Topic:Equine Medicine
Equine Medicine encompasses the study and application of medical practices specifically related to the health and well-being of horses. This field involves the diagnosis, treatment, and prevention of diseases and disorders affecting equine species. It covers a wide range of topics, including internal medicine, surgery, reproduction, and pharmacology. Research in equine medicine often focuses on understanding the physiological and pathological processes unique to horses, as well as developing effective therapeutic interventions. This page aggregates peer-reviewed research studies and scholarly articles that explore various aspects of equine medicine, providing insights into the latest advancements and methodologies in the care and management of horse health.
Association of Equine Squamous and Glandular Gastric Disease with Dental Status in 54 Horses. Gastric pH is a key factor in the development of equine squamous gastric disease (ESGD). Although acid injury is unlikely the primary cause of equine glandular gastric disease (EGGD), low pH may promote mucosal damage. Gastric pH is influenced by roughage uptake, as chewing increases the alkaline saliva production. The proton pump inhibitor omeprazole is currently recommended by the American/European College of Veterinary/Equine Internal Medicine (ACVIM/ECEIM) for ESGD and EGGD. We hypothesized that dental disorders decrease saliva production and gastric pH, predisposing horses to EGUS. Gastro...
Detection of equine parvovirus-hepatitis and efficacy of governmental regulation for equine biologics purity. In 2018, a new virus, named equine parvovirus-hepatitis (EqPV-H), was discovered in a biologic product that had been administered to horses that subsequently developed clinical signs of equine serum hepatitis (Theiler disease). Further correlation of the virus with the disease sparked federal requirements that all equine biologics be free of EqPV-H. The initial quantitative real-time PCR (qPCR) test for EqPV-H has proved to be sensitive to co-extracted PCR inhibitors in template nucleic acids, causing false-negative results. We investigated the use of digital PCR (dPCR) as a more robust test. ...
A broad-spectrum peptide screening method using an optimized solid-phase extraction and liquid chromatography-high-field asymmetric ion mobility spectrometry-mass spectrometry for doping control in equine urine. The abuse of prohibited peptide-based drugs with a broad spectrum of chemical characteristics poses a significant concern for the horseracing industry. Recently, there has been a notable increase in positive cases of small-peptide drugs reported in equine and canine sports. In addition to small peptides, large peptides (over 2 kDa) with structural diversity have also entered the market in increasing numbers as drugs for humans and livestock. However, the simultaneous analysis of both small- and large-peptide-based drugs is still challenging. In this study, a screening method was developed to c...
Environmental impacts and daily voluntary movement of horses housed in pasture tracks as compared to conventional pasture housing. Pasture tracks are a modern equine housing trend often implemented as a weight control strategy due to the belief that they promote movement, though this is not proven experimentally. To test movement of horses housed in pasture tracks as compared to conventional pasture housing, two experiments were performed using a track (0.2ha, 3.5m in width, 561 m total distance) created around the perimeter of a 2.0 ha pasture. In experiment 1, eight horses were paired and rotated between three treatment locations: track (T), small 2 ha pasture housed within the track (SP), and a larger 20 ha pasture on ...
Intrathecal enalapril reduces adhesion formation in experimentally induced digital flexor tendon sheath injuries in horses. The objectives of the study were to describe a standing percutaneous adhesion induction model in the digital flexor tendon sheath (DFTS) of horses and to evaluate the effect of intrathecal administration of the angiotensin-converting enzyme (ACE) inhibitor enalapril on tendon healing and adhesion formation. Methods: Randomized, blinded, controlled experimental study. Methods: Eight healthy horses. Methods: A collagenase-induced adhesion model was implemented in the deep digital flexor tendon (DDFT) of both forelimbs under standing ultrasonographic guidance. Daily intrathecal injections of 5 ...
Prevalence of gastrointestinal and blood parasites in horses of Nakhon Si Thammarat province, Thailand. The global prevalence of gastrointestinal (GI) and blood parasite infections in horses is a significant concern due to their substantial impact on morbidity, mortality, and economic losses in the horse industry. In Thailand, limited research has been conducted on these parasites in horse populations, and data from southern Thailand are lacking. Consequently, this study aimed to estimate the prevalence of GI and blood parasites in horses in Nakhon Si Thammarat province, Thailand. Unassigned: In total, 79 fecal and blood samples were collected from horses across 11 farms in Nakhon Si Thammarat p...
Congenital urachal and urinary bladder defects leading to uroperitoneum in a neonatal quarter horse colt. A newborn (5 h old) quarter horse colt was presented because of lethargy and severe abdominal distention. Uroperitoneum was suspected during initial workup, based on sonographic imaging and peritoneal fluid analysis. Definitive diagnosis was confirmed during exploratory celiotomy. Surgery revealed a congenitally abnormal allantoic stalk/urachal remnant and a failure of embryological fusion of the dorsal bladder wall. Recovery was successful and the animal is now a healthy, 4-year-old western performance gelding. These specific congenital abnormalities have not been previously documented in the...
Evaluation of the Rostral Inferior Alveolar Nerve Block via the Mental Foramen in Equids: In Vivo Efficacy Testing. The use of proper sedative and regional anesthetic protocols is essential when performing equine dental surgical procedures under standing sedation. The efficacy of the rostral inferior alveolar nerve block via the mental foramen has not been previously studied. Aims of this study included determining the efficacy of the block, investigating whether any region (labial mucosa, alveolar mucosa, or teeth) was more reliably anesthetized, and if differences in efficacy existed between bilateral and unilateral blocks. In this blinded trial, 10 horses each were randomly assigned to receive a left uni...
A dominant missense variant within LMBR1 related to equine polydactyly. Polydactyly was recorded before 100 BCE and attracted widespread interest because of its relationship to limb health and ancestral traits in horses. However, the underlying reasons for the development of polydactyly remain unclear. To search for polydactyly-related genes, we utilize a paternal half-sib family and screen for variants that match the mode of inheritance. Through this screening process, 77 variants in 65 genes are filtered. A missense variant (EqCab3.0 chr4: <107353368> A > G) (rs1138485164) in the 3rd exon of LMBR1 is identified as a source of amino acid sequence variatio...
Oxygen consumption, locomotory-respiratory coupling and exercise-induced pulmonary hemorrhage in horses during the Paso Fino gait. Workload associated with the high frequency Colombian Paso Fino gait has not been evaluated. Objective: To determine the oxygen consumption (V̇O), heart rate (HR), stride frequency: breathing ratio, and hematology associated with the Paso Fino gait, including whether exercise-induced pulmonary hemorrhage (EIPH) occurs. Methods: Eleven Paso Fino horses. Methods: Prospective cohort study. Horses performed a standardized Paso Fino gait test across a wooden sounding board, simulating competition. V̇O and ventilatory parameters (tidal volume [V]; peak inspiratory and expiratory airflows [PkV̇, P...
Sub-Tenon’s anesthesia in equine cataract surgery and vitrectomy: a retrospective case series (2018-2022). A retrospective data analysis was performed on 17 eyes from 13 horses which underwent a sub-Tenon's injection to facilitate phacoemulsification or pars plana vitrectomy under general anesthesia between 2018 and 2022. All procedures were performed by the same veterinary ophthalmologist. Seven eyes received a sub-Tenon's dose of 7 ml lidocaine (XylocainÒ, 2 % lidocaine hydrochloride, Germany, Aspen Germany GmbH), and 10 eyes received 7 ml mepivacaine (MepinaestÒ purum 2 %, mepivacaine hydrochloride, Switzerland, Gebro Pharma GmbH). Statistical analysis compared onset and duration of gl...
Retrospective evaluation of the impact of atropine administration on incidence of post-operative colic in healthy, isoflurane-anaesthetised horses. In anaesthetised horses, bradycardia secondary to high vagal tone can reduce cardiac output and blood pressure. The use of anticholinergics in horses is limited due to concerns about ileus and abdominal discomfort. This retrospective study sought to determine the prevalence of post-operative abdominal discomfort in healthy horses that received atropine under isoflurane anaesthesia. Methods: A retrospective evaluation of 222 general anaesthesia events between January 2019 and December 2019 was undertaken. Methods: One hundred and eleven horses that received atropine were identified, and 111 cas...
Decreased Circulating Red Cell Mass Induced by Intravenous Acepromazine Administration Alters Viscoelastic and Traditional Plasma Coagulation Testing Results in Healthy Horses. Coagulopathy is common in equine critical illness, with its early recognition being crucial for patient management and prognosis. In vitro viscoelastic (VE) hypercoagulability with decreased RCM/PCV has been demonstrated in dogs but not horses. Our objective was to evaluate the effects of acepromazine-induced (0.1 mg/kg IV) decreased RCM on VE and plasma coagulation parameters using a prospective interventional study of eight adult horses. Complete blood count (CBC), fibrinogen, prothrombin time (PT), partial thromboplastin time (PTT), packed cell volume (PCV), total solids (TS), and VCM Vet...
Intake, digestibility, and behavior of horses fed açaí kernel (Euterpe oleracea Mart.) as a substitute of Mombaça grass (Megathyrsus maximus). In this study, we analyzed the effects of including açaí kernel, in the experimental diets fed to horses on the intake and digestibility of their nutrient and the resultant effects on the behavior of horses. The experiments were conducted in Federal Rural University of Amazonia. Five mares with no defined breeds, were allocated to five treatments (the replacement of Mombaça grass (Megathyrsus maximus) with crushed açaí kernel at 0, 18.75, 37.50, 56.25, and 75% levels of dry matter), in a 5 × 5 Latin square design. The animals were housed in covered stalls with concrete floors, equipp...
Improvement of gastric disease and ridden horse pain ethogram scores with diet adaptation in sport horses. Gastric disease is highly prevalent in sport horses and may lead to poor performance, cause behavioral changes and impact welfare. Objective: Assess whether diet affects gastric disease and pain expression during riding, and whether it has an impact on physiological and locomotor variables during an exercise test, including jumps. Methods: Nine healthy show-jumping Warmbloods trained at the same stable. Methods: Prospective observational cohort study. The horses receiving a pelleted diet, high in sugar and starch (>30%), were examined at T0 and after 12 weeks (T12) of changing to a cooked, m...
Comparison of a customized glycemic pellets challenge with the oral sugar test to measure glycemic and insulinemic responses in horses. Testing for insulin dysregulation (ID) in horses is commonly performed to guide management and therapeutic strategies. Objective: To evaluate a newly developed glycemic pellets challenge (GPC) and compare results to those obtained using the low-dose oral sugar test (OST). Methods: Twenty-four adult horses with unknown insulin status. Methods: A randomized crossover trial was performed. Horses underwent GPC (0.5 g glycemic carbohydrates/kg body weight) and OST (0.15 mL corn syrup/kg body weight) 7 days apart. Feed was withheld before testing and blood samples were collected at T0, T60, T1...
Ocular toxicity, distribution, and shedding of intravitreal AAV-eqIL-10 in horses. Non-infectious uveitis (NIU) is a painful recurrent disease affecting 2%-5% of horses. Current treatments require frequent administration with associated adverse events. In a previous study, intravitreal (IVT) adeno-associated virus (AAV) harboring equine interleukin-10 (eqIL-10) cDNA inhibited experimental uveitis in rats. The goal of this study was to evaluate the ocular tolerability, vector genome (vg) distribution, and vector shedding following an IVT injection of AAV8-eqIL-10 in normal horses with the hypothesis that it would be well tolerated in a dose-dependent manner in horses. Inject...
A wearable real-time particulate monitor demonstrates that soaking hay reduces dust exposure. Affordable particulate matter (PM) monitors suitable for use on horses will facilitate the evaluation of PM mitigation methods and improve the management of equine asthma. Objective: Calibrate a real-time wearable PM monitor (Black Beauty [BB]) and compare the PM exposures of horses fed dry or soaked hay. Methods: Laboratory calibration; complete cross-over feed trial. Methods: Side-by-side sampling with BB monitors and tapered element oscillating microbalances (TEOMs) was performed under varying concentrations of PM from alfalfa hay. Linear regression was used to derive a calibration formula ...
Gross Anatomy of the Equine Masseter Muscle: Lamination and Intramuscular Course of the N. Massetericus. The masticatory muscles of the horse are arranged in an asymmetrical pattern. Four individual muscles on the medial side of the mandible are opposed by one muscle (M. masseter) on the lateral side. However, recent studies on various herbivorous mammals indicate that the masseter muscle features a complex stratigraphic structure that might account for a functional diversity resembling an arrangement of several individual muscles. The functional consideration of the multidirectional equine masticatory movements leads to a similar hypothesis. In order to elucidate the detailed anatomy of the equi...
Pneumocephalus due to temporohyoid osteoarthropathy in a 16-year-old Friesian mare. A sixteen-year-old Friesian mare was admitted to the university clinic with the following clinical signs: anorexia, weight loss, fever, bilateral nasal discharge, unilateral facial paralysis and a non-healing corneal lesion. Endoscopic examination of the upper airways showed thickening of the proximal portion of the right stylohyoid bone. Computed tomography imaging showed pneumocephalus due to grade 3 unilateral temporohyoid osteoarthropathy (THO) with fracture of the petrous temporal bone. The horse did not improve following medical treatment. Surgical intervention was declined by the owner ...
A first step towards objective grading of equine laryngeal function. Due to concerns about disagreement between veterinarians when grading resting laryngeal function (LF), a diagnostic decision tree (DDT) has been developed by codifying the Havemeyer grading system and objectively defining certain terms to remove ambiguity. Videoendoscopic examinations of the equine larynx that had previously been assigned a unanimous LF grade by 3 experienced observers were used to develop the DDT and determine the cut-off values. The DDT is a flow chart consisting of a series of dichotomous (yes/no) decisions, to dictate the order of decision making and direct the observer do...
Advancements in equine ophthalmic imaging enhance understanding of ocular and orbital anatomy and disease in standing sedated horses. To review data on the advances in equine ophthalmic imaging that have been made during the past 5 years and highlight advantages of using multiple imaging modalities to improve clinical observational skills and improve diagnostic accuracy. Methods: A literature review from 2019 through 2024 of equine ophthalmic digital photography, fundus photography, ocular and orbital ultrasonography (US), ultrasound biomicroscopy (UBM), confocal microscopy (CM), spectral domain optical coherence tomography (SD-OCT), radiography, CT, and MRI. Results: Digital photography remains the cornerstone of equine oph...
A systematic review of the prevalence of post-operative complications after general anaesthesia in adult horses (2000-2023). Equine post-operative morbidity represents a significant concern for both veterinary surgeons and horse owners. Objective: To estimate the prevalence of post-operative complications in horses after elective/non-abdominal surgery or colic surgery. Methods: Systematic review. Methods: A database search identified eligible studies which reported the prevalence of equine post-operative complications published as a full paper in English in a peer-reviewed journal between 2000 and 2023. Studies were evaluated using the JBI Critical Appraisal Checklist for Prevalence Studies and GRADE (Grading of Rec...
Influence of the Vertek aiming device on the surgical accuracy of computer-assisted drilling of the equine distal sesamoid bone-An experimental cadaveric study. To determine the effect of the Vertek aiming device (VAD) on the surgical accuracy of navigated drilling of the distal sesamoid bone (DSB). Methods: Experimental cadaveric study. Methods: A total of 30 paired equine cadaveric limbs from 15 horses. Methods: Each specimen was placed in a purpose-built frame (PBF). Preoperative cone beam computed tomography (CBCT) images were acquired with an imaging unit coupled with a surgical navigation system. In the DSB of each specimen, a 4.5 mm glide hole and a 3.2 mm thread hole were drilled under navigation guidance, to simulate drilling for the repa...
Influence of Loading Density and Gender on the Welfare and Meat Quality of Horses During Transport for Slaughter. The aim of this study was to determine the effects of loading density and gender on blood welfare indicators, carcass bruises and horsemeat quality. Data were collected from twelve transports of 89 slaughter horses originating from the same collection centre. The transportation of slaughter horses at high loading densities (>200 kg/m), especially stallions, resulted in increased levels of lactate ( = 0.021), glucose ( < 0.0001), ceruloplasmin ( < 0.0001) and AOPP ( < 0.0001), but lower GSH levels ( 200 kg/m) during transport had lower levels of the aforementioned blood metabolites....
Unravelling the speed-going relationship: A proof of concept study from British turf flat and jump race meetings. The maximum galloping speeds of racehorses during a race are influenced by the functional performance of the ground ('going') amongst other factors. For turf racecourses in Britain, the ground is descriptively classified and numerically quantified on the morning of a race meeting by the clerk of the course and subsequently published to assist decision making. Importantly, this includes deciding whether a horse should or should not run. The going is also assessed and classified during the meeting by racing analysts using the normalized winning times from each race result. Differences between go...
Influence of acepromazine on the cardiovascular effects of dobutamine in isoflurane-anaesthetised horses premedicated with romifidine. To explore the influence of acepromazine on the cardiovascular effects of dobutamine in isoflurane-anaesthetised horses premedicated with romifidine. Methods: Prospective randomised clinical trial. Methods: A total of 18 horses undergoing elective arthroscopy were enrolled, of which 12 horses requiring dobutamine were included. Methods: Horses were randomised to receive acepromazine 0.02 mg kg (Group A+) intravenously (IV) or none (Group A-), 35 minutes before anaesthesia. Horses received xylazine 0.2 mg kg concurrently to facilitate IV access. Horses were premedicated with romifidine 0.08 mg ...
Effect of furosemide on comprehensive renin-angiotensin-aldosterone system activity of Thoroughbred horses. Furosemide, a commonly used diuretic, activates the renin-angiotensin-aldosterone system (RAAS) in other species. Little is known about RAAS peptide activation in horses. Objective: To evaluate equilibrium analysis as a practical method for RAAS quantification in horses and describe the RAAS response to a single dose of furosemide. We hypothesize that furosemide would cause transient increase in RAAS peptides in horses. Methods: 14 healthy adult thoroughbreds from a university teaching herd. Methods: Horses received either furosemide (1 mg/kg IV) or saline IV in a crossover study design. Pro...
Assessment of equine intestinal epithelial junctional complexes and barrier permeability using a monolayer culture system. Gastrointestinal disease is a leading cause of death in mature horses. A lack of in vitro modeling has impeded the development of novel therapeutics. The objectives of this study were to develop and further characterize a small intestinal monolayer cell culture derived from equine jejunum including establishing normal measurements of intestinal permeability and restitution. Three-dimensional enteroids, derived from postmortem sampling of equine jejunum, were utilized to develop confluent epithelial monolayers. The presence of differentiated intestinal epithelial cell types and tight junctions ...
Periovulatory anticoagulant therapy enhances embryo recovery rates in superovulated mares. Although protocols for superovulation have been described in horses, this technique has been discouraged due to the low embryo recovery rates in superovulated mares. The reason for these poor results is poorly understood, but the formation of a blood clot in the ovulation fossa following ovulations has been hypothesized. Therefore, this study aimed to assess the safety and effect of periovulatory anticoagulant therapy on embryo recovery of superovulated mares. In experiment 1, five mares were assigned to receive five anticoagulant treatments in a crossover design: intravenous injections of 150...