Analyze Diet

Topic:Clinical Study

Clinical studies in equine research involve the systematic investigation of health and disease in horses through structured scientific methods. These studies aim to evaluate the safety and efficacy of treatments, understand disease mechanisms, and improve veterinary care practices. Clinical studies can include randomized controlled trials, observational studies, and case-control studies. They may focus on various aspects such as pharmacokinetics, therapeutic interventions, and diagnostic techniques. This page compiles peer-reviewed research studies and scholarly articles that explore the design, implementation, and findings of clinical studies in equine medicine, providing insights into their impact on horse health and veterinary practices.
A preliminary report on a fat-free diet formula for nasogastric enteral administration as treatment for hyperlipaemia in ponies.
The veterinary quarterly    January 5, 2002   Volume 23, Issue 4 201-205 doi: 10.1080/01652176.2001.9695114
Hallebeek JM, Beynen AC.A fat-free liquid diet was formulated to be administered by nasogastric tube as therapy for hyperlipaemia in ponies. The liquid diet provided energy, protein, minerals, trace elements, and vitamins in accordance with the requirements of ponies. As sole source of nutrition, the liquid diet fully counteracted fasting-induced hyperlipaemia in two healthy ponies. The liquid diet was also used in hyperlipaemic patients, but only in combination with conventional therapy, consisting of intravenous administration of glucose, insulin, and heparin. Although no patients were treated with the liquid diet ...
Factors influencing the occurrence of thrombophlebitis after post-surgical long-term intravenous catheterization of colic horses: a study of 38 cases.
Journal of veterinary medicine. A, Physiology, pathology, clinical medicine    January 5, 2002   Volume 48, Issue 9 545-552 doi: 10.1046/j.1439-0442.2001.00383.x
Lankveld DP, Ensink JM, van Dijk P, Klein WR.Thrombophlebitis is a well-known complication of the use of long-term in-dwelling catheters. In humans, catheter material has been shown to strongly influence the occurrence of thrombophlebitis. In the horse, the influence of catheter material has been studied in healthy experimental animals, but information on the relative importance of this factor is lacking. To investigate which factors have most impact on the frequency of jugular vein thrombosis in post-surgical colic horses, a clinical study was performed on 38 animals. Horses were randomly divided into two groups. In one group a polytetr...
Effects of topical administration of 0.005% latanoprost solution on eyes of clinically normal horses.
American journal of veterinary research    January 5, 2002   Volume 62, Issue 12 1945-1951 doi: 10.2460/ajvr.2001.62.1945
Willis AM, Diehl KA, Hoshaw-Woodard S, Kobayashi I, Vitucci MP, Schmall LM.To determine the effect of 0.005% latanoprost solution on intraocular pressure (IOP) of eyes of clinically normal horses and establish the frequency of adverse effects of drug administration. Methods: 20 adult clinically normal horses. Methods: IOP was recorded (7, 9, and 11 AM; 3, 5, and 7 PM) on days 1 and 2 (baseline), days 3 to 7 (treatment), and days 8 to 9 (follow-up). Latanoprost was administered to 1 randomly assigned eye of each horse every 24 hours during the treatment period, following the 7 AM IOP recording. Pupil size and the presence or absence of conjunctival hyperemia, epiphora...
IgG antibody responses to an inhaled antigen in horses with “heaves” (recurrent airway obstruction).
Veterinary immunology and immunopathology    January 5, 2002   Volume 84, Issue 3-4 169-180 doi: 10.1016/s0165-2427(01)00400-7
Ainsworth DM, Appleton JA, Antczak DF, Santiago MA, Aviza G.A controlled experimental system for the evaluation of pulmonary immune responses in horses with "heaves" (recurrent airway obstruction) has been developed. We hypothesized that the humoral immune response to an inhaled antigen in diseased horses would be different from that of healthy horses and that chronic pulmonary inflammation would bias the production of IgG isotypes in diseased horses as compared to healthy horses. Healthy and affected horses were housed in a natural challenge environment (stabled, fed dusty hay) and exposed by inhalation, to a nebulized solution of keyhole limpet hemoc...
Cardiopulmonary function in horses during anesthetic recovery in a hydropool.
American journal of veterinary research    January 5, 2002   Volume 62, Issue 12 1903-1910 doi: 10.2460/ajvr.2001.62.1903
Richter MC, Bayly WM, Keegan RD, Schneider RK, Weil AB, Ragle CA.To determine the cardiovascular and respiratory effects of water immersion in horses recovering from general anesthesia. Methods: 6 healthy adult horses. Methods: Horses were anesthetized 3 times with halothane and recovered from anesthesia while positioned in lateral or sternal recumbency in a padded recovery stall or while immersed in a hydropool. Cardiovascular and pulmonary functions were monitored before and during anesthesia and during recovery until horses were standing. Measurements and calculated variables included carotid and pulmonary arterial blood pressures (ABP and PAP respective...
Comparison of the clearance of 99mTechnetium-DTPA from the lung and lung function indices derived from the single breath diagram for carbon dioxide in horses with chronic obstructive pulmonary disease.
Journal of veterinary medicine. A, Physiology, pathology, clinical medicine    January 5, 2002   Volume 48, Issue 9 553-561 doi: 10.1046/j.1439-0442.2001.00384.x
Herholz C, Phillip M, Straub R, Ueltschi G, Busato A.The elimination of carbon dioxide from the lung can be used to monitor ventilation and perfusion, and 99mtechnetium-diethylenetriaminepentaacetate (99mTc-DTPA) clearance is a highly sensitive index of alveolar epithelial integrity, which is a presupposition for effective gas exchange. The aim of this study was to determine whether a correlation exists between indices of lung function derived from the single breath diagram for CO2, and 99mTc-DTPA clearance in horses with chronic obstructive pulmonary disease. The rate of 99mTc-DTPA elimination was negatively and substantially correlated with th...
Use of an intravitreal sustained-release cyclosporine delivery device for treatment of equine recurrent uveitis.
American journal of veterinary research    January 5, 2002   Volume 62, Issue 12 1892-1896 doi: 10.2460/ajvr.2001.62.1892
Gilger BC, Wilkie DA, Davidson MG, Allen JB.To evaluate the use of an intravitreal sustained-release cyclosporine (CsA) delivery device for treatment of horses with naturally occurring recurrent uveitis. Methods: 16 horses with recurrent uveitis. Methods: Horses with frequent recurrent episodes of uveitis or with disease that was progressing despite appropriate medication were selected for this study. Additional inclusion criteria included adequate retinal function as determined by use of electroretinography, lack of severe cataract formation, and no vision-threatening ocular complications (eg, retinal detachment, severe retinal degener...
Duration of immunity induced by an adjuvanted and inactivated equine influenza, tetanus and equine herpesvirus 1 and 4 combination vaccine.
The veterinary quarterly    January 5, 2002   Volume 23, Issue 4 210-217 doi: 10.1080/01652176.2001.9695116
Heldens JG, Kersten AJ, Weststrate MW, van den Hoven R.An adjuvanted vaccine containing inactivated equine influenza, herpesvirus antigens, and tetanus toxoid was administered to young seronegative foals of 8 months of age by deep intramuscular injection in the neck (Group A). The first two vaccinations were given 4 weeks apart. The third was administered 6 months later. Another group of foals (Group B) was vaccinated according to the same scheme at the same time with monovalent equine herpes virus (EHV) vaccine (EHV1.4) vaccine. Antibody responses to the equine influenza (single radial haemolysis; SRH) and tetanus (ToBi ELISA) components of the v...
Effects of ‘navicular’ shoeing on equine distal forelimb kinematics on different track surface.
The veterinary quarterly    January 5, 2002   Volume 23, Issue 4 191-195 doi: 10.1080/01652176.2001.9695111
Scheffer CJ, Back W.Orthopaedic shoeing applied for disorders such as navicular disease is mostly evaluated on hard track surfaces, but very often horses are ridden only on soft tracks. To compare the effects of normal shoes, eggbar shoes, and shoes with heel wedges (5 degrees) on the kinematics of the distal forelimb on hard and soft track surfaces, eleven sound Dutch Warmblood horses were led across three different tracks (an asphalt, a fibre/sand mix (= Agterberg), and a pure sand track) with three different shoe types (a normal shoe, an eggbar shoe, and a shoe with heel wedges). The hoof rotation and the maxi...
Immunoglobulin-E-bearing cells in skin biopsies of horses with insect bite hypersensitivity.
Equine veterinary journal    January 5, 2002   Volume 33, Issue 7 699-706 doi: 10.2746/042516401776249444
van der Haegen A, Griot-Wenk M, Welle M, Busato A, von Tscharner C, Zurbriggen A, Marti E.The aim of the present study was to investigate, with immunohistochemistry and in situ hybridisation, if immunoglobulin-E (IgE) and mast cells are involved in the pathogenesis of insect bite hypersensitivity (IBH), an allergic dermatitis of horses. In tissue sections fixed in paraformaldehyde (PFA) for <24 h, significantly more IgE protein-bearing cells were found in the dermis and epidermis of acute and chronic IBH lesions than in skin biopsies from healthy horses (medians = 466, 236 and 110 cells/mm2, respectively; P < or = 0.01). More IgE-mRNA positive (+) cells were observed in the dermis ...
Ultrasonography of the podotrochlear apparatus in the horse using a transcuneal approach: technique and reference images. Busoni V, Denoix JM.The purpose of this paper is to describe the technique for ultrasonographic examination of the podotrochlear apparatus in the horse using a transcuneal approach. In this study, ultrasound scans were performed in 3 normal cadaver limbs and 5 sound horses and images were compared to anatomic sections to establish the normal ultrasonographic anatomy of the podotrochlear apparatus. Detailed description of transverse and sagittal reference ultrasonographic images of this region is provided. This new imaging technique allows the assessment of the distal sesamoid bone flexor surface, the distal porti...
Efficacy of a cold-adapted, intranasal, equine influenza vaccine: challenge trials.
Equine veterinary journal    January 5, 2002   Volume 33, Issue 7 637-643 doi: 10.2746/042516401776249354
Townsend HG, Penner SJ, Watts TC, Cook A, Bogdan J, Haines DM, Griffin S, Chambers T, Holland RE, Whitaker-Dowling P, Youngner JS, Sebring RW.A randomised, controlled, double-blind, influenza virus, aerosol challenge of horses was undertaken to determine the efficacy of a cold-adapted, temperature sensitive, modified-live virus, intranasal, equine influenza vaccine. Ninety 11-month-old influenza-naïve foals were assigned randomly to 3 groups (20 vaccinates and 10 controls per group) and challenged 5 weeks, 6 and 12 months after a single vaccination. Challenges were performed on Day 0 in a plastic-lined chamber. Between Days 1 and 10, animals were examined daily for evidence of clinical signs of influenza. Nasal swabs for virus isol...
Effects of oral administration of phenylbutazone to horses on in vitro articular cartilage metabolism.
American journal of veterinary research    January 5, 2002   Volume 62, Issue 12 1916-1921 doi: 10.2460/ajvr.2001.62.1916
Beluche LA, Bertone AL, Anderson DE, Rohde C.To evaluate the effects of orally administered phenylbutazone on proteoglycan synthesis and chondrocyte inhibition by IL-1beta in articular cartilage explants of horses. Methods: 11 healthy 1- to 2-year-old horses. Methods: Horses were randomly assigned to the control (n = 5) or treated group (4.4 mg of phenylbutazone/kg of body weight, p.o., q 12 h; n = 6). Articular cartilage specimens were collected before treatment was initiated (day 0), after 14 days of treatment, and 2 weeks after cessation of treatment (day 30). Proteoglycan synthesis and stromelysin concentration in cartilage extracts ...
Detection of IgG and IgE serum antibodies to Culicoides salivary gland antigens in horses with insect dermal hypersensitivity (sweet itch).
Equine veterinary journal    January 5, 2002   Volume 33, Issue 7 707-713 doi: 10.2746/042516401776249363
Wilson AD, Harwood LJ, Björnsdottir S, Marti E, Day MJ.We postulated that all horses exposed to the bites of Culcoides (midges) would have an antibody response to the antigen secreted in Culcoides saliva, but that IgE antibody would be restricted to allergic individuals. Using immunohistology on sections of fixed Culicoides, we have demonstrated the presence of antibodies in horse serum which recognise Culicoides salivary glands. Antibodies were detected in the serum of horses with insect dermal hypersensitivity and in the serum of normal horses exposed to Culicoides bites. In contrast, no antibodies were detected in serum from native Icelandic po...
Evaluation of IgG concentration and IgG subisotypes in foals with complete or partial failure of passive transfer after administration of intravenous serum or plasma.
Equine veterinary journal    January 5, 2002   Volume 33, Issue 7 681-686 doi: 10.2746/042516401776249273
McClure JT, DeLuca JL, Lunn DP, Miller J.The purpose of this study was to evaluate the ability of an equine plasma product i.v. and a concentrated serum product i.v. to deliver antibodies to 46 foals with failure of passive transfer (FPT). Treatment of FPT was as per manufacturers recommendations, using plasma (950 ml/unit) or a concentrated serum product (250 ml/unit). Significant variables affecting the 3 day post-transfusion serum immunoglobulin G (IgG) concentration of foals included body weight, pretransfusion IgG concentration, number of product units transfused, foaling season and product administered. Plasma treatment had a g...
A new modified live equine influenza virus vaccine: phenotypic stability, restricted spread and efficacy against heterologous virus challenge.
Equine veterinary journal    January 5, 2002   Volume 33, Issue 7 630-636 doi: 10.2746/042516401776249291
Chambers TM, Holland RE, Tudor LR, Townsend HG, Cook A, Bogdan J, Lunn DP, Hussey S, Whitaker-Dowling P, Youngner JS, Sebring RW, Penner SJ....Flu Avert IN vaccine is a new, live attenuated virus vaccine for equine influenza. We tested this vaccine in vivo to ascertain 1) its safety and stability when subjected to serial horse to horse passage, 2) whether it spread spontaneously from horse to horse and 3) its ability to protect against heterologous equine influenza challenge viruses of epidemiological relevance. For the stability study, the vaccine was administered to 5 ponies. Nasal swabs were collected and pooled fluids administered directly to 4 successive groups of naïve ponies by intranasal inoculation. Viruses isolated from th...
Arthrodesis of the equine proximal interphalangeal joint: a biomechanical comparison of two 7-hole 3.5-mm broad and two 5-hole 4.5-mm narrow dynamic compression plates.
Veterinary surgery : VS    January 5, 2002   Volume 31, Issue 1 85-93 doi: 10.1053/jvet.2002.29457
Watt BC, Edwards RB, Markel MD, McCabe R, Wilson DG.To compare the biomechanical characteristics and mode of failure of two different dynamic compression plate (DCP) techniques for proximal interphalangeal joint (PIPJ) arthrodesis in horses. Methods: Randomized block-design blocking on horse (1-5), method of fixation (two 7-hole, 3.5-mm broad DCP vs two 5-hole, 4.5-mm narrow DCP), side (left, right), and end (front, hind). Constructs were loaded to failure in 3-point bending in a dorsal-to-palmar (plantar) direction. Methods: Ten paired limbs from 5 equine cadavers. Methods: Two 7-hole, 3.5-mm broad dynamic compression plates (bDCP) were used i...
The equine larynx.
New Zealand veterinary journal    January 1, 2002   Volume 50, Issue sup3 117 doi: 10.1080/00480169.2002.36286
Goulden B.Abstract Extract A series of landmark studies on the function of the equine larynx was conducted by a group of researchers at Massey University between 1970 and 1987. These studies commenced with investigations on the normal laryngeal anatomy and physiology (Goulden et al 1976a; Anderson et al 1980; Quinlan et al 1982), and progressed to a clinical appraisal of laryngeal hemiplegia, the most important clinical disease affecting the horse's larynx (Goulden and Anderson 198 lab, 1982). The studies concluded with a series of in-depth cytological and pathological studies of the intrinsic laryngeal...
Blood plasma concentrations of insulin-like growth factor-I (IGF-I) in resting standardbred horses.
Veterinary journal (London, England : 1997)    December 26, 2001   Volume 163, Issue 1 45-50 doi: 10.1053/tvjl.2001.0619
Champion ZJ, Breier BH, Ewen WE, Tobin TT, Casey PJ.A survey of standardbred horses was conducted to build up a normal population profile for insulin like growth factor-I (IGF-I) concentrations in racing standardbreds and to ascertain how age, sex and geographic location affect IGF-I. Blood samples were drawn by jugular venepuncture from 202 racing standardbred horses aged one to eight years located in five different geographic regions of New Zealand. IGF-I concentrations were determined by insulin like growth factor-I binding protein (IGFBP)-blocked radioimmunoassay validated for the horse. As described in other species, age played a significa...
World association for the advancement of veterinary parasitology (WAAVP): second edition of guidelines for evaluating the efficacy of equine anthelmintics.
Veterinary parasitology    December 26, 2001   Volume 103, Issue 1-2 1-18 doi: 10.1016/s0304-4017(01)00574-x
Duncan JL, Abbott EM, Arundel JH, Eysker M, Klei TR, Krecek RC, Lyons ET, Reinemeyer C, Slocombe JO.These guidelines have been designed to assist in the planning, operation and interpretation of studies which would serve to assess the efficacy of drugs against internal parasites of horses. Although the term anthelmintic is used in the title and text, these guidelines include studies on drug efficacy against larvae of horse bot flies, Gasterophilus spp., which are non-helminth parasites commonly occurring in the stomach of horses. The advantages, disadvantages and application of critical and controlled tests are presented. Information is also provided on selection of animals, housing, feed, d...
Computerized detection of supporting forelimb lameness in the horse using an artificial neural network.
Veterinary journal (London, England : 1997)    December 26, 2001   Volume 163, Issue 1 77-84 doi: 10.1053/tvjl.2001.0608
Schobesberger H, Peham C.The purpose of this study was to investigate whether artificial neural networks could be used to determine equine lameness by computational means only. The integral parts of our approach were the combination of automated signal tracking of horses on a treadmill and the computational power of artificial neural networks (ANN). The motion of 175 horses trotting on a treadmill was recorded using the SELSPOT II system for motion analysis. Two cameras traced infrared (IR) markers on the head and on the left forehoof. The motion of the head was Fourier-transformed and further processed by a multilaye...
Advances in cryopreservation of stallion semen in modified INRA82.
Animal reproduction science    December 18, 2001   Volume 68, Issue 3-4 201-218 doi: 10.1016/s0378-4320(01)00157-9
Vidament M, Yvon JM, Couty I, Arnaud G, Nguekam-Feugang J, Noue P, Cottron S, Le Tellier A, Noel F, Palmer E, Magistrini M.In the procedure used in this paper, semen was first diluted in INRA82+2% egg yolk (E1) at 37 degrees C. Before or after cooling to 4 degrees C, semen was centrifuged and diluted in E1+2.5% glycerol (E2). Cooled semen was frozen in 0.5-ml straws. Straws were thawed at 37 degrees C for 30s. For fertility trials, frozen ejaculates were used only if total post-thaw motility was above 35%. Most mares were inseminated two times before ovulation with 400 x 10(6) total spermatozoa every 24h. This paper presents post-thaw motility (CASA) and fertility results obtained when some steps of the procedure ...
Advances in cooled semen technology.
Animal reproduction science    December 18, 2001   Volume 68, Issue 3-4 181-190 doi: 10.1016/s0378-4320(01)00155-5
Batellier F, Vidament M, Fauquant J, Duchamp G, Arnaud G, Yvon JM, Magistrini M.In the horse industry, milk or milk-based extenders are used routinely for dilution and storage of semen cooled to 4-8 degrees C. Although artificial insemination (AI) with chilled and transported semen has been in use for several years, pregnancy rates are still low and variable related to variable semen quality of stallions. Over the years, a variety of extenders have been proposed for cooling, storage and transport of stallion semen. Fractionation of milk by microfiltration, ultrafiltration, diafiltration and freeze-drying techniques has allowed preparation of purified milk fractions in ord...
Low dose insemination of mares using non-sorted and sex-sorted sperm.
Animal reproduction science    December 18, 2001   Volume 68, Issue 3-4 279-289 doi: 10.1016/s0378-4320(01)00165-8
Lindsey AC, Bruemmer JE, Squires EL.Mares are generally inseminated with 500 million progressively motile fresh sperm and approximately 1 billion total sperms that have been cooled or frozen. Development of techniques for low dose insemination would allow one to increase the number of mares that could be bred, utilize stallions with poor semen quality, extend the use of frozen semen, breed mares with sexed semen and perhaps reduce the incidence of post-breeding endometritis. Three low dose insemination techniques that have been reported include: surgical oviductal insemination, deep uterine insemination and hysteroscopic insemin...
Advances in cooled semen technologies: seminal plasma and semen extender.
Animal reproduction science    December 18, 2001   Volume 68, Issue 3-4 171-180 doi: 10.1016/s0378-4320(01)00154-3
Rigby SL, Brinsko SP, Cochran M, Blanchard TL, Love CC, Varner DD.This study evaluated motility and fertility of uncentrifuged and centrifuged equine semen following dilution in a skim milk-glucose extender with or without supplemental Tyrode's medium. In addition, the effect of seminal plasma addition to each extender was evaluated. For Experiment 1, motility of 48h cooled, stored spermatozoa was evaluated following eight dilution treatments: uncentrifuged and diluted 1:4 (v/v) in skim milk-glucose extender (EZ Mixin CSTJ; CST-1:4) or in CST supplemented 65:35 (v/v) with modified Tyrode's medium (KMT-1:4); uncentrifuged and diluted to 25x10(6) spermatozoa/m...
Effects of acute intravenous aldosterone administration on Na(+), K(+), and water excretion in the horse.
Journal of applied physiology (Bethesda, Md. : 1985)    December 18, 2001   Volume 92, Issue 1 135-141 doi: 10.1152/jappl.2002.92.1.135
Jansson A, Lindholm A, Dahlborn K.The effect of a temporary increase in plasma aldosterone concentration on Na(+), K(+), and water balance was investigated in four horses. Aldosterone was injected intravenously for 6 h at 20-min intervals (total 5.4 microg/kg body wt). Samples were taken for 24 h before, during, and for 48 h after the treatment. Aldosterone treatment reduced the Na(+) loss via urine and feces by 99 and 72%, respectively, later followed by a marked increase in Na(+) excretion by both pathways. During the first 6 h after the treatment, fecal K(+) excretion was elevated, and the plasma K(+) concentration was lowe...
Oral imipramine and intravenous xylazine for pharmacologically-induced ex copula ejaculation in stallions.
Animal reproduction science    December 18, 2001   Volume 68, Issue 3-4 153-159 doi: 10.1016/s0378-4320(01)00152-x
McDonnell SM.This study is part of ongoing work toward developing pharmacological methods for enhancing and inducing ejaculation in stallions with ejaculatory dysfunction or disabilities that interfere with normal breeding behavior. The objective was to evaluate a treatment regimen involving oral imipramine followed by intravenous xylazine that, in uncontrolled field clinical trials, had shown promise for a higher rate of ejaculation and fewer side effects using a more easily obtained and administered form of imipramine. Eight stallions each underwent eight trials in which treatment consisted of imipramine...
Feeding practices associated with colic in horses.
Journal of the American Veterinary Medical Association    November 29, 2001   Volume 219, Issue 10 1419-1425 doi: 10.2460/javma.2001.219.1419
Hudson JM, Cohen ND, Gibbs PG, Thompson JA.To determine whether specific feeding practices were associated with development of colic in horses. Methods: Prospective matched case-control study. Methods: 364 horses examined by veterinarians in private practice in Texas because of colic (cases; n = 182) or any other reason (controls; 182). Methods: Participating veterinarians were sent forms at the beginning of the study to collect information on signalment, feeding management practices, farm management practices, and preventive medical treatments. Case and control horses were compared by use of conditional logistic regression to identify...
Supplemental silicon increases plasma and milk silicon concentrations in horses.
Journal of animal science    November 28, 2001   Volume 79, Issue 10 2627-2633 doi: 10.2527/2001.79102627x
Lang KJ, Nielsen BD, Waite KL, Hill GM, Orth MW.The primary objective of this research was to determine the effect of supplemental dietary silicon (Si) on plasma and milk Si concentrations of lactating mares and the subsequent effect on plasma Si concentrations in nursing foals. Additionally, the role of Si on altering biochemical markers of bone turnover was investigated, because supplemental Si may be advantageous in enhancing bone health. Twelve Arabian mare/foal units were pair-matched by foaling date and randomly assigned to two groups, Si-supplemented (Supplemented) or control (Control). Blood and milk samples were taken on d 0, 15, 3...
Listeria keratitis in a horse.
Veterinary ophthalmology    November 28, 2001   Volume 4, Issue 3 217-219 doi: 10.1046/j.1463-5216.2001.00179.x
Sanchez S, Studer M, Currin P, Barlett P, Bounous D.Listeria monocytogenes is ubiquitous in the environment but is rarely reported as a cause of keratitis in animals. In this case, a mare was presented with epiphora and evidence of pain in the right eye. Listeria monocytogenes was isolated from a corneal lesion, and bacteria were also seen in the cytologic evaluation. This is the first reported case of ulcerative keratitis associated with L. monocytogenes in a horse.