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.
Harland MM, Stewart AJ, Marshall AE, Belknap EB.Deafness was confirmed in a blue-eyed, 3-year-old, overo paint horse by brainstem auditory evoked potential. Congenital inherited deafness associated with lack of facial pigmentation was suspected. Assessment of hearing should be considered, especially in paint horses, at the time of pre-purchase examination. Brainstem auditory evoked potential assessment is well tolerated and accurate. Un diagnostic de surdité a été confirmé par potentiel auditif évoqué au niveau du tronc cérébral chez un cheval Paint Horse overo aux yeux bleus âgé de 3 ans. Une surdité congénitale héréditaire ...
Bischofberger AS, Ringer SK, Geyer H, Imboden I, Ueltschi G, Lischer CJ.To determine via histologic examination and scintigraphy the effect of focused extracorporeal shock wave therapy (ESWT) on normal bone and the bone-ligament interface in horses. Methods: 6 horses without lameness. Methods: Origins of the suspensory ligament at the metacarpus (35-mm probe depth) and fourth metatarsal bone (5-mm probe depth) were treated twice (days 0 and 16) with 2,000 shocks (energy flux density, 0.15 mJ/mm2). One forelimb and 1 hind limb were randomly treated, and the contralateral limbs served as nontreated controls. Bone scans were performed on days -1 (before ESWT), 3, 16,...
Sabeur K, Ball BA.To identify the generation of the superoxide anion by equine spermatozoa. Methods: Multiple ejaculates collected from 3 Thoroughbred stallions. Methods: Induced superoxide production by reduced nicotinamide adenine dinucleotides (NAD[P]H; ie, reduced nicotinamide adenine dinucleotide [NADH] and reduced nicotinamide adenine dinucleotide phosphate [NADPH]) was measured by use of a nitroblue tetrazolium (NBT) reduction assay on whole spermatozoa and a cytochrome c reduction assay on isolated membrane fractions of spermatozoa. Localization of superoxide generation was determined by use of NBT cyto...
Stockton KA, Morley PS, Hyatt DR, Burgess BA, Patterson G, Dunowska M, Lee DE.To evaluate the effects of footwear hygiene protocols on bacterial contamination of floor surfaces in an equine hospital. Methods: Field trial. Methods: Footwear hygiene protocols evaluated included use of rubber overboots with footbaths and footmats containing a quaternary ammonium disinfectant, rubber overboots with footbaths and footmats containing a peroxygen disinfectant, and no restrictions on footwear type but mandatory use of footbaths and footmats containing a peroxygen disinfectant. Nonspecific aerobic bacterial counts were determined via 2 procedures for sample collection and bacter...
Perrocheau M, Boutreux V, Chadi S, Mata X, Decaunes P, Raudsepp T, Durkin K, Incarnato D, Iannuzzi L, Lear TL, Hirota K, Hasegawa T, Zhu B, de Jong P....A medium-density map of the horse genome (Equus caballus) was constructed using genes evenly distributed over the human genome. Three hundred and twenty-three exonic primer pairs were used to screen the INRA and the CHORI-241 equine BAC libraries by polymerase chain reaction and by filter hybridization respectively. Two hundred and thirty-seven BACs containing equine gene orthologues, confirmed by sequencing, were isolated. The BACs were localized to horse chromosomes by fluorescent in situ hybridization (FISH). Overall, 165 genes were assigned to the equine genomic map by radiation hybrid (RH...
Minke JM, Fischer L, Baudu P, Guigal PM, Sindle T, Mumford JA, Audonnet JC.In this study, experimental canarypox virus (ALVAC) and plasmid DNA recombinant vaccines expressing the gB, gC and gD glycoproteins of EHV-1 were assessed for their ability to protect conventional ponies against a respiratory challenge with EHV-1. In addition, potential means of enhancing serological responses in horses to ALVAC and DNA vaccination were explored. These included co-administration of the antigen with conventional adjuvants, complexation with DMRIE-DOPE and co-expression of the antigen along with equine GM-CSF. Groups of EHV primed ponies were vaccinated twice intra-muscularly wi...
Podolsky MJ, Lasker A, Flaminio MJ, Gowda LD, Ezekowitz RA, Takahashi K.The mannose-binding lectin (MBL), a pattern recognition serum protein, participates in the innate immune system of mammals as an opsonin. In humans, MBL plays a key role in first-line host defense against infection during the lag period prior to the development of a specific immune response. MBL also activates complement via the lectin pathway that requires a MBL-associated serine protease-2 (MASP-2). Homologues of human MBL (hMBL) have been identified in a variety of mammals, fish, and primitive animals such as ascidians. In this study, we report that equine MBL (eMBL) has properties that are...
Valentine BA.A retrospective study examined data regarding equine cutaneous and mucocutaneous neoplasms submitted to the Veterinary Diagnostic Laboratory at Oregon State University in a 3.5-year period. A total of 536 neoplasms were identified, accounting for 30% of the total equine pathology submissions. Sarcoid, squamous cell carcinoma, melanocytic tumors, papillomas, and mast cell tumors were the most common neoplasms, constituting 87.5% of all cutaneous neoplasms. Sarcoids represented 51.4% of all neoplasms and 15.18% of total equine accessions. Sarcoid was most common in paints, quarter horses, and Ar...
Pusterla N, Madigan JE.The U.C. Davis Large Animal Lift (LAL) is a lightweight sling developed to help lift horses in clinical and rescue situations. Here we report on its first use in 16 recumbent horses with neurologic, muscular and musculoskeletal disorders. For each horse, history, sedation, ease and time of LAL application and hoisting, standing ability, LAL tolerance and outcome were recorded. The LAL was easily and safely applied in all horses in less than five minutes and the procedure was well tolerated with minimal to no sedation. While 10 horses were able to stand in the LAL after being hoisted, 6 horses ...
Stewart AA, Rush B, Davis E.To document the efficacy of intratumoural injections of 5-fluorouracil for the treatment of equine sarcoids. Methods: A prospective study that included 13 horses and one donkey. Methods: Sarcoids were confirmed by histological examination and treated with intratumoural 5-fluorouracil every 2 weeks. If the sarcoids did not resolve after seven treatments, treatment was considered a failure. All cases were re-examined 6 months after treatment commenced and owners were telephoned 3 years after commencement of treatment to report on tumour recurrence. Outcome comparisons were performed to determine...
Wongaumnuaykul S, Siedler C, Schobesberger H, Stanek C.The aim of this study was to evaluate the use of Doppler ultrasonography to monitor vascular blood flow dynamics in defined diseases of the equine digit in a noninvasive way. Doppler sonography was used to evaluate medial digital artery blood flow in eight horses with septic pododermatitis and four horses with laminitis in comparison with 10 horses of a control group. Doppler sonographic measurement and lameness examinations were performed in lame horses before treatment (day 0) and at 3, 6, and 9 days following treatment. Before treatment, blood flow velocities, arterial diameter, and flow vo...
Shahar R, Zaslansky P, Barak M, Friesem AA, Currey JD, Weiner S.Young's modulus and Poisson's ratios of 6mm-sized cubes of equine cortical bone were measured in compression using a micro-mechanical loading device. Surface displacements were determined by electronic speckle pattern-correlation interferometry. This method allows for non-destructive testing of very small samples in water. Analyses of standard materials showed that the method is accurate and precise for determining both Young's modulus and Poisson's ratio. Material properties were determined concurrently in three orthogonal anatomic directions (axial, radial and transverse). Young's modulus va...
Yang J, Ellison S, Gogal R, Norton H, Lindsay DS, Andrews F, Ward D, Witonsky S.Equine protozoal myeloencephalitis (EPM) is one of the most common neurologic diseases of horses in the United States. The primary etiologic agent is Sarcocystis neurona. Currently, there is limited knowledge regarding the protective or pathophysiologic immune response to S. neurona infection or the subsequent development of EPM. The objectives of this study were to determine whether S. neurona infected horses with clinical signs of EPM had altered or suppressed immune responses compared to neurologically normal horses and if blood sample storage would influence these findings. Twenty clinical...
Lu J, Guo Z, Pan X, Wang G, Zhang D, Li Y, Tan B, Ouyang L, Yu X.Avian influenza virus H5N1 has demonstrated considerable pandemic potential. Currently, no effective vaccines for H5N1 infection are available, so passive immunotherapy may be an alternative strategy. To investigate the possible therapeutic effect of antibody against highly pathogenic H5N1 virus on a mammal host, we prepared specific equine anti-H5N1 IgGs from horses vaccinated with inactivated H5N1 virus, and then obtained the F(ab')2 fragments by pepsin digestion of IgGs. Methods: The horses were vaccinated with inactivated H5N1 vaccine to prepare anti-H5N1 IgGs. The F(ab')2 fragments were p...
Venugopal CS, Polikepahad S, Holmes EP, Heuvel JV, Leas TL, Moore RM.The purpose of this study was to evaluate the role of endothelin-1 (ET-1) and its receptors in the airway hyperreactivity of horses with obstructive pulmonary disease associated with summer pasture (SPAOPD). The right diaphragmatic lobe of the lung of 8 clinically healthy (unaffected) and 8 SPAOPD-affected horses was collected immediately after euthanasia. Bronchial rings (4 mm wide) were prepared and mounted in organ baths and attached to force transducers interfaced with a polygraph. Four rings were used to study each ET-1 receptor; 1 ring served as the control, and the other 3 were incubate...
Wales AD, Whitwell KE.Two samples were taken postmortem from the rectum of each of 14 horses with grass sickness and 10 control horses, and four sections stained with haematoxylin and eosin were examined. By using as a criterion of grass sickness the presence of three chromatolytic neurons, 10 of the 14 cases were positive and none of the control horses was positive, giving a sensitivity of 71 per cent and a specificity of 100 per cent. No other histological features appeared to be of diagnostic value, and staining for Nissl substance in neurons with cresyl fast violet and methyl green-pyronin did not improve the s...
Rütten M, Lehner A, Pospischil A, Sydler T.Listeria monocytogenes infection, although rare in horses, can lead to septicaemia, gastroenteritis and abortion or stillborn foals. Equine cerebral listeriosis has been reported, but only in newborn animals. This report describes a Freiberger gelding with severe neuronal symptoms of sudden onset. The animal collapsed within 24 h and was humanely killed. Necropsy revealed multiple small brown to reddish foci within the brain stem and pons. Histopathology demonstrated multifocal suppurative meningoencephalitis with microabscesses and occasional intra-lesional, coccoid to rod-shaped, bacteria. T...
Scott P, Witonsky S, Robertson J, Daft B.Equine protozoal myeloencephalitis (EPM), caused by Sarcocystis neurona infection in the central nervous system (CNS), affects up to 1% of all horses during their lifetimes. Neither the protective immune response nor the immunopathology associated with the disease is well understood. To begin to clarify the pathogenesis of the disease, immunohistochemical staining for B and T lymphocytes was performed on spinal cord sections obtained from 17 horses, all of which were all positive for S. neurona based on immunohistochemical staining. Fifteen of the 17 horses included in the study were killed du...
Singh K, Holbrook TC, Gilliam LL, Cruz RJ, Duffy J, Confer AW.Multisystemic eosinophilic epitheliotropic disease was diagnosed histologically in a 17-year-old Quarter Horse intact mare that was presented with a chronic history of respiratory distress. At necropsy, the lungs were poorly collapsed and the pulmonary parenchyma contained innumerable, discrete, spherical nodules in a miliary pattern. A few similar nodules were scattered in the liver and the renal lymph nodes. Histologically, these nodules consisted of fibrosing eosinophilic granulomas. Based on histologic findings and the absence of an etiologic agent, a diagnosis of multisystemic eosinophili...
Fjordbakk CT, Kenney DG, Rodriguez-Palacios A, Keller S, Stalker M.An inflammatory aural polyp was identified in a 1-year-old standardbred filly, which presented with otorrhea and head rubbing. The polyp was removed by traction-avulsion, and the filly showed no subsequent signs of otorrhea. Aural polyps have not been reported in horses, but they are commonly seen in companion animals and humans. Un polype auditif inflammatoire a été identifié chez une pouliche Standardbred d’un an présentée pour otorrhée et frottage de tête. Le polype a été retiré par traction-avulsion et la pouliche n’a pas manifesté de signes subséquents d’otorrhée. Les ...
Raftery AG, Jallow S, Coultous RM, Rodgers J, Sutton DGM.Equine trypanosomiasis is a severe and prevalent disease that has the greatest impact globally upon working equids due to its distribution across lower income countries. Morbidity and mortality rates are high; disease management strategies in endemic regions are ineffective and cost prohibitive. Individual variation in disease phenotype in other species suggests host factors could reveal novel treatment and control targets but has not been investigated in equids. Methods: A prospective clinical evaluation of equines presenting for a free veterinary examination was performed in hyperendemic vil...
Manohar M.Strenuously exercising Thoroughbreds exhibit a dramatic increase in pulmonary capillary blood pressure, which contributes to stress failure of pulmonary capillaries resulting in exercise induced pulmonary haemorrhage (EIPH). One strategy to prevent EIPH is, therefore, to lower the pulmonary capillary blood pressure of exercising horses. Recent work in several species suggests that nitric oxide plays a significant role in maintaining low vascular resistance in the pulmonary circulation; however, the effects of nitrovasodilators (which work via the same mechanism as nitric oxide) on equine pulmo...
Beaudry F, Vachon P.Glucosamine is an amino sugar involved in the biosynthesis of glycosylated proteins and lipids. Recently, with increased public interest in natural products medicine, glucosamine has been widely used to treat osteoarthritis, even though demonstrations of its actual efficacy remain relatively unknown. Information related to the pharmcokinetics of glucosamine is sparse. A recent analytical method published used 13C-glucosamine as an internal standard to analyse study samples. The method lacked accuracy owing to an important natural isotopic contribution of glucosamine to 13C-glucosamine ion abun...
van der Velden MA, Klein WR.Seventy horses surgically treated for colic caused by disorders of the small intestine were included in a randomized blind trial to determine the effects of cisapride (0.1 mg/kg bw intramuscularly at 8-h intervals) on the post-operative restoration of gut motility. Cisapride appeared to reduce the incidence of post-operative ileus. It accelerated the restoration of bowel motility, reducing the period of post-operative intensive care. It is concluded that cisapride is an effective and useful drug in the post-operative treatment of horses after surgery of the small intestine.
The Journal of nutritionDecember 30, 1998
Volume 128, Issue 12 Suppl 2698S-2703S doi: 10.1093/jn/128.12.2698S
Harris PA.In the first part of this century, there was little advancement in horse nutrition and little research was undertaken. However, in the last few years, there has been a great increase in interest in this whole area. This review surveys some of the more recent developments and how they have influenced feeding practices and also compares these with those feeding practices found at the start of this century. The review concentrates on the nutrition of the adult horse in work, exploring in particular what they are fed and how the nutrient value of these feeds is evaluated.
Nelson DM, Gardner IA, Chiles RF, Balasuriya UB, Eldridge BF, Scott TW, Reisen WK, Maclachlan NJ.Jamestown Canyon (JC) and Saint Louis encephalitis (SLE) viruses are mosquito-transmitted viruses that have long been present in California. The objective of this study was to determine the seroprevalence of these two viruses in horses prior to the introduction of West Nile (WN) virus. Approximately 15% of serum samples collected in 1998 from 425 horses on 44 equine operations horses throughout California had serum antibodies to JC virus, whereas antibodies were not detected to SLE virus. The results indicate that horses in California were commonly infected prior to 1998 with mosquito-transmit...
Sullivan SN, Cole SL, Stewart MC, Brokken MT, Durgam S.To investigate the effects of triamcinolone acetonide (TA) and methylprednisolone acetate (MPA) on the viability of resident cells within the fibrocartilage on the dorsal surface of the deep digital flexor tendon (FC-DDFT) and fibrocartilage on the flexor surface of the navicular bone (FC-NB) of horses. Methods: 12 to 14 explants of FC-DDFT and of FC-NB from grossly normal forelimbs of 5 cadavers of horses aged 9 to 15 years without evidence of musculoskeletal disease. Methods: Explants were incubated with culture medium (control) or TA-supplemented (0.6 or 6 mg/mL) or MPA-supplemented (0.5 or...
Robertson SA, Sanchez LC.Identification and alleviation of visceral pain is a frequent concern for the equine owner and veterinarian. This article discusses sources, methods for identification and quantitation, and options for treatment of visceral pain in horses.
Leach DH, Oliphant LW.The ultrastructure of cells of the secondary epidermal lamellae from the hoof wall of 8 adult horses was described. Stages of progressive keratinization were not observed in this cell population. The morphologic features of cells of the secondary epidermal lamellae indicated that these lamellae were composed of nonmobile populations of cells and that primary epidermal lamellae moved past the secondary lamellae by breaking of the desmosomes connecting these 2 cell populations. Seemingly, debris present in the intercellular space between primary and secondary lamellae was a by-product of this re...
Ipiña Z, Lussier JG, Theoret CL.To clone full-length equine pigment epithelium-derived factor (PEDF) complementary DNA (cDNA) and to evaluate its temporal expression during repair of wounds in horses. Methods: 4 clinically normal 2-to 3-year-old Standardbred mares. Methods: Full-length equine PEDF cDNA was cloned by screening size-selected cDNA libraries derived from biopsy specimens obtained from the wound edge 7 days after experimental creation of a 6.25-cm(2) full-thickness wound in the skin of the lateral thoracic wall. Expression was evaluated in normal skin and in biopsy specimens obtained weekly from experimentally in...
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...
Ginther OJ, Griffin PG.The natural outcome of bilateral twins (one in each uterine horn) that were viable on Day 40 was studied in 15 pony mares. Fetuses were monitored by transrectal ultrasonography until the outcome was determinable. One fetus (2 mares) or both fetuses (8 mares) died (cessation of heartbeats) during Months 2 and 3. Loss of fetuses was externally observed in 4 additional mares during the late fetal stage (Months 8 to 11); 2 mares lost 1 fetus and 2 lost both fetuses. Birth of 2 live foals occurred in only 1 of 15 mares (7%) First day of detected apposition between portions of the 2 allantochorions ...