Equine diseases encompass a wide range of health conditions that can affect horses, including infectious diseases, metabolic disorders, and genetic conditions. These diseases can impact the overall health, performance, and well-being of horses. Common equine diseases include equine influenza, equine herpesvirus, laminitis, and equine metabolic syndrome. Diagnosis and management of these diseases often require a combination of clinical evaluation, laboratory testing, and appropriate treatment strategies. This page gathers peer-reviewed research studies and scholarly articles that explore the etiology, pathophysiology, diagnosis, and treatment options for various equine diseases, providing valuable insights for veterinarians and researchers in the field.
Moorman VJ, Reiser RF, Mahaffey CA, Peterson ML, McIlwraith CW, Kawcak CE.To determine intralimb orientation changes with an inertial measurement unit (IMU) in hooves of horses at a walk and trot after induction of weight-bearing single forelimb lameness and to determine whether hoof orientations are similar to baseline values following perineural anesthesia. Methods: 6 clinically normal horses. Methods: 3-D hoof orientations were determined with an IMU mounted on the right forelimb hoof during baseline conditions, during 3 grades of lameness (induced by application of pressure to the sole), and after perineural anesthesia. Linear acceleration profiles were used to ...
Petersen JL, Valberg SJ, Mickelson JR, McCue ME.Two variants in the equine myostatin gene (MSTN), including a T/C SNP in the first intron and a 227-bp SINE insertion in the promoter, are associated with muscle fiber type proportions in the Quarter Horse (QH) and with the prediction of race distance propensity in the Thoroughbred (TB). Genotypes from these loci, along with 18 additional variants surrounding MSTN, were examined in 301 horses of 14 breeds to evaluate haplotype relationships and diversity. The C allele of intron 1 was found in 12 of 14 breeds at a frequency of 0.27; the SINE was observed in five breeds, but common in only the T...
Pascucci L, Alessandri G, Dall'Aglio C, Mercati F, Coliolo P, Bazzucchi C, Dante S, Petrini S, Curina G, Ceccarelli P.Multipotent mesenchymal stromal cells (MSCs) have attracted a great deal of interest, due to several distinctive features, including the ability to migrate to damaged tissue and to participate in tissue regeneration. There is increasing evidence that membrane vesicles (MVs), comprising exosomes and shedding vesicles, represent a key component, responsible for many of the paracrine effects of MSCs. The aim of the present study was to establish whether equine adipose-derived MSCs (E-AdMSCs) produce MVs that are capable of influencing angiogenesis, a key step in tissue regeneration. A morphologic...
Boeer U, Buettner FF, Klingenberg M, Antonopoulos GC, Meyer H, Haverich A, Wilhelmi M.The limited biocompatibility of decellularized scaffolds is an ongoing challenge in tissue engineering. Here, we demonstrate the residual immunogenicity of an extensively decellularized equine carotid artery (dEAC(intens)) and identify the involved immunogenic components. EAC were submitted to an elaborated intensified decellularization protocol with SDS/sodium desoxycholate for 72 h using increased processing volumes (dEAC(intens)), and compared to dEAC(ord) prepared by an ordinary protocol (40 h, normal volumes). Matrix integrity was checked via correlative volumetric visualization which rev...
Bordin AI, Pillai SD, Brake C, Bagley KB, Bourquin JR, Coleman M, Oliveira FN, Mwangi W, McMurray DN, Love CC, Felippe MJ, Cohen ND.Rhodococcus equi is an important pathogen of foals that causes severe pneumonia. To date, there is no licensed vaccine effective against R. equi pneumonia of foals. The objectives of our study were to develop an electron beam (eBeam) inactivated vaccine against R. equi and evaluate its immunogenicity. A dose of eBeam irradiation that inactivated replication of R. equi while maintaining outer cell wall integrity was identified. Enteral administration of eBeam inactivated R. equi increased interferon-γ production by peripheral blood mononuclear cells in response to stimulation with virulent R. ...
Dong J, Cook FR, Haga T, Horii Y, Norimine J, Misawa N, Goto Y, Zhu W.Although equine infectious anemia virus (EIAV) poses a major threat to the equine industry worldwide, the molecular epidemiology of this virus is poorly understood. Recently, an EIAV strain (EIAVMiyazaki2011-A) representing a new monophyletic group was discovered in feral horses in southern Japan. In the present study, the EIAVMiyazaki2011-A proviral genome is compared with evolutionarily divergent EIAV isolates to investigate conservation of functional elements or motifs within the long terminal repeats (LTRs) and structural genes. This analysis represents a significant step forward in increa...
Sykes BW, Sykes KM, Hallowell GD.Interest in Equine Gastric Ulcer Syndrome (EGUS) has recently increased in part due to a growing awareness of the differences between squamous and glandular disease. The pathophysiology and epidemiology of squamous and glandular disease are different and recently it has been shown that the response of glandular gastric ulceration to monotherapy with omeprazole is poor. Given these differences it has been recommended that specific treatment guidelines be formulated for equine glandular disease and that adjunctive therapies be investigated. Along these lines it has been suggested that the additi...
Lyons ET, Tolliver SC.The prevalence of patent Strongyloides westeri infections was determined by examination for eggs in fecal samples collected from 513 Thoroughbred (TB) foals between February 25 and June 3, 2014. The study was conducted with 244 colts and 269 fillies from 11 well-managed farms in Central Kentucky. Foals ranged from 17 to 117 days of age and had never been dewormed. The mean prevalence of patent S. westeri infection was 30% (156/513 foals). This prevalence was substantially greater than historical reports from the same sampling area during the late 1990s and early 2000s. It is hypothesized that ...
Fernandez-Fuente M, Terracciano CM, Martin-Duque P, Brown SC, Vassaux G, Piercy RJ.Dysfunctional skeletal muscle calcium homeostasis plays a central role in the pathophysiology of several human and animal skeletal muscle disorders, in particular, genetic disorders associated with ryanodine receptor 1 (RYR1) mutations, such as malignant hyperthermia, central core disease, multiminicore disease and certain centronuclear myopathies. In addition, aberrant skeletal muscle calcium handling is believed to play a pivotal role in the highly prevalent disorder of Thoroughbred racehorses, known as Recurrent Exertional Rhabdomyolysis. Traditionally, such defects were studied in human an...
Dubuc J, Lavoie JP.The objective of this study was to determine whether eosinophils infiltrate the airway wall of horses with heaves. Eosinophils were evaluated using paraffin embedded lung tissues from six heaves-affected horses in crisis and six aged-matched controls. Slides were stained using Luna's method and eosinophils enumerated using histomorphometric techniques. Total eosinophil counts (expressed per mm(2) of basement membrane) were significantly higher in the airways of controls horses than in horses with heaves. Intraluminal, intraepithelial, and airway smooth muscle eosinophils counts were also incre...
Sano Y, Matsuda K, Osaki K, Miyasho T, Tsuda T, Taniyama H.A male Thoroughbred fetus was aborted on day 251 of pregnancy. Gross and histological examinations detected systemic granulomatous lesions in many superficial and visceral lymph nodes and organs including the liver, tonsils, lungs, thymus, spleen, right thyroid gland and gastrointestinal tract, and suppurative placentitis, pyogranulomatous amnionitis and intralesional acid-fast bacilli were also detected. An examination of the DNA base sequence of the β subunit of RNA polymerase demonstrated that Mycobacterium avium strain 104 had infected several organs. To the best of our knowledge, this is...
Morrell JM, Johannisson A.The effect on sperm motility and chromatin integrity of adding homologous or heterologous equine seminal plasma (SP) to fresh stallion spermatozoa selected by single layer centrifugation (SLC) was studied. No statistical difference in mean progressive motility was seen after adding SP at time 0 h, although there were differences for individual stallions. The proportion of spermatozoa with high velocity was increased compared to untreated SLC-selected spermatozoa (P < 0.05), with significant differences between individuals (P < 0.01). When the SLC samples were stored for 24 h before a...
Nemoto M, Oue Y, Morita Y, Kanno T, Kinoshita Y, Niwa H, Ueno T, Katayama Y, Bannai H, Tsujimura K, Yamanaka T, Kondo T.Recently, outbreaks associated with equine coronavirus (ECoV) have occurred in Japan and the United States. While ECoV is likely to be pathogenic to horses, it has not been shown that experimental inoculation of horses with ECoV produces clinical signs of disease. In this study, we inoculated three Japanese draft horses with an ECoV-positive diarrheic fecal sample to confirm infection after inoculation and to investigate the clinical course and virus shedding patterns of ECoV. Virus neutralization tests showed that all three horses became infected with ECoV. Two of the three horses developed c...
Leise BS, Watts MR, Roy S, Yilmaz AS, Alder H, Belknap JK.Dysadhesion of laminar basal epithelial cells (LBECs) from the underlying dermis is the central event leading to structural failure in equine laminitis. Although many studies of sepsis-related laminitis have reported multiple events occurring throughout the lamellar tissue, there is minimal information regarding signalling events occurring specifically in LBECs. Objective: To determine signalling events in the LBECs during the early stages of carbohydrate-induced laminitis. Methods: Experimental study. Methods: Eight horses were given an overload of carbohydrate (CHO) consisting of corn starch...
Manso-Díaz G, Dyson SJ, Dennis R, García-López JM, Biggi M, García-Real MI, San Román F, Taeymans O.The equine head is an anatomically complex area, therefore advanced tomographic imaging techniques, such as computed tomography or magnetic resonance imaging (MRI), are often required for diagnosis and treatment planning. The purpose of this multicenter retrospective study was to describe MRI characteristics for a large sample of horses with head disorders. Horses imaged over a period of 13 years were recruited. Eighty-four horses met the inclusion criteria, having neurological (n = 65), sinonasal (n = 14), and soft tissue (n = 5) disorders. Magnetic resonance imaging accurately depicted the a...
Ilginis T, Clarke J, Patel PJ.The last two decades have seen a revolution in ophthalmic imaging. In this review we present an overview of the breadth of ophthalmic imaging modalities in use today and describe how the role of ophthalmic imaging has changed from documenting abnormalities visible on clinical examination to the detection of clinically silent abnormalities which can lead to an earlier and more precise diagnosis. Methods: This review is based on published literature in the fields of ophthalmic imaging and with focus on most commonly used imaging modalities. Results: New imaging techniques enable non-invasive eva...
Burton AJ, Giguère S, Arnold RD.Although gentamicin is highly active against Rhodococcus equi in vitro, its clinical efficacy has been limited presumably due to poor cellular uptake. Encapsulation of drugs in liposomes enhances their cellular uptake. Objective: To compare the disposition of liposomal gentamicin (LG) and free gentamicin (FG) in the plasma, pulmonary epithelial lining fluid and bronchoalveolar cells of healthy foals after i.v. administration or by nebulisation, and to assess the tolerability of the drug after repeated i.v. dosing. Methods: Experimental study. Methods: Eight healthy foals received a single i.v....
Donnelly KS, Giuliano EA, Sharm A, Mohan RR.To explore the effect of suberoylanilide hydroxamic acid (SAHA) (i) on corneal fibroblast differentiation, morphology, and viability; and (ii) on the expression levels of matrix metalloproteinases (MMPs) 2 and 9 using an in vitro model of equine corneal fibrosis. Methods: Healthy donor corneas were used to generate primary cultures of equine corneal fibroblasts. The fibroblasts were exposed to 5 ng/mL TGFβ1 to induce myofibroblast formation. The cultures were treated with either 5 μm or 10 μm SAHA for 72 h in the presence of TGFβ1. Real-time PCR and immunocytochemistry were used to determi...
Giuliano EA, Johnson PJ, Delgado C, Pearce JW, Moore CP.(i) To report the successful treatment of 10 cases of equine periocular squamous cell carcinoma (PSCC) with surgical excision and photodynamic therapy (PDT) using verteporfin. (ii) To evaluate time to first tumor recurrence between PDT-treated horses and horses treated with surgical excision and cryotherapy. Methods: A total of 24 equine PSCC cases were included: group 1 (n = 14) had excision and cryotherapy (1993–2003), group 2 (n = 10), excision and local PDT (2006–2010). Evaluated data: signalment, treatment method, tumor location, size, and time to first recurrence. Groups were compare...
Hempstead JE, Clode AB, Borst LB, Gilger BC.To evaluate corneal changes associated with chronic, nonhealing, superficial, corneal ulcers in horses via common histopathological stains. Methods: Retrospective study. Methods: Twenty-four horses diagnosed with chronic, nonhealing, superficial, corneal ulceration. Methods: The medical records of horses evaluated at North Carolina State University's Veterinary Teaching Hospital (NCSU-VTH) from 2005 to 2011, diagnosed with a chronic, nonhealing, superficial, corneal ulcer and treated with superficial keratectomy (SK) were reviewed. Inclusion criteria were superficial corneal ulceration, no cel...
Greve L, Dyson S.No previous studies have investigated interrelationships between saddle fit/management, equine thoracolumbar asymmetries, rider and horse health. Objective: To assess associations between data obtained by clinical assessment and those provided by riders via a questionnaire. Methods: Clinical assessment of a convenience sample of horses and riders compared with a Web-based questionnaire survey (n = 205). Methods: Horse thoracolumbar asymmetries at predetermined sites, the presence of lameness (in hand and/or ridden), saddle slip, saddle fit/management and rider straightness were assessed. Kappa...
Sobczak N, Kantyka M.The saliva of medicinal leeches, e.g., Hirudo medicinalis and Hirudo verbana commonly used in hirudotherapy, contains more than 100 bioactive substances with various therapeutic effects, including anticoagulant, vasodilator, thrombolytic, anti-inflammatory and anaesthetic properties. Recently, leeches have been used very successfully in veterinary medicine to treat many diseases of animals, especially dogs, cats and horses. The most common indications for the use of leeches are hip and elbow dysplasia, acute and chronic arthritis, diseases associated with inflammation of tendons, ligaments, an...
Franke J, Abraham G.Altered airway cell proliferation plays an important role in the pathogenesis of human bronchial asthma and chronic obstructive pulmonary disease (COPD) as well as the equine recurrent airway obstruction (RAO) with consistent changes, i.e. narrowing the airway wall, explained by proliferation and differentiation of fibroblasts. In permanent cell lines, it has been suggested that β2-adrenoceptor agonists and glucocorticoids regulate cell proliferation via the β2-adrenoceptor pathway; indeed, no study was carried out in fresh isolated primary equine bronchial fibroblasts (EBF). We characterize...
Walker RL, Runyan CA.To determine whether previously unidentified variations of the SzP protein of Streptococcus equi subsp zooepidemicus were present in horses with various clinical signs of infection and whether any relationship could be identified between SzP protein variants and naturally occurring clinical conditions. Methods: 23 isolates of S equi subsp zooepidemicus were recovered from specimens of horses with various clinical conditions and used as a representative population of isolates for evaluation of different SzP protein variants. Methods: Genetic heterogeneity of the isolates was demonstrated by rep...
Yamashita-Kawanishi N, Chambers JK, Uchida K, Tobari Y, Yoshimura H, Yamamoto M, Yumoto N, Aoki H, Sugiura K, Higuchi T, Saito S, Haga T.Bovine papillomavirus types 1 and 2 (BPV1/2) infection in horses has been associated with the development of equine sarcoids. Previous findings revealed the presence of sarcoid-associated BPV sequence variants that have been proposed as a key factor of cross-species infection in horses. To verify this hypothesis, sarcoid-associated BPV variants should be identified regardless of geographic location. Objective: Sequence analyses of BPV1/2 derived from both horses and cattle were conducted to clarify the sarcoid-associated sequence variants. The aim of this study was to clarify the correlation b...
Allen GP, Yeargan MR, Turtinen LW, Bryans JT.From restriction endonuclease characterization of the DNA of 317 isolates of equine abortion virus (equine herpesvirus-1; EHV-1) from 176 epizootically unrelated outbreaks of equine virus abortion occurring over 24 years in Kentucky, an epizootic pattern and variation of the virus have emerged. Two electropherotypes of EHV-1 (1P and 1B) accounted for greater than 90% of the nonvaccine-related abortion isolates examined. From 1960 to 1981, EHV-1 1P was the predominant isolate circulating in the central Kentucky area and the cause of greater than 80% of EHV-1-related abortions. In 1981, the occu...
Donoghue EM, Lyons ET, Bellaw JL, Nielsen MK.Parascaris spp. infects foals worldwide and may cause airway inflammation in addition to small intestinal impaction and rupture. It is observed that acquired immunity eliminates ascarid burdens beginning at about 6 months of age, and current evidence suggests that a single parasite generation propagates in each foal crop. The purpose of this study was to monitor natural parasitic infections in untreated mixed breed horse foals over the course of 0-300 days of age. Fecal samples were collected monthly from all foals born in 2014 (n=13), beginning July 2014 through February 2015. Fecal egg count...
Oki H, Miyake T, Kasashima Y, Sasaki Y.The superficial digital flexor tendon (SDFT) injury causes considerable wastage of racing Thoroughbreds. In this study, the heritability of SDFT injury of the forelimbs was estimated in the Thoroughbred racehorses based on the Bayesian analysis with Gibbs sampling using threshold animal models. New horse patients of SDFT injury at the age of 2-5 years accommodated in the training centers in 2005 were used for the analyses. Based on clinical data of 8198 horses, heritability of SDFT was estimated to be the order of 0.17 (posterior mode) to 0.19 +/- 0.05 (posterior mean +/- posterior SD).
Foote CE, Love DN, Gilkerson JR, Whalley JM.Equine herpesvirus 1 (EHV-1) is a major cause of respiratory disease and abortion in horses worldwide. Although some vaccines have been shown experimentally to reduce disease, there are few reports of the responses to vaccination in the field. This study measured antibody responses to vaccination of 159 mares (aged 4-17 years) and 101 foals (aged 3-6 months) on a large stud farm with a killed whole virus EHV-1/4 vaccine used as per the manufacturer's recommendations. Using an EHV glycoprotein D (gD)-specific ELISA and a type-specific glycoprotein G (gG) ELISA, respectively 13.8 and 28.9% of ma...
Calisher CH, Oro JG, Lord RD, Sabattini MS, Karabatsos N.A virus isolated from the blood of a febrile horse in Argentina was identified as a strain of Kairi virus. This is the fifth Bunyamwera serogroup virus isolated from livestock and wild animals in the Americas. Bunyamwera serogroup viruses have been isolated from febrile humans in the Americas and Africa.
Brooks MB.The most common cause of hemorrhage is vascular injury; however, the possibility of hemostatic failure should be considered in the initial differential diagnosis. This article provides an overview of preliminary screening and definitive tests to identify hemostatic defects in horses.
Menzies-Gow NJ.Certain individual animals appear predisposed to recurrent pasture-associated laminitis, but the exact mechanisms underlying their predisposition remain a fundamental question in laminitis research. The risk of endocrinopathic laminitis can be reduced if steps are taken to improve insulin sensitivity and reduce inflammation using strategies based on exercise and diet. Exercise has been shown to reduce insulin resistance and suppress inflammation, and dietary manipulation can significantly affect insulin sensitivity.
Winther L, Guardabassi L, Baptiste KE, Friis C.Sulfadiazine (SDZ) and trimethoprim (TMP) concentrations were examined in plasma and pulmonary epithelial lining fluid (PELF), following intravenous and oral administration and compared to minimum inhibitory concentrations (MICs) of common bacterial isolates from equine lower airway infections. SDZ/TMP (25/5 mg/kg) was administered intravenously, intragastric or per os to fed horses, and blood samples were collected before and 11 times, over 24 h, after administration. PELF samples were collected via a tampon device four times after drug administration and analysed for drug concentrations. Add...
Burns TA, Watts MR, Weber PS, McCutcheon LJ, Geor RJ, Belknap JK.Acute, massive enteral carbohydrate overload is associated with laminar inflammation in equids; it is unclear if the same is true for a more prolonged period of moderate dietary carbohydrate intake. Objective: To characterise laminar inflammation in ponies exposed to a dietary carbohydrate challenge meant to mimic acute pasture exposure. Methods: In vivo experiment. Methods: Mixed-breed ponies (n = 22) received a diet of hay chop (nonstructural carbohydrate [NSC] ∼7% on a dry matter [DM] basis) for 4 weeks prior to initiation of the experimental feeding protocol. Following dietary acclimatio...
Rodríguez MJ, Soler M, Latorre R, Gil F, Agut A.The objective was to describe the normal ultrasonographic appearance of the soft tissue and bony structures of the temporomandibular joint in Pure-Bred Spanish horses using frozen and plastinated sections performed as anatomical references. The temporomandibular joint of five healthy Pure-Bred Spanish horses and the head specimens from 12 Pure-Bred Spanish cadavers that were subjected to euthanasia for reasons other than temporomandibular joint problems were studied sonographically and anatomically. An 11 MHz linear-array transducer was used to obtain longitudinal ultrasonographic images of th...
Aho R, Tala M, Kivalo M.The first identified Finnish case of equine mycotic keratitis caused by Aspergillus fumigatus is described. The clinical picture, the sampling method, the macro- and micromorphology of the causative fungus and the therapy applied are reported in detail. Therapy with natamycin (Pimafucin 2.5% eyedrops. Gist-Brocades) was successful. Mykotisk keratit hos häst orsakad av beskrivs första gången i Finland. Klinisk bild, provtagning, makroskopisk och mikroskopisk morfologi av svampen samt terapi rapporteras i detalj. Terapin med natamycin (Pimafucin® 2.5 % ögondroppar, Gist-Brocades) var effek...
Rijckaert J, Pardon B, Saey V, Raes E, Van Ham L, Ducatelle R, van Loon G, Deprez P.Transcranial magnetic stimulation (TMS) and recording of magnetic motor evoked potentials (MMEP) can detect neurological dysfunction in horses but cutoff values based on confirmed spinal cord dysfunction are lacking. Objective: To determine latency time cutoff for neurological dysfunction. Methods: Five control horses and 17 horses with proprioceptive ataxia. Methods: Case-control study with receiver operating characteristic curve analysis, based on diagnostic imaging, TMS, and histopathological findings. Horses were included if all 3 examinations were performed. Results: Diagnostic imaging an...
Byam-Cook KL, Henson FM, Slater JD.Treatment of the equine sarcoid has posed a significant challenge to clinicians for years and many different methods have been tried with varying success, including ionising radiation. The aim of this study was to review the efficacy of iridium-192 interstitial brachytherapy for the treatment of eight periocular sarcoids and 15 non-ocular sarcoids on 18 horses. All the periocular sarcoids and 13 of the 15 non-ocular sarcoids were treated successfully.
Pellegrini-Masini A, Livesey LC.This article provides an overview of meningitis and encephalomyelitis in horses, including diagnostic tests, treatment developments, and preventative measures reported in the equine and human medical literature of the past few years.
Daglish J, Mama KR.This article provides a brief overview of pain physiology and its relevance to equine patients. Objective and subjective techniques for assessing pain in the horse are described in depth. Pharmacologic and interventional pain modulation treatments are discussed with a focus on the rehabilitating horse.