Topic:Clinical Study
Clinical studies in equine research involve the systematic investigation of health and disease in horses through structured scientific methods. These studies aim to evaluate the safety and efficacy of treatments, understand disease mechanisms, and improve veterinary care practices. Clinical studies can include randomized controlled trials, observational studies, and case-control studies. They may focus on various aspects such as pharmacokinetics, therapeutic interventions, and diagnostic techniques. This page compiles peer-reviewed research studies and scholarly articles that explore the design, implementation, and findings of clinical studies in equine medicine, providing insights into their impact on horse health and veterinary practices.
Leucine, pyridoxine and resveratrol supplementation alter metabolic parameters in ponies with equine metabolic syndrome. Supplements claiming to improve metabolic profiles in equine metabolic syndrome (EMS) often lack scientific validation. Objective: To evaluate the effect of a supplement containing leucine, resveratrol and pyridoxine on the metabolic profile in ponies with EMS. Methods: Unmasked randomised, placebo-controlled field trial. Methods: Thirty-eight ponies completed the trial across five farms. Ponies were age and sex matched per farm and randomly assigned to the supplement (n = 20) or placebo group (n = 18) with owners masked to group assignments. Ponies were sampled at days -1/0 (T1), 7/8 ...
Time Attenuation Curves for Equine Intravenous Contrast Enhanced Skull CT Using the Medial Saphenous and Cephalic Veins. Intravenous (IV) contrast administration during computed tomography (CT) of the equine head is routinely performed to delineate the extent of disease and differentiate between vascular and nonvascular tissue. Current equine scan protocols are extrapolated from human and canine studies. There have been no prospective equine studies describing the optimal time to image the patient after administration of contrast or the optimal site of contrast administration. Therefore, the current postcontrast times to scan and sites of contrast administration may not be appropriate for use in horses. The obje...
Pharmacokinetics of a fipronil pour-on formulation and its efficacy against Dermacentor nitens (Acari: Ixodidae) in horses. The objective of this study was to standardize a stall-trial methodology for horses in order to evaluate the pharmacokinetics and efficacy of a 1 % fipronil pour-on formulation against Dermacentor nitens. Brazilian pony breed horses were housed in individual stalls within a covered barn and artificially infested with D. nitens larvae on alternate days from day -31 to -1 before treatment. The animals were treated on day 0 with a fipronil 1 % pour-on at a dose of 1 mg/Kg body weight. To determine the therapeutic efficacy, the number of engorged females naturally detached from control and t...
Preliminary assessment of the leukocyte coping capacity as a point of care marker in horses with stress associated diseases. Stress represents a serious health and welfare concern; however, its objective assessment remains difficult. The equine gastric ulcer syndrome (EGUS) and orthopedic diseases that cause pain are among stress associated diseases in equine medicine. The leukocyte coping capacity (LCC) quantifies oxygen radical generation of neutrophil granulocytes which is altered under stress. Therefore, LCC could be a novel biomarker for stress in horses and we hypothesized that horses with stress associated diseases would have lower LCC values in comparison to horses without these diseases. Methods: In this ob...
Evaluation of the impact of acepromazine on tissue oxygenation in horses sedated with detomidine. Sedation with α₂-agonists can impair microcirculation and oxygen delivery. This prospective randomized crossover study investigated whether administering acepromazine maleate before detomidine hydrochloride maintains higher peripheral tissue oxygen saturation (StO₂) in sedated horses. Eight healthy adult horses randomly received intravenous detomidine (10 μg/kg) either alone (D) or in combination with acepromazine (20 μg/kg; DA), with a one-week washout. Hemoglobin concentration and central venous oxygen saturation (ScvO₂) were measured at baseline. Tissue oxygen saturation, tissue ...
Impact of exercise frequency, race distance, age, and pregnancy stage on oxidative stress and lipid metabolism in purebred Arabian mares. Pregnancy causes increased oxidative stress in mares, possibly harming both the mare and the foal, whereas the effects of different exercise levels on oxidative stress and lipid metabolism during pregnancy remain unclear. Objective: For this reason, the aim of this research was to explore the impacts of different training intensities on oxidative stress and lipid metabolism during pregnancy. Methods: The study comprised 22 clinically normal Purebred Arabian mares from Algeria, which were divided into three groups according to age and exercise frequency. Blood samples were collected during both...
Preliminary investigation of equine veterinary hospital staff attitudes towards pain assessment in a single centre. Despite the availability of several equine pain assessment tools, their use in equine veterinary practice appears limited compared to small animal practice. This study explores potential barriers to equine pain assessment, as reported by staff at a single UK equine teaching hospital. Methods: Nine hospital staff members were interviewed using semi-structured interviews. Key themes were identified through reflexive thematic analysis. Results: Participants acknowledged the importance of pain assessment, yet highlighted limitations in current methods and their inconsistent use. Key challenges inc...
A modern AI framework integrating deep imputation, synthetic data balancing, and explainable modeling for survival prediction in horse colic. Artificial intelligence (AI) has emerged as one of the most transformative tools for developing clinical decision-support systems in veterinary medicine. Despite its growing use, its full potential remains underutilized in equine medicine, an area of both high economic and clinical importance. Accurate survival prediction in horses with colic is crucial for timely intervention and improved clinical outcomes. Methods: This study aimed to predict survival outcomes in horse colic cases by developing models that combine traditional machine-learning algorithms (XGBoost, Light Gradient Boosting Mach...
A novel dataset of 2,362 equine fecal microbiomes from veterinary teaching hospitals across three countries reveals effects of geography and disease. Horses and other equids are reliant on the gut microbiome for health, and studies have reported associations between certain clinical conditions and features of the fecal microbiome. However, research to date on the equine fecal microbiome has often relied on small sample sizes collected from single and relatively localized geographic regions. Previous work also largely employs single timepoint analyses, or horses selected based on limited health criteria. Results: To address these limitations and expand our understanding of the core microbiome in health, and the changes associated with advers...
Pharmacokinetics and Safety of a Single Subcutaneous or Intramuscular Dose of Ketamine in Healthy Horses. Pharmacokinetics (PK) of intramuscular (IM) and subcutaneous (SC) ketamine in horses has not been described. This study aimed to evaluate the PK and safety of ketamine and its metabolites after a single SC or IM administration. In Phase 1, two horses received 0.5 or 1 mg/kg of ketamine via SC and IM routes. In Phase 2, eight horses received 0.5 mg/kg IM. Plasma or serum concentrations of ketamine and major metabolites were determined by a validated liquid chromatography-mass spectrometry method at baseline and selected intervals post-administration. Subcutaneous administration resulted in ...
A Portable Fluorometer Detects Significantly Elevated Cell-Free DNA in Tracheal Wash and Bronchoalveolar Lavage Fluid in Horses with Severe Asthma. Severe equine asthma (sEA) is characterized by increased lower airway neutrophils that contribute to dysregulated inflammation through the release of cytokines, reactive oxygen species and neutrophil extracellular traps (NETs). NETs are composed of cell-free DNA (cfDNA) intercalated with enzymatic proteins and are known to be increased in the lower airway of asthmatic horses. The objectives of this study were two-fold: 1. Determine if cfDNA can be accurately measured in equine bronchoalveolar lavage fluid (BALF) and tracheal wash (TW) with a Qubit 4 fluorometer. 2. Determine whether Qubit-meas...
Long-Term Prognosis of Complete Rupture of the Superficial Digital Flexor Tendon in 25 Horses – A Retrospective Study. A total of 48 horses with unilateral (n = 44) or bilateral (n = 4) overstrain-induced complete rupture of the superficial digital flexor tendon (SDFT) in the forelimbs were retrospectively analysed. A telephone questionnaire, carried out an average of 5,9 years post-injury, served as a long-term follow-up in 25 horses. The mortality rate associated with SDF tendonitis was 12,0 % (3/25). Superficial digital flexor tendonitis did not recur in 76,0 % (19/25) of the horses, but at least one subsequent episode occurred in 24,0 % (6/25). The results of this study indicate that it is reasonable...
Metformin Protects Against Persistent Atrial Fibrillation in an Equine Model. Horses are one of the few animals that spontaneously develop atrial fibrillation (AF), making them a powerful model for studying AF mechanisms and treatment effects. Despite the initial effectiveness of treatment in horses and humans, AF-induced atrial remodeling compromises its long-term success. Observational studies have suggested that metformin may reduce the risk of AF, but its effects on progressive AF-induced atrial remodeling have yet to be evaluated in a high-fidelity large animal model. Unassigned: Here, we used a longitudinal horse model of tachypacing-induced self-sustained AF to c...
Subchondral and Osteochondral Unit Bone Damage in the Fetlock Region of Sport Horses Using Low-Field MRI: Case Series. Damage to the osteochondral unit is a common cause of lameness in horses. Published descriptions of MRI findings of osteochondral unit and subchondral damage are currently lacking, and only a few reports describe outcomes in sport horses. The aims of this case series retrospective study were to describe different MRI patterns of osteochondral/subchondral pathology in the fetlock joint using low-field MRI and to provide outcome information. A total of 35 sport horses were included. Data regarding detailed clinical history, treatment and outcome were evaluated. MRI identified a total of 39 bone ...
Equine coronary sinus and great cardiac vein anatomy relevant to cardiac electrophysiology. The coronary sinus (CS) and great cardiac vein (GCV) are crucial in cardiac electrophysiology and can be arrhythmogenic in humans. In horses, CS/GCV catheterisation is increasingly performed for arrhythmia diagnosis and treatment. Improved anatomical understanding of these structures is needed to clarify relationships to surrounding structures. Methods: Postmortem examinations of 64 adult warmblood equine hearts were carried out. Middle cardiac vein and vein of Marshall ostia locations were described. Right atrial myocardial sleeve (MS) length was measured from the CS ostium. In 23 horses, CS/...
Dexmedetomidine Prolongs the Duration of Ropivacaine Corneal Anesthesia After Subconjunctival Injection in Healthy Horses. To determine whether dexmedetomidine prolongs corneal anesthesia following subconjunctival ropivacaine injection in healthy equine eyes. Methods: Ten horses with normal ophthalmic exams were enrolled in a randomized, blinded, crossover experiment with a minimum 4-week washout between treatments. Baseline corneal touch thresholds (CTT, cm) were measured via esthesiometry and a subconjunctival injection was performed in the treatment eye with ropivacaine (R, 0.3 mL 0.5%) or dexmedetomidine-ropivacaine (DR, 0.1 mL 0.5 mg/mL + 0.2 mL 0.5%) and saline (control, 0.3 mL) in the contrala...
Metabolic Profiles of Finishing and Nonfinishing Horses in Uruguayan Raid Competitions. The Raid Hípico Uruguayo (RHU) is the oldest equestrian endurance sport in Uruguay. A high percentage of horses fail to complete RHU rides. Therefore, the aim of this study was to investigate whether weather conditions (comfort index [CI]), horse experience, and ride distance affect horse performance (finishing ride [FR] or nonfinishing ride [NFR]) in the RHU. An additional objective was to determine whether finishing the ride affects the hematological and biochemical parameters of the horses. This study involved 17 RHU rides over distances of 60-90 km and 284 horses. Blood samples were tak...
A Pilot Observational Study in Ohio, USA of the Healing of Our Veterans Equine Services Intensive Intervention for Veterans with Trauma Histories. : Equine-assisted services are being increasingly utilized as complementary interventions for military veterans who have experienced trauma. However, rigorous research is lacking, and randomized controlled trials are needed. The H.O.O.V.E.S. Intensive intervention was developed for this population. This intensive program is an equine-assisted learning approach developed for veteran and active-duty military trauma survivors. The program integrates equine-assisted learning, peer mentorship and experiential learning in a residential retreat format. The primary aim of this pilot study was to deter...
Progestagens Monitoring in 147 Mares in Order to Induce Foaling With Oxytocin. A total of 147 mares of different breeds (110 were sport or race horses, often very valuable) have been monitored over 5 years from 2012 to 2016. When at or near term, the mares were monitored in order to induce foaling, by checking the mammary development by palpation, analysing the colour and consistency of the precolostrum, estimating the calcium and antibodies concentrations in the precolostrum and by measuring the plasmatic progestagens concentration every day at 6 p.m. At the end of gestation, it has been observed that the progestagens rate levelled off (the top concentration varies from...
Bile acids segregate metabolic syndrome in a cohort of 100 deeply phenotyped horses. Metabolic syndrome (MetS)-encompassing obesity, insulin resistance, dyslipidemia, and hypertension-is prevalent in both humans and horses, offering a unique opportunity to explore shared pathophysiological mechanisms across species in a controlled model organism. In this first report from the Pioneer 100 Horse Health Project (P100HHP), we conducted a longitudinal, multi-omic analysis of 108 deeply phenotyped horses to interrogate individual health trajectories for precision insights into MetS. We identified two primary metabotypes: one characterized by elevated unsaturated triglycerides (TGs) ...
Physiological and behavioural effects of continuous remifentanil-xylazine administration in donkeys. Remifentanil and xylazine are used as continuous infusions to facilitate standing surgery in horses. Their use for this purpose has not been reported in donkeys. Objective: To evaluate the behavioural, sedative, and cardiorespiratory effects of continuous intravenous infusion of remifentanil and xylazine in donkeys. Methods: Non-blinded in vivo experiments. Methods: Ten donkeys were sedated with an intravenous bolus of xylazine (0.8 mg/kg). After 3 min, continuous infusions of xylazine (0.65 mg/kg/h) and remifentanil (6 μg/kg/h) were administered for 60 min. Cardiorespiratory physio...
Synovial chemokine and cytokine profiles in horses with and without systemic Borrelia burgdorferi infection. Lyme arthritis, a well-documented subtype of arthritis in humans and dogs, is caused by Borrelia burgdorferi and spread primarily through ticks (Ixodes spp.). While Lyme disease in horses is known to cause a variety of clinical signs, its involvement in the development of equine arthritis is controversial. As climate change enables tick populations to expand, more horses could be exposed to B. burgdorferi; therefore, a greater understanding of how Lyme disease affects joints is critical to preserving soundness. Objective: To determine if systemic, naturally occurring Lyme disease had a discern...
Intraligamentary anaesthesia: a local anaesthesia technique in equine dentistry. The injection of a local anaesthetic into the periodontal ligament (PDL) to achieve desensitisation of the pulp, periodontium, and adjacent tissues is a well-established technique in human dentistry, particularly in paediatric patients. This approach, commonly referred to as intraligamental or intraligamentary anaesthesia (ILA), has been widely adopted due to its effectiveness and relative simplicity. The aims of the present publication were: (1) to provide a review of the literature, (2) to describe an ILA technique adapted by the authors for use in equine dentistry, and (3) to evaluate this ...
Child horse harmony in motion: a preliminary study to explore heart rate synchronization in equine assisted therapy for neurotypical and ADHD children. Equine-Assisted Services (EAS) encompass a range of therapeutic interventions utilizing equine interactions to achieve therapeutic goals. This study explores heart rate synchronization between horses and riders during mounted and unmounted interactions, focusing on its potential implications for emotional regulation. A total of 25 participants aged 6-12 took part in the study, which included two groups: novice riders diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) (n = 15) and experienced neurotypical riders (n = 10). Heart rate measurements were obtained using Polar Equ...
Descriptive epidemiology of long-term injuries in jump racing Thoroughbreds in Great Britain. Race-related injuries in horse racing, especially those requiring extended recovery, are a welfare concern and threaten the sport's social licence. Previous studies predominantly report on fatalities; however, serious non-fatal musculoskeletal injuries often end horses' racing careers or have a high recurrence risk. No recent studies have described or quantified long-term injuries (LTIs) in racing Thoroughbreds, which is essential to inform targeted risk prevention strategies. Objective: To describe the types, frequencies and incidences of LTIs in British jump racing. Methods: Retrospective co...
Degenerative Changes in MCP/MTP Joints of Working Horses Without Lameness: Integrating CT-Based Assessment and Synovial Fluid Biomarkers. Working horses often develop distinct patterns of joint degeneration, yet research in this population remains limited. This study aimed to characterize degenerative changes in the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints of Serbian Mountain Horses using computed tomography (CT) and to explore their associations with synovial fluid (SF) biomarkers. A cross-sectional analysis was conducted on 32 MCP/MTP joints from eight clinically sound horses. Postmortem, joints underwent CT imaging, and SF samples were analyzed for viscosity, protein content, total nucleated cell count (...
Oral administration of pimobendan in healthy horses results in low plasma concentrations. To describe the pharmacokinetics of a single dose of pimobendan (Vetmedin) in healthy adult horses and provide preliminary evidence of the absorption of 2 compounded pimobendan formulations. Unassigned: From August 2022 through November 2022, 6 healthy adult horses were administered a single dose of 0.5 mg/kg pimobendan orally. A subset of 2 horses was also administered pimobendan, compounded as an oil-based suspension and a capsule formulation. Plasma was collected at times 0, 15, 30, and 45 minutes and 1, 2, 4, 8, 12, and 24 hours after administration. The plasma concentrations of pimobendan...
Reining in strangles: Absence of disease in horses vaccinated with a DIVA-compatible recombinant fusion protein vaccine, Strangvac, following natural exposure to Streptococcus equi subspecies equi. Strangles, caused by Streptococcus equi subspecies equi (S. equi), is a prevalent infectious disease of horses. This is the first report on the use of a new vaccine, Strangvac, in a natural outbreak of strangles. Objective: To measure the effects of Strangvac vaccination during an outbreak of strangles at a Swedish farm. Methods: Longitudinal cohort study. Methods: Healthy horses (n = 17) were vaccinated on day 0, which occurred 23 days after strangles was first confirmed in three unvaccinated horses on the same farm. Blood serum samples were collected on day 0, day 28 and day 489. A com...
Outcome of Standardbred racehorses following femoropatellar arthroscopy for osteochondrosis dissecans. To evaluate postoperative racing performance of a population of Standardbred racehorses following arthroscopic removal of an osteochondrosis dissecans (OCD) lesion of the femoropatellar joint. Methods: Retrospective study. Methods: A total of 45 client-owned Standardbred racehorses. Methods: OCD lesions were measured and graded using the length of the subchondral bone defect from preoperative radiographs. Postoperative racing results were obtained from the United States Trotting Association, and follow-up owner surveys were conducted. A control group of contemporaneous paternal siblings free o...
Preliminary Biometric Study on Symmetry of Hoof Solear Aspect in Forelimbs in Four Horse Breeds. Correct conformation and symmetry of bilateral hooves are associated with a properly balanced hoof, which has a significant impact on the biomechanics of movement and reduces the risk of injury. The aim of the study was to compare solear aspect dimensions of bilateral hooves in forelimbs (hoof width, length, frog width, length, medial and lateral diagonals) with regard to sex, breed and age of horses. The dimensions were measured with a calliper in 100 horses of four breeds. The results showed that the breed factor significantly affected all dimensions. Age was significant for some variables, ...