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.
Grippa E, Santini L, Castellano G, Gatto MT, Leone MG, Saso L.Ethyl acetate extracts of equine serum, containing 0-5 microg/ml of hydrocortisone (HYD), dexamethasone (DEX), oxyphenbutazone (OPB), indomethacin (IND), phenylbutazone (PB) and probenecid as internal standard, were evaporated with nitrogen, resuspended in methanol and analyzed by HPLC, using a C-18 column equilibrated with 51:49 acetonitrile-water, 0.1% trifluoroacetic acid, at 1 ml/min. The eluate was monitored at 254 nm. The selectivity (inter-assay C.V.<4%), sensitivity (limits of quantitation of 0.25 microg/ml for HYD, DEX and IND, 0.5 microg/ml for PB and 1 microg/ml for OPB, despite ...
de Vries AA, Glaser AL, Raamsman MJ, de Haan CA, Sarnataro S, Godeke GJ, Rottier PJ.Equine arteritis virus (EAV) is an enveloped, positive-stranded RNA virus belonging to the family Arteriviridae of the order Nidovirales. The unsegmented, infectious genome of EAV is 12,704 nt in length [exclusive of the poly(A) tail] and contains eight overlapping genes that are expressed from a 3'-coterminal nested set of seven leader-containing mRNAs. To investigate the importance of the overlapping gene arrangement in the viral life-cycle and to facilitate the genetic manipulation of the viral genome, a series of mutant full-length cDNA clones was constructed in which either EAV open readi...
Rakestraw PC, Snyder JR, Sanders KM, Shuttleworth WC.To evaluate electrical activity of jejunal circular muscle in horses and characterize electrical responses to stimulation by intrinsic inhibitory neurons. Methods: Portions of jejunum obtained from horses euthanatized for reasons other than gastrointestinal tract disease. Methods: Isolated circular muscle preparations were perfused with oxygenated modified Krebs solution. Glass microelectrodes were used for intracellular recording of membrane potentials from single smooth muscle cells. Electrical activity and responses to electrical field stimulation (EFS) of intrinsic neurons in the presence ...
King SS, Young DA, Nequin LG, Carnevale EM.To determine whether specific sugars inhibit adhesion of Streptococcus zooepidemicus, Pseudomonas aeruginosa, and Escherichia coli to equine endometrial epithelial cells in vitro. Methods: Endometrial biopsy specimens collected during estrus from 7 healthy mares. Methods: Endometrial specimens on glass slides were incubated for 30 minutes at 4 C with suspensions of S. zooepidemicus, P. aeruginosa, or E. coli in phosphate-buffered saline solution (PBSS) alone or with various concentrations of D-(+)-mannose, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, D-(+)-glucose, galactose, or N-acetyl-...
Roussel AJ, Hooper RN, Cohen ND, Bye AD, Hicks RJ, Bohl TW.To evaluate the effect of erythromycin on motility of the ileum, cecum, and pelvic flexure of horses during the postoperative and post-recovery periods. Methods: 8 healthy adult horses. Methods: Horses were anesthetized and bipolar electrodes were implanted in smooth muscle of the ileum, cecum, and pelvic flexure. Approximately 4, 16, and 24 hours (postoperative recording sessions) and at least 8 days (post-recovery recording session) after surgery, myoelectric activity was recorded before and after administration of erythromycin (0.5 mg/kg). Results: Following erythromycin administration, myo...
Frisbie DD, Sandler EA, Trotter GW, McIlwraith CW.To determine response of interleukin-1alpha (IL-1alpha)-conditioned equine articular cartilage explants to insulin-like growth factor-1 (IGF-1). Sample Population-Cartilage from the trochlea and condyles of the femur of a clinically normal 4-year-old horse. Methods: Effects of IGF-1 (0 to 500 ng/ml) after addition of IL-1alpha were evaluated by assessing matrix responses, using a sulfated glycosaminoglycan (GAG) assay, matrix 35SO4 GAG incorporation, and release of GAG. Mitogenic response was assessed by 3H-thymidine incorporation into DNA and fluorometric assay of total DNA concentration. Res...
Ikadai H, Kabamoto S, Xuan X, Igarashi I, Nagasawa H, Fujisaki K, Suzuki N, Mikami T.Babesia caballi merozoites were prepared by combining two improved methods of cultivation and purification of merozoites using Percoll-gradiation, and the protein compositions of merozoites were analyzed by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting. The relative molecular masses of the major proteins and protein masses separated by electrophoresis were >94, 80-70, 50-45, 34-30, 30-28 and 18 kDa. By Western blotting, twelve proteins or protein groups were recognized by pooled sera from two horses experimentally infected with B. caballi. Among...
Baptiste KE, Grahn BH.The clinical manifestations, laboratory findings, and survival times of 10 horses with orbital neoplasms are reported. In all cases, orbital neoplasms were malignant and locally invasive with no defined surgical circumscribed edges. It was often difficult to identify the primary cell type of the neoplasia in histologic specimens due to the poorly differentiated, anaplastic nature of the majority of cases. All except one horse were eventually euthanized 2 mo to 5 y after diagnosis due to poor response to treatment, metastasis, or unrelenting orbital neoplasia. Mean survival time increased with ...
Stanley SM.The metabolism and urinary excretion of a 100 mg dose of the non-sedating anxiolytic drug buspirone was examined using high-performance liquid chromatography/electrospray ionization mass spectrometry in the positive ion mode. In addition to a significant proportion of unchanged buspirone we were able to detect three major metabolite classes. These were identified as monohydroxy, dihydroxy and dihydroxymethoxy products. Detection of the metabolites and the parent drug was possible in all the urine samples collected (1-12 h) post-administration.
Cohen ND, Berry SM, Peloso JG, Mundy GD, Howard IC.To determine the association between high-speed exercise and risk of injury while racing among Thoroughbreds in Kentucky. Methods: Matched case-control study. Methods: 206 Thoroughbreds that sustained a musculoskeletal injury while racing and 412 Thoroughbreds that were not injured during the same races. Methods: Data regarding official timed workouts and races and the Beyer's numbers for the 3 races before the race during which injury occurred were extracted from past performance charts and compared between injured horses and control horses. Results: For injured horses, cumulative distance of...
Kellam LL, Johnson PJ, Kramer J, Keegan KG.Signs of mild colic, intermittent lethargy, and weight loss of 6 weeks' duration in a 2-year-old Quarter Horse gelding were attributed to persimmon (Diospyros virginiana) phytobezoar formation. Diagnosis of the phytobezoar was facilitated by gastric endoscopy. Signs of gastrointestinal tract obstruction were associated with a large phytobezoar in the lumen of the stomach, gastric ulceration, and obstruction of the small intestine (as a consequence of fragmentation of the primary bezoar). Conservative treatment, using mineral oil and dioctyl sodium sulfosuccinate, was unsuccessful. A celiotomy ...
Douglas JE, Thomason JJ.Circumferential and proximodistal variations in the morphology of the primary epidermal laminae of six neonatal and five adult equine feet were documented. Three parameters were quantified: interlaminar spacing, the orientation of the laminae with respect to the overlying wall, and any angulation within the laminae themselves ('internal angle'). In adult feet, the laminae were most closely spaced at the dorsum, the spacing increasing gradually towards the heels. In foals there was a non-significant trend for the dorsal laminae to be more widely spaced than those in more caudal parts of the foo...
Bureau F, Bonizzi G, Kirschvink N, Delhalle S, Desmecht D, Merville MP, Bours V, Lekeux P.Asthma is a chronic inflammatory disease of the airways, in which many inflammatory genes are overexpressed. Transcription factor, nuclear factor-kappaB (NF-kappaB), which is thought to control the transcriptional initiation of inflammatory genes, has been poorly investigated in asthma. In the present report, bronchial cells (BCs), recovered by bronchial brushing in healthy and heaves-affected horses (i.e., an animal model of asthma), were assessed for NF-kappaB activity. Small amounts of active NF-kappaB were present in BCs of healthy horses, whereas high levels of NF-kappaB activity was foun...
Fleury C, Bérard F, Balme B, Thomas L.The clinical and pathological characteristics of cutaneous melanomas occurring in Camargue-type gray-skinned horses are reported. Examination of 83 tumor-bearing horses revealed that the tumors occurred most frequently underneath the tail (93.9%) and at high rates in the peri-anal region (43.0%), the lips (33.0%), and the eyelids (24.0%), but rarely in the vulva (3.8%). Tumorous lesions were characterized by the presence of either hemispheric nodules or large infiltrated plaques, or their combinations. Microscopic examination indicated that tumorous lesions were composed mostly of melanocytes ...
Bailey SR, Andrews MJ, Elliott J, Cunningham F.Platelets are thought to play a role in equine diseases such as acute laminitis and verminous arteritis and may be involved in allergic disease. Mediators implicated in the pathophysiology of these conditions activate platelets and responses may be enhanced by interactions between mediators. The present study compared platelet aggregation, thromboxane production and release of radiolabelled [(3)H]5- HT in response to 5- HT, histamine, ADP and PAF alone and in combination in vitro.PAF caused concentration-related aggregation, [(3)H]5- HT release and thromboxane production. In contrast, ADP caus...
Kästner SB, Marlin DJ, Roberts CA, Auer JA, Lekeux P.The performance of a Fleisch No. 5 pneumotachometer (F), and two commercial ultrasonic pneumotachometers, the BRDL (B) and the Spiroson (S) systems were compared in respect to their use for determination of ventilatory parameters at rest and during lobeline-induced hyperpnoea. Five clinically healthy Thoroughbred horses were tested with the three pneumotachometers in random order. Respiratory airflow, respired gas concentrations, oesophageal pressures, pressures within the mask systems and arterial blood gases were determined before and during lobeline-induced hyperpnoea. Because measured peak...
Gray AW, Davies ME, Jeffcott LB.We report on novel methods to isolate osteoclasts (OC s) and generate osteoclast-like cells (OCL s) from the bone and bone marrow of the equine femur. OC s were successfully isolated from bone scrapings taken from the endosteal surface of the femurs of three horses. OCL s were generated from bone marrow cells taken from the same animals. The validity of using the formation of OCL s as a method for studying OC differentiation and activity was confirmed by the similar characteristics of these two cells. In particular, they both were multinuclear, expressed the enzyme tartrate resistant acid phos...
Lunn DP, Townsend HG.Equine infectious disease remains a constant and important threat to the health of domesticated horses. Vaccination plays a critical role in protecting against such disease, but at the present time the efficacy of some equine vaccination strategies is in doubt. The best strategy for resolving these concerns is an improved knowledge of the immunologic basis of successful vaccination, combined with the appropriate integration of effective vaccines into well-designed disease control policies.
Rush BR, Flaminio MJ.Nonspecific immunomodulators are substances that induce non-antigen-specific enhancement of the body's native or acquired defense mechanisms. Immunomodulant preparations are most often used for treatment of chronic, viral, or bacterial infection with evidence of secondary immunosuppression. The proposed mechanism of action of these products is macrophage activation and subsequent release of cytokines that enhance humoral and cell-mediated immunity. In equine medicine, nonspecific immunostimulant products are used for prevention and treatment of infectious respiratory disease and treatment of s...
McClure JT.Leukoproliferative disorders reported in horses include lymphoma, lymphocytic leukemia, plasma cell myeloma, granulocytic leukemia, monocytic leukemia, myelomonocytic leukemia, and eosinophilic leukemia. Lymphoma affects horses of all ages, whereas leukemias often occur in younger horses. Clinical signs are often nonspecific including depression, anorexia, fever, and weight loss. Specialized diagnostic techniques such as cytochemistry and immunophenotyping better define the cellular origin of leukoproliferative disorders, which is essential for developing appropriate therapeutic protocols and ...
Klei TR.Helminths are among the most significant parasites of horses in developed countries. This article examines immune responses against helminth parasites and the implications that immunologic investigations have on vaccine development, improvement of diagnostic procedures, and disease eradication.
Young KM, Lunn DP.Technologic advances in immunodiagnostic testing have enhanced our understanding of the pathogenesis of a broad array of diseases, including infectious diseases, immunodeficiency disorders, and immune-mediated disorders. If applied rationally, with an understanding of the questions the tests answer as well as the limitations that constrain their use, these tests can serve as valuable aids in the diagnosis and management of equine diseases.
Horohov DW.The ultimate reason for better characterizing the immune response to infectious agents is the hope that this knowledge may lead to the development of better preventative or therapeutic measures. As more information becomes available, it becomes possible to incorporate these findings into the design of better vaccines and treatments. Likewise, attempts to either enhance or suppress specific helper T-cell responses may be required to control immunopathologic reactions. Although cytokine intervention in the clinical setting remains theoretic at this time, future manipulation based on the TH1/TH2 ...
Giguère S, Prescott JF.The remarkable ability of the horse and other animals to prevent infection by most bacterial pathogens encountered is the result of a complex set of distinct but overlapping defense mechanisms. This article summarizes the current state of knowledge on innate and adaptive immunity to bacterial pathogens and reviews various ways in which some bacteria have evolved in order to evade components of the host response.
Perryman LE.Primary immunodeficiency disorders are genetically determined failures of immune defense that increase susceptibility to infectious agents. This article reviews the salient features of equine primary immunodeficiency disorders, summarizes the molecular mechanisms of each disorder, and updates information that facilitates diagnosis and management of affected horses. The central theme is to encourage clinicians to ask, "I wonder if this horse has an underlying primary immunodeficiency disorder?" when caring for horses suffering from chronic and recurring infections and responding poorly to stand...
McClure JJ.Although relatively little is known about autoimmunity and autoimmune mechanisms specifically in horses, the similarities between clinical syndromes with identifiable effector mechanisms in horses and other species suggest that comparable mechanisms may be applicable. Our understanding of equine autoimmunity undoubtedly will benefit from the extensive study of autoimmunity in other species.
Epstein V, Hodge D.Multiple cutaneous lymphosarcomas were diagnosed in an 8-year-old Thoroughbred stallion presented for evaluation of lumps on its scrotum. Histological examination of skin biopsy samples showed a homogenous pattern of lymphoid tissue suggestive of a T-cell lymphosarcoma. Immuno-histochemical tests showed a positive reaction to Rabbit/Anti-Human T-Cell, CD3 antibodies confirming T-cell lymphosarcoma. The animal was not treated and was subsequently euthanased.
Castelijns HH.Domesticated horses need hoof care, because it is rare for wear and growth of the hooves to be in perfect equilibrium. During the shoeing interval, the hoof grows downwards and forward in the direction of the horn tubules, losing some degree of angle. Few horses have perfect limb conformation. The shape of a hoof of a limb with conformation defects adapts in a predictable way. If, for therapeutic or performance reasons, the hoof-shoe combination is modified, there is a not a lot of leeway in the trim of a particular foot, whereas the applied shoe type, placement, and adjustments provide endles...
Widders PR, Stokes CR, Bourne FJ.The antigenic cross reactivity between equine IgG and IgGT was investigated. On the basis of immunodiffusion and immunoelectrophoresis reactions using an antiserum raised against the Fc fraction of IgGT, this equine immunoglobulin can be unequivocally classified as a subclass of IgG.
Ousey JC, Rossdalet PD, Palmer L, Grainger L, Houghton E.The aims of this study were to ascertain 1) whether fetal maturation could be induced precociously by maternal administration with adrenocorticotrophic hormone (ACTH) and 2) whether maturation could be achieved without significant risk to mare or fetus. Twenty-two mares received either 1 mg (low dose, LD, n = 6) or 4 or 5 mg (higher dose, HD, n = 16) synthetic Depot ACTH(1-24) at 300, 301 and 302 days gestation. Because, during the course of the study, ACTH appeared to have a greater influence on mares mated during the later part of the breeding season, the HD group were divided retrospectivel...
van Bergen T, Wiemer P, Bosseler L, Ugahary F, Martens A.Epiploic foramen entrapment (EFE) is, based on the number of reports in the literature, a relatively important life-threatening cause of colic in horses that could be prevented by closing the epiploic foramen (EF) in horses at risk of developing EFE. Objective: To describe the laparoscopic foramen epiploicum mesh closure (FEMC) technique and its outcome. Methods: Descriptive experimental study. Methods: The EF of 6 horses was closed with the FEMC technique. A diabolo-shaped constructed mesh was introduced into the omental vestibule through the EF under laparoscopic visualisation in the standin...
Paquette B.Equine infectious anemia in Canada was reviewed for the period January 1976 to December 1981. The human and ecological factors prevailing in Canada are deemed instrumental with respect to the evolution of the disease. The natural spread of the disease on a large scale has not been influenced by the Federal program. Reactors with signs of the disease are important for it's propagation. The author underlines the necessity of cooperation with private practising veterinarians to control it.
Rodriguez M, Hooghuis H, Castaño M.African horse sickness (AHS) is an infectious, non-contagious, highly fatal viral disease of Equidae, transmitted by arthropod vectors of the genus Culicoides, and endemic in Africa south and east of the Sahara. The disease is caused by a virus of the Reoviridae family, genus Orbivirus, and 9 serotypes have been recognized. Recent outbreaks of AHS in the Iberian peninsula and Northern Africa emphasize the need for accurate diagnosis and rapid implementation of control measures. In this paper, the epizootiological factors, clinical signs and necropsy findings of AHS are discussed, and an update...
Walker JE, Lewis CW, MacLeay JM, Kawcak CE, Wheeler DL.Functional relationships between articular cartilage and underlying subchondral bone have been shown to be associated with the progression of osteoarthritis (OA). However, quantifiable factors substantiating this relationship do not exist. Therefore, the study objective involved quantifying subchondral bone mineral density (BMD) of the equine metacarpophalangeal (MCP) and stifle joints as a step in determining if regional subchondral BMD may be associated with OA changes. BMD was bilaterally quantified using dual energy xray absorptiometry (DEXA) for four subchondral regions: palmer and dorsal...
Power HT, McEvoy EO, Manning TO.A 4-month-old foal was examined because of generalized exfoliative dermatitis, with thick scales, extensive crusting, and oozing of serum. A diagnosis of pemphigus foliaceus was made by histologic and immunopathologic examinations of skin biopsy specimens. The foal was treated with a gold compound, aurothioglucose (1 mg/kg once weekly for 14 weeks). For the initial 5 weeks, high-dose glucocorticoid treatments also was used. The skin disorder resolved entirely after 12 weeks of treatment.
Lunn DP, Townsend HG.Equine infectious disease remains a constant and important threat to the health of domesticated horses. Vaccination plays a critical role in protecting against such disease, but at the present time the efficacy of some equine vaccination strategies is in doubt. The best strategy for resolving these concerns is an improved knowledge of the immunologic basis of successful vaccination, combined with the appropriate integration of effective vaccines into well-designed disease control policies.