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.
Fortier LA.Systemic therapies for joint disease may be prescribed when a single joint is involved or when multiple sites are affected. The precise therapeutic regimen recommended depends on the duration,cause, and site(s) of injury and is often an adjunct to intra-articular or supportive therapies. If the clinical signs of joint disease are acute and moderate in severity, nonsteroidal anti-inflammatory drugs are often administered to alleviate pain and inflammation. When aiming for more of a generalized maintenance or chondro-protective regimen, an alternative medication, such as hyaluronan,polysulfated ...
Marntell S, Nyman G, Hedenstierna G.To compare pulmonary function and gas exchange in anaesthetized horses during and after breathing either O2-rich gas mixtures or air. Methods: Six healthy standard bred trotters (age range 3-12 years; mass range 423-520 kg), four geldings and two mares. Study design Randomized, cross-over experimental study. Methods: Horses were anaesthetized on two occasions with tiletamine-zolazepam after pre-anaesthetic medication with acepromazine, romifidine and butorphanol. After endotracheal intubation and positioning in left lateral recumbency, animals were allowed to breathe spontaneously. One of two,...
Musilova P, Kubickova S, Vychodilova-Krenkova L, Kralik P, Matiasovic J, Hubertova D, Rubes J, Horin P.Chromosomal locations of 19 horse immunity-related loci (CASP1, CD14, EIF5A, FCER1A, IFNG, IL12A, IL12B, IL12RB2, IL1A, IL23A, IL4, IL6, MMP7, MS4A2, MYD88, NOS2A, PTGS2, TFRC and TLR2) were determined by fluorescence in situ hybridization. For IFNG and PTGS2, this study is a confirmation of their previously reported position. In addition, microsatellite (HMBr1) was localized in the same region as IFNG. All genes were assigned to regions of conserved synteny and the data obtained in this study enhance the comparative human-horse map. Cytogenetic localization of IL6 to ECA4q14-q21.1 suggested a...
Adami M, Faria MM, Almeida AE, Pinto MG, Prada IL.The present study examined the ultrastructure of the choroid plexus of the lateral ventricle of the horse. The material was fixed in 2.5% glutaraldehyde in 0.1 m sodium phosphate buffer, pH 7.3, processed and analysed by scanning electron microscopy. The choroid plexus was characterized by regions with a predominance of villi, which resembled finger-like projections or bunches of grapes, and others where straight and uniform folds predominated. Epithelial cells projected into the ventricle and large amounts of cilia and microvilli were observed on their surface. The choroid glomus corresponded...
Milenkovic D, Mata X, Chadi S, Guérin G.Laminins are large heterotrimeric basement membrane glycoproteins composed of alpha, beta and gamma chains. The Laminin 5 isoform has an alpha3beta3gamma2 composition and is essential for the adhesion of basal keratinocytes to the underlying epithelial basement membrane where it is mainly located. Mutations in the genes coding for the 3 chains have been associated with a severe skin blistering disease, Herlitz's junctional epidermolysis bullosa (JEB), observed in different species as man, dog, cat and horse. In this study, we report the sequence of the 5.2 kb horse laminin alpha 3 cDNA (LAMA3)...
Mittelholzer C, Johansson I, Olsson AK, Ronéus M, Klingeborn B, Belák S.Recovery of infectious Equine arteritis virus (EAV) from the semen of persistently infected Swedish stallions was attempted by classical cell culture isolation and by transfection of extracted total RNA. Whereas virus from semen samples stored for several months at -20 degrees C or from extended semen could only be recovered by transfection of extracted RNA, isolation in cell culture was achieved readily with fresh, unextended semen stored at -70 degrees C or directly used after sampling. In parallel, the viruses were examined in the variable region of the large glycoprotein GP5 by nested RT-P...
McGurrin MK, Physick-Sheard PW, Kenney DG.Electrical cardioversion of atrial fibrillation is a well-established technique for restoration of sinus rhythm in humans. While transthoracic cardioversion is more commonly used, transvenous electrical cardioversion (TVEC) has been reported as having higher efficacy at substantially lower energy levels. In horses, treatment of atrial fibrillation has essentially been limited to the administration of quinidine salts either orally or intravenously. TVEC provides an alternative to quinidine salts, especially for those animals in which quinidine is neither effective nor tolerated. The present rep...
Brindley MA, Maury W.Recently, it has become evident that entry of some retroviruses into host cells is dependent upon a vesicle-localized, low-pH step. The entry mechanism of equine infectious anemia virus (EIAV) has yet to be examined. Here, we demonstrate that wild-type strains of EIAV require a low-pH step for productive entry. Lysosomotropic agents that inhibit the acidification of internal vesicles inhibited productive entry of EIAV. The presence of ammonium chloride (30 mM), monensin (30 microM), or bafilomycin A (50 nM) in the medium dramatically decreased the number of EIAV antigen-positive cells. We foun...
Hurley DJ, Parks RJ, Reber AJ, Donovan DC, Okinaga T, Vandenplas ML, Peroni JF, Moore JN.Administration of black walnut heartwood extract (BWHE) via nasogastric tube induces acute laminitis in horses. However, the processes responsible for the development of laminitis, including laminitis induced with BWHE, remain unclear. The results of recent studies indicate that administration of BWHE initiates an inflammatory response in the laminar tissues and that this response may be due to extravasation of activated leukocytes from the circulation. This study examines the effects of BWHE administration on the dynamics of circulating neutrophils and monocytes, and the capacity of blood leu...
Murray JA, Longland AC, Moore-Colyer MJ, Dunnett C.A series of experiments was conducted to determine the effects of a fibrolytic enzyme preparation (enzyme 1; E1) on the in vitro fermentation of lucerne incubated with equine faecal inocula. In experiment 1, high-temperature-dried (HT) lucerne was treated with five levels of E1 (0 to 2.4 ml/g DM) and incubated at 50 degrees C for 20 h. Samples then received a simulated foregut digestion (SFD) treatment before DM and NSP analysis. In experiment 2, HT lucerne was treated with the same enzyme levels used in experiment 1. Samples were then split into two groups; plus or minus an SFD treatment befo...
Ishihara A, Bertone AL, Rajala-Schultz PJ.To evaluate the association between subjective lameness grades and kinetic gait parameters and assess the variability in kinetic parameters in horses with experimentally induced forelimb lameness. Methods: 32 horses. Methods: Forelimb lameness was induced in each horse via injection of lipopolysaccharide into 1 metacarpophalangeal joint (40 experimental trials). Subjective lameness grading and 13 kinetic gait parameters (force plate analysis) were assessed before (baseline) and at 12, 18, and 24 hours after lipopolysaccharide injection. While horses were trotting, kinetic gait analysis was per...
Byron CR, Benson BM, Stewart AA, Stewart MC.To investigate in vitro effects of radial shock waves on membrane permeability, viability, and structure of chondrocytes and articular cartilage. Methods: Cartilage explants obtained from the third metacarpal and metatarsal bones of 6 horses. Methods: Equine cartilage was subjected to radial shock waves and then maintained as explants in culture for 48 hours. Treatment groups consisted of a negative control group; application of 500, 2,000, and 4,000 impulses by use of a convex handpiece (group A); and application of 500, 2,000, and 4,000 impulses by use of a concave handpiece (group B). Effec...
Anielski P, Thieme D, Schlupp A, Grosse J, Ellendorff F, Mueller RK.Growing interest among several horse-breeder associations has initiated the development of a screening procedure to test for anabolic agents in hair, which has the advantage over blood and urine specimens of allowing long-term detection. An analytical method was established to monitor in tails or manes several anabolic substances available as veterinary medicines or as so-called nutritional supplements (clenbuterol, different esters or prohormones of nandrolone and testosterone). The analytical procedure to detect steroids in hair samples consists of the following steps: decontamination of the...
Craig MI, Barrandeguy ME, Fernández FM.Equine herpesvirus 2 is a gamma-herpesvirus that infects horses worldwide. Although EHV-2 has been implicated in immunosuppression in foals, upper respiratory tract disease, conjunctivitis, general malaise and poor performance, its precise role as a pathogen remains uncertain. The purpose of the present study was to analyse the incidence of EHV-2 in an Argentinean horse population and correlate it with age and clinical status of the animals. Results: A serological study on 153 thoroughbred racing horses confirmed the presence of EHV-2 in the Argentinean equine population. A virus neutralizatio...
Lewis CW, Williamson AK, Chen AC, Bae WC, Temple MM, Wong WV, Nugent GE, James SP, Wheeler DL, Sah RL, Kawcak CE.To determine and correlate subchondral bone mineral density and overlying cartilage structure and tensile integrity in mature healthy equine stifle (low magnitude loading) and metacarpophalangeal (high magnitude loading) joints. Methods: 8 healthy horses, 2 to 3 years of age. Methods: Osteochondral samples were acquired from the medial femoral condyle (FC) and medial trochlear ridge (TR) of the stifle joint and from the dorsal (MC3D) and palmar (MC3P) aspects of the distal medial third metacarpal condyles of the metacarpophalangeal joint. Articular cartilage surface fibrillation (evaluated via...
Rankin SC, Whichard JM, Joyce K, Stephens L, O'shea K, Aceto H, Munro DS, Benson CE.Salmonella enterica serovar Newport MDR-AmpC expressing TEM-1b and extended-spectrum beta-lactamase SHV-12 was isolated from affected animals during an outbreak of salmonellosis that led to a 3-month closure of one of the largest equine hospitals in the United States.
Tallmadge RL, Lear TL, Antczak DF.The availability of a contig of bacterial artificial chromosome (BAC) clones spanning the equine major histocompatibility complex (MHC) made possible a detailed analysis of horse MHC class I genes. Prior to this study, only a single horse MHC class I gene had been sequenced at the genomic level. Although many ( approximately 60) MHC class I cDNA sequences had been determined and published, from this information, it was not possible to determine how many class I loci are expressed in horses or to assign individual sequences to allelic series. In this study, 15 MHC class I genes were identified ...
Peham C, Schobesberger H.Diagnosis of back problems in equine orthopedics can be a difficult task. The aim of our study was to develop a new method for estimating the stiffness of the equine back in vivo. We measured the activity of the long back muscle at two locations on both sides at thoracic vertebrae T12 and T16 of 15 horses flexing and extending their back at stance using telemetric surface electromyography, while simultaneously recording the motion of the back with a video camera system. Out of these paired data sets we computed a transfer function in the frequency domain and evaluated its capability of capturi...
Hemberg E, Lundeheim N, Einarsson S.Changes in the conformation of the vulva predispose the mare to uterine infection. Vulvoplasty for closure of the upper vulvar lips improves fertility. Not all mares are resutured after parturition, but are resutured after mating. No clinical data have hitherto been published on the reproductive outcome in mares that are resutured or not after parturition. The objectives of the present study were to investigate relationships between vulvar status (not Caslick-operated, group A; previously Caslick-operated and/or not resutured after the last parturition, groups B and C respectively) and endomet...
Doube M, Firth EC, Boyde A.Combined backscattered electron scanning electron microscopy (BSE SEM) and confocal scanning laser microscopy (CSLM) have been used to put tissue mineralization data into the context of soft tissue histology and fluorescent label information. Mineralization density (Dm) and linear accretion rate (LAR) are quantifiable parameters associated with mineralizing fronts within calcified tissues. Quantitative BSE (qBSE) may be used to determine Dm, while CSLM may be used to detect label fluorescence from which LAR is calculated. Eighteen-month old Thoroughbred horses received single calcein injection...
Muir P, McCarthy J, Radtke CL, Markel MD, Santschi EM, Scollay MC, Kalscheur VL.The mechanisms that regulate functional adaptation of the articular ends of long bones are poorly understood. However, endochondral ossification of articular cartilage and modeling/remodeling of the subchondral plate and epiphyseal trabeculae are important components of the adaptive response. We performed a histologic study of the distal end of the third metacarpal/metatarsal bone of Thoroughbreds after bones were bulk-stained in basic fuchsin and calcified sections were prepared. The Thoroughbred racehorse is a model of an extreme athlete which experiences particularly high cyclic strains in ...
Harlow BE, Lawrence LM, Harris PA, Aiken GE, Flythe MD.Cereal grains are often included in equine diets. When starch intake exceeds foregut digestion starch will reach the hindgut, impacting microbial ecology. Probiotics (e.g., lactobacilli) are reported to mitigate GI dysbioses in other species. This study was conducted to determine the effect of exogenous lactobacilli on pH and the growth of amylolytic and lactate-utilizing bacteria. Feces were collected from 3 mature geldings fed grass hay with access to pasture. Fecal microbes were harvested by differential centrifugation, washed, and re-suspended in anaerobic media containing ground corn, whe...
Monteiro RA, Cunha RM, Guerra MMP, de Almeida VM, Peña-Alfaro CE, Silva SV.The aim of this study was to test equine semen cryopreservation techniques for the conservation of donkey germplasm. Ejaculates of three male donkeys were used (n = 18; six ejaculates per donkey; six repetitions), collected by the artificial vagina method. To remove the seminal plasma, the ejaculates were split and submitted to filtration or centrifugation methods. To assess the freezing method, each fraction was submitted to the automated system or the conventional system, and groups were formed: automated centrifuge, automated filtrate, conventional centrifuge and conventional filtrate. Af...
Norman WM, Williams R, Dodman NH, Kraus AE.After surgery, high intramuscular pressures were measured in a horse with clinical signs of postanesthetic myopathy that developed following a 2.25-hour surgical procedure. In the postoperative period, tests for muscular and neurologic integrity were made, including measurement of intracompartmental muscle pressure.
Santos MP, Gutierrez-Nibeyro SD, Horn GP, Johnson AJ, Stewart MC, Schaeffer DJ.To compare the mechanical properties of laryngeal tie-forward (LTF) surrogate constructs prepared with steel fixtures and No. 5 braided polyester or braided polyethylene by use of a standard or a modified suture placement technique. Methods: 32 LTF surrogate constructs. Methods: Surrogate constructs were prepared with steel fixtures and sutures (polyester or polyethylene) by use of a standard or modified suture placement technique. Constructs underwent single-load-to-failure testing. Maximal load at failure, elongation at failure, stiffness, and suture breakage sites were compared among constr...
Stratton LG, Corstvet R, Brown J, Corley L.K. pneumoniae capsule type 68 infused into the uterus of 4 mares was recovered up to 15 weeks after inoculation. The insertion of a tampon for 10 min was more effective than a swab technique in detecting the organism in the uterus. The clitoral fossa and the urethral orifice when sampled by the swab technique were also found to be infected for a comparable period. K. pneumoniae was isolated from the clitoral specimens more often and more consistently than from either urethral or uterine specimens.
Morris ERA, Wu J, Bordin AI, Lawhon SD, Cohen ND.Streptococcus equi subsp. (SEE) is a host-restricted equine pathogen considered to have evolved from Streptococcus equi subsp. (SEZ). SEZ is promiscuous in host range and is commonly recovered from horses as a commensal. Comparison of a single strain each of SEE and SEZ using whole-genome sequencing, supplemented by PCR of selected genes in additional SEE and SEZ strains, was used to characterize the evolution of SEE. But the known genetic variability of SEZ warrants comparison of the whole genomes of multiple SEE and SEZ strains. To fill this knowledge gap, we utilized whole-genome sequenci...
Matthews AG, Crispin SM, Parker J.A wide range of fundic variants are encountered during routine ophthalmoscopic examination of visually normal horses, often causing the examiner difficulty in assessing their clinical significance. Many of these are anatomical variants having no significant effect on visual function, and lie within the limits of normality in the horse. This paper illustrates this range of variants and discusses their anatomical basis and physiological consequences. Colobomata are non-progressive discontinuities in the structure of the anatomic fundus, occasionally noted as incidental findings during ophthalmos...
Guasti PN, Monteiro GA, Maziero RR, Carmo MT, Dell'Aqua JA, Crespilho AM, Rifai EA, Papa FO.The aims of this study were to determinate whether pentoxifylline (PTX) increases the motion parameters of fresh and frozen-thawed equine epididymal spermatozoa, to evaluate the tyrosine phosphorylation of frozen-thawed epididymal sperm in the presence of PTX and to determine whether the PTX-treatment of stallion epididymal sperm prior to freezing improves the fertility response of mares to a reduced number of spermatozoa per insemination dose. Fifty epididymis were flushed with a skim milk based extender with or without PTX. The pre-treatment with PTX enhanced the sperm motility after being h...
Karagianni AE, Summers KM, Couroucé A, Depecker M, McGorum BC, Hume DA, Pirie RS.Mild-to-moderate equine asthma is prevalent in young racehorses, particularly early in their training period. Although the precise etiopathogenesis remains undetermined, it is possible that the susceptibility of this population might partly reflect an exercise-associated immune derangement at the level of the airway. We performed a genome-wide basal gene expression scan on alveolar macrophages (AMs) isolated from Standardbred racehorses before and after commencement of competition race training with a view to identifying any exercise-associated gene expression modulation consistent with functi...
Beachler TM, Gracz HS, Morgan DR, Bembenek Bailey SA, Borst L, Ellis KE, Von Dollen KA, Lyle SK, Nebel A, Andrews NC, Koipalli J, Gadsby JE, Bailey CS.Metabolomics may represent an avenue for diagnosis of equine ascending placentitis. Objective: To characterise the plasma metabolomic profile in healthy mares and mares with induced ascending placentitis, with the goal of identifying metabolites with potential clinical value for early diagnosis of placentitis. Methods: Controlled in vivo experiment. Methods: Placentitis was induced in 10 late-term pregnant pony mares via Streptococcal equi subsp. zooepidemicus inoculation in five mares between days 285 and 290 of gestation, while five mares served as healthy controls. Repeated ultrasound exami...
McGlothlin JA, Lester GD, Hansen PJ, Thomas M, Pablo L, Hawkins DL, LeBlanc MM.An experimental model of ascending placentitis was developed in the mare to characterize the uterine myoelectrical pattern in late gestation and determine how ascending placentitis altered this pattern. In experiment 1, myometrial electrical activity was analyzed during the early morning, late morning and evening hours in four mares in the last 15 days of gestation to identify patterns of activity. In experiment 2, nine mares received intra-cervical inoculations of Streptococcus equi subspecies zooepidemicus. Myoelectrical activity in the early morning and evening hours in these mares was comp...
Oesch S, Kaiser-Thom S, Vidondo B, Gerber V.Equine pastern dermatitis has a high prevalence in the equine population, especially in draft breeds. This skin condition is difficult to treat, and it is suspected that owners often decide on a treatment without consulting a veterinarian. The objectives of this study were to describe owner-reported clinical signs, severity, and reasons to consult a veterinarian. Moreover, we inquired about preventive measures and treatments, both instituted by owners without previous consultation or prescribed by their veterinarians. A total of 123 horses (owners recruited over social media) were included in ...
Schulze N, Ehrle A, Weller R, Fritsch G, Gernhardt J, Ben Romdhane R, Lischer C. Surgical fusion of vertebral segments is a treatment option for horses with cervical stenotic myelopathy or cervical fracture.Degenerative disease affecting adjacent vertebral segments is a reported complication following surgical vertebral fusion in other species, termed adjacent segment disease. The aim of this study was to evaluate the impact of cervical vertebral fusion on the biomechanics of adjacent vertebral segments in the horse. Methods: Neck specimens of 12 horses were assessed using computed tomographic imaging. Range of motion (ROM) was determined by measuring the maximum sag...
Wiedner EB, Lindsay WA, Isaza R.Equine practitioners are sometimes asked to treat zebras or zebra-horse or zebra-donkey hybrids. Although these equids are subject to many of the same health issues as domestic horses, they cannot be handled like horses and generally require heavy sedation to full anesthesia, even for minor procedures. This usually necessitates the use of ultrapotent narcotics administered by remote delivery systems. This article discusses the handling, sedation, anesthesia, and common medical issues of zebras and zebra hybrids.