preclude swallowing during exercise at canter with the poll in a flexed position, but certain types of bits may be associated with a reduction in swallowing frequency.

Musculoskeletal responses of 2-year-old Thoroughbred horses to early training. 5. Kinematic effects

AIM: To examine the effect of race training on kinematic parameters of the trot in a sample of 2-year-old Thoroughbred fillies. METHODS: Two-year-old Thoroughbred fillies that had been either trained for racing (n=7) or left untrained in small paddocks (n=7) were examined for lameness, and linear and temporal kinematic data were collected from video recordings of each horse trotted in-hand, 5, 9 and 13 weeks after the beginning of training. Horses were graded as: sound (Grade 0), suspected but not obviously lame (Grade 1), or definitely lame at the trot (Grade 2). RESULTS: Mean velocity at the trot did not vary with lameness grade. Compared with horses classified as sound (Grade 0), horses classified as suspected or definitely lame (Grades 1 and 2) had shorter (2.55 (SE 0.02) vs 2.41 (SE 0.02) and 2.44 (SE 0.03) m; p<0.001) and faster (671 (SE 3) vs 645 (SE 1) and 647 (SE 4) msec; p<0.001) strides. None of the linear or temporal parameters measured varied significantly between the successive observation periods. When data from sound horses were pooled, the training group trotted at a higher mean velocity (4.22 (SE 0.08) vs 3.22 (SE 0.06) m/sec; p<0.001) and with a longer stride length (2.79 (SE 0.05) vs 2.18 (SE 0.06) m; p<0.001) than the untrained group. The stride duration was longer (669 (SE 7) vs 662 (SE 9) msec; p=0.01), stance period was shorter (34.1 (SE 0.6) vs 39.3 (SE 0.7) %; p<0.001) and mid-stance was achieved earlier in the stride (12.1 (SE 0.6) vs 13.1 (SE 0.2) %; p=0.001) in the trained than the untrained group. A longer swing phase in the trained group was associated with an increase in retraction time (9.2 (SE 0.2) vs 7.6 (SE 0.3) %; p=0.001). CONCLUSIONS: These data indicate that early race training in young Thoroughbreds was associated with quantifiable changes in linear and temporal kinematic parameters of the trot, which were related to the race-training objective of improving the horse's ability to work at higher velocities. CLINICAL RELEVANCE: Race training resulted in changes in the gait of non-lame horses at the trot, which should be considered during veterinary lameness examinations.