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.
Dean PW, Robertson JT, Jacobs RM.In 7 horses, 4 anastomoses were done in the small intestine in each, using the combinations of synthetic absorbable monofilament and multifilament suture materials with continuous- and interrupted-suture patterns in the serosubmucosal layer of a 2-layer inverting-suture technique. Horses were evaluated 30 days after the operation for adhesion formation, lumen diameter, evidence of chronic obstruction, and suture tract inflammation at the anastomosis. Postoperative obstruction occurred in 5 of the 7 horses, and 6 horses survived. One horse was euthanatized on postoperative day 6 after 48 hours ...
Halliwell RE, Brim TA, Hines MT, Wolf D, White FH.An enzyme linked immunosorbent assay was developed for the detection of immunoglobulin class specific antibodies to Leptospira interrogans serovar pomona in the serum and aqueous humor of horses. Serum antibody was also assayed by microscopic agglutination tests. Although higher levels of antibody were found in sera from horses with signs of uveitis, the association was not statistically significant. Antibodies to pomona were detected in the aqueous of 12 eyes from the 101 horses sampled at a slaughterhouse, and in most instances, a comparison of the aqueous/serum antibody level with that of t...
Halliwell RE, Hines MT.A radioimmunoassay was developed for detection of immunoglobulin in the aqueous of normal horses and horses with intraocular diseases. Levels of albumin were detected by radial immunodiffusion. Results of assays on samples from normal eyes from which aqueous was obtained by paracentesis under anesthesia were 32.10 +/- 21.50 microgram/ml for IgG, 0.05 +/- 0.01 microgram/ml for IgM, 0.04 +/- 0.02 microgram/ml for IgA and 34.0 +/- 38.0 microgram/ml for albumin. Results in 138 normal eyes sampled post mortem were 41.56 +/- 38.65 microgram/ml for IgG, 0.18 +/- 0.43 microgram/ml for IgM, 0.46 +/- 1....
Srivastava SK, Barnum DA.The ability of either formalin-treated or heat-inactivated whole Streptococcus equi cell vaccines or partially purified M-protein of S. equi to give rise to protective antibody levels was studied in Standardbred foals by serological means. Two commercial preparations, i.e. a beta-propiolactone killed whole S. equi cell bacterin and a cell-free extract of S. equi cells were included in the study. The mean passive hemagglutination antibody titers (10 X log2) in sera of foals given either four doses of formalin-treated whole cell vaccine or an initial dose of formalin-treated followed by three do...
Forster HV, Pan LG, Flynn C, Bisgard GE, Hoffer RE.We determined whether the [CO2] in the upper airways (UA) can influence breathing in ponies and whether UA [CO2] contributes to the attenuation of a thermal tachypnea during periods of elevated inspired CO2. Six ponies were studied 1 mo after chronic tracheostomies were created. For one protocol the ponies were breathing room air through a cuffed endotracheal tube. Another smaller tube was placed in the tracheostomy and directed up the airway. By use of this tube, a pump, and prepared gas mixtures, UA [CO2] was altered without affecting alveolar or arterial PCO2. When the ponies were at a neut...
Rhodes JB, Schweitzer D, Ogg JE.Non-O1 Vibrio cholerae was isolated from a horse (Equus caballus), a lamb (genus Ovis), and two American buffalo (Bison bison) suffering from enteric disease in the western part of Colorado. In 1981, a foal died of apparent respiratory failure. Necropsy findings included heart failure and gastroenteritis. V. cholerae serovar 347 (Smith) was isolated from the colon of this animal. V. cholerae serovar 27 (Smith) was isolated in 1983 from the intestine of a feedlot lamb suffering from pneumonia and severe watery diarrhea. In 1984, an enteric disease occurred in a herd of American bison. The sick ...
Flynn C, Forster HV, Pan LG, Bisgard GE.The objective of this study was to determine the role of hilar nerve (lung vagal) afferents in the hyperpnea of exercise. Ten ponies were studied before and 2-4 wk and 3-12 mo after sectioning only the hilar branches of the vagus nerves (HND). After HND, lung volume feedback to the medullary centers was attenuated as indicated in the anesthetized state by 1) attenuation or absence of the Hering-Breuer inflation reflex (P less than 0.01) and 2) attenuation of the lengthened inspiratory time (TI) when the airway was occluded at end expiration (P less than 0.01). Moreover, after HND in the awake ...
Martin GS, McIlwraith CW.Arthroscopic anatomy of the equine intercarpal and radiocarpal joints was documented in six cadaver limbs and on observations made during surgical treatment of horses with carpal osteochondral fractures. Instrument positions and arthroscopic visualisation were recorded. The cadaver limbs were dissected and iatrogenic lesions recorded. A single arthroscopic portal examination was adequate in both joints; however, a second arthroscopic portal improved visualisation. The intercarpal joint was more easily examined than the radiocarpal joint because of anatomical differences. Iatrogenic lesions wer...
Crandell RA, Davis ER.The virus causing equine coital exanthema (equine herpesvirus 3) was isolated from a lesion on the nostril of a 2-month-old foal. One week after the mare had returned from a stallion station, vesicular lesions developed on her vulva. They were diagnosed clinically as coital exanthema, and 5 days later a lesion developed on the nostril of her foal. This case is an example of horse-to-horse transmission of coital exanthema virus without coitus. A laboratory diagnosis is necessary to differentiate viruses that cause vesicular lesions about the oral and nasal cavities of horses.
Beech J, Irby N.Congenital cataracts affecting the fetal and embryonal lens nucleus were found in 12 Morgan horses. Ten of the 12 affected animals were sired by the same stallion and the condition also affected his female half sibling. Although females were almost three times more likely to be affected than males (9 vs 3), the difference was not significant. The ratio of 11 normal to 10 affected offspring by the affected stallion is compatible with an autosomal dominant mode of inheritance.
Romagnano A, Richer CL.Cell synchronization was used to obtain an adequate percentage of very long chromosomes in equine mitotic spreads. Reported here is our variation, adapted to horse chromosomes, of a method using excess thymidine followed by bromodeoxyuridine incorporation. This technique routinely yields excellent quality cells, predominantly in prometaphase and prophase. Among other differences with the standard technique, this method does not use Colcemid, which, in addition to inhibiting spindle fiber formation, also increases chromosome contraction resulting in thicker and thus fewer bands. Consequently, h...
Nolan AM, Hall LW.The use of propofol, solubilised in a non-ionic emulsifying agent, for the induction and maintenance of anaesthesia in experimental ponies was assessed. Pilot studies revealed that premedication with xylazine (0.5 mg/kg bodyweight [bwt]) intravenously (iv) followed by propofol (2.0 mg/kg bwt) iv provided a satisfactory smooth induction. Two infusion rates (0.15 mg/kg bwt/min and 0.2 mg/kg bwt/min) were compared for maintenance of anaesthesia. An infusion rate of 0.2 mg/kg/min produced adequate anaesthesia in these ponies. Cardiovascular changes included a decrease in arterial pressure and card...
Denny JE.Weekly blood serum samples from 20 yearling horses, divided into equal groups, receiving diets with total calcium to inorganic phosphorus ratios of 1,5/1 and 0,2/1, were analysed for calcium and phosphorus concentrations. This was done over a continuous 23 week period, divided into 2 sub-periods of 16 and 7 weeks each. During the first period complete diets were provided ad lib but were restricted during the second period to accentuate any effects of calcium deficiency and phosphorus excess. Falling calcium levels and rising phosphorus levels during period 1 and a reverse trend during period 2...
Kvart C, Carlsten J, Jeffcott LB, Nilsfors L.M-mode echocardiography is a safe and practical means of using ultrasound to evaluate the dynamic movements of cardiac structures. The technique can be refined by using a simple contrast medium in the form of carbon dioxide mixed with heparinised blood to provide a strong echogenic result. This technique was employed in a series of 15 normal conscious standing horses and in three animals with specific cardiac defects. In the clinical cases it was possible to confirm the diagnosis and differentiate between a congenital septal defect and mitral regurgitation. The method was found to be safe and ...
Jann HW, Cook WR.Monopolar electrosurgical cutting was used to correct epiglottal entrapment in 5 horses. The operations were carried out in the conscious animal, using topical anesthesia. The procedure required the use of a coagulation electrode designed specifically for electrosurgery, introduced through the instrument channel of a fiberoptic endoscope. The results were satisfactory and serious complications were not encountered. In 2 horses, excessive submucosal swelling developed at the site of the surgical wound, and the tumefaction took several weeks to subside in one of these horses. In both horses, the...
Monath TP, Sabattini MS, Pauli R, Daffner JF, Mitchell CJ, Bowen GS, Cropp CB.Serologic surveys of wild and domestic birds, wild mammals, and horses were conducted during arbovirus field studies in Argentina from 1977 through 1980, a non-epizootic interval. The prevalence of neutralizing antibodies to eastern equine encephalitis (EEE) was consistently higher than to western equine encephalitis (WEE) virus in all species and all areas. The presence of antibodies in short-lived avian species and in young unvaccinated horses and the demonstration of seroconversions in horses during the period, indicated that these viruses are either enzootic in, or annually reintroduced in...
Little PB, Thorsen J, Moore W, Weninger N.Powassan virus strain M794, a member of the Flavivirus genus known to infect man and animals in Canada, was inoculated intracerebrally into rabbits and horses. No clinical signs were observed in rabbits, but widespread encephalitis resulted, characterized by lymphoid perivascular cuffing, lymphocytic meningitis, and lymphocytic choroiditis. In horses, eight days after inoculation, prominent neurological signs occurred and lesions were those of non-suppurative encephalomyelitis, neuronal necrosis, and focal parenchymal necrosis. The virus could not be reisolated from the rabbit or horse brains....
Sabattini MS, Monath TP, Mitchell CJ, Daffner JF, Bowen GS, Pauli R, Contigiani MS.This is the introductory paper to a series on the ecology of arboviruses in Argentina. Epizootics of equine encephalitis have occurred since at least 1908, principally in the Pampa and Espinal biogeographic zones, with significant economic losses; human cases of encephalitis have been rare or absent. Both western equine and eastern equine encephalitis viruses have been isolated from horses during these epizootics, but the mosquitoes responsible for transmission have not been identified. A number of isolations of Venezuelan equine encephalitis (VEE) virus were reported between 1936 and 1958 in ...
Rikihisa Y, Perry BD, Cordes DO.Potomac horse fever is characterized by fever, anorexia, leukopenia, profuse watery diarrhea, dehydration, and high mortality. An ultrastructural investigation was made to search for any unusual microorganisms in the digestive system, lymphatic organs, and blood cells of ponies that had developed clinical signs after transfusion with whole blood from horses naturally infected with Potomac horse fever. A consistent finding was the presence of rickettsial organisms in the wall of the intestinal tract of these ponies. The organisms were found mostly in the wall of the large colon, but fewer organ...
Rossdale PD, Jeffcott LB, Leadon DP.The development and design of a project in collaborative research which originated from a problem identified in practice, namely prematurity in the newly born foal, is described here. The project established a model of equine prematurity for the purpose of studying the diagnosis, pathogenesis and treatment of the condition. It involved practitioners and full time research workers in a number of veterinary and medical institutes.
van Miert AS.A study of the literature was done because of questions asked in a court of justice concerning possible poisoning in a jumper, resulting from administration of both phenylbutazone and a coumarin derivative within a particular period. In view of the mechanisms of action and the pharmacokinetic characteristics of the agents, these forms of combined treatment are also highly inadvisable in horses.
van den Bogaard AE, Thijssen HH, Hemker HC.The anticoagulant, warfarin, has been reported to be effective as treatment for navicular disease in horses. Since other forms of treatment for this disease are palliative, this new anticoagulant therapy has become widely employed. Despite the fact that initiation of anticoagulant therapy is relatively simple, attending veterinary practitioners should be aware that careful monitoring of this therapy is required for both safety and efficacy. Navicular disease is an example of equine thrombotic disease, and the goal of warfarin therapy is the prevention of new thrombus formation, while at the sa...
Koblik PD, Hornof WJ.Survey thoracic radiography, although limited by physical considerations in the adult horse, can supply clinically useful information about changes in cardiac size and function. The radiographic features of cardiomegaly, altered pulmonary circulation, pulmonary edema, and pleural effusion as manifested in the horse are discussed. Nuclear cardiology can be performed in the standing horse. The initial transit of a radioactive tracer through the central circulation provides information about cardiac chamber size, efficiency of ventricular contraction, valvular competence, and presence of intracar...
Agrawal K, Ebel JG, Bischoff K.Most antidoping method development in the equine industry has been for plasma and urine, though there has been recent interest in the analysis of synovial fluid for evidence of doping by intra-articular corticosteroid injection. Published methods for corticosteroid analysis in synovial fluid are primarily singleplex methods, do not screen for all corticosteroids of interest and are not adequately sensitive. The purpose of this study is to develop a rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS-MS) screening method for the detection of four of the most common intra-a...
Takafuji VA, Howard RD, Ward DL, Sharova LV, Crisman MV.The effect of recombinant equine IL-1beta (EqIL-1beta) on steady-state mRNA levels of equine articular chondrocytes in high-density monolayer culture was investigated using a customized cDNA array analysis. Total RNA samples isolated from chondrocytes cultured in media alone or with the addition of 1 ng/ml EqIL-1beta for 1-, 3-, and 6-h durations of exposure were reverse transcribed, radiolabeled, and hybridized to a customized 380-target cDNA array. Means of duplicate log base 2 transformed hybridization signals were normalized to equine glyceraldehyde 3-phosphate dehydrogenase (GAPDH) mean s...
Koblik PD, Hornof WJ.Survey thoracic radiography, although limited by physical considerations in the adult horse, can supply clinically useful information about changes in cardiac size and function. The radiographic features of cardiomegaly, altered pulmonary circulation, pulmonary edema, and pleural effusion as manifested in the horse are discussed. Nuclear cardiology can be performed in the standing horse. The initial transit of a radioactive tracer through the central circulation provides information about cardiac chamber size, efficiency of ventricular contraction, valvular competence, and presence of intracar...
Peyton LC, Connelly MB.Bacterial quantification was evaluated in 15 cases as a means of wound assessment. This study suggests that bacterial quantification may be used as an aid in the evaluation of treatment procedures and wound preparation in veterinary surgery.
Lyons ET, Drudge JH, Tolliver SC.Activity of ivermectin, administered IM at the dosage rate of 200 micrograms/kg of body weight, was evaluated in controlled tests against migrating larvae of Strongylus vulgaris and adult Trichostrongylus axei in experimental infections in 6 ponies raised worm-free. Ponies were given 2,190 or 2,400 infective 3rd-stage larvae of S vulgaris at 7 days before treatment and 22,000 or 22,750 infective 3rd-stage larvae of T axei at 42 or 45 days before treatment. Three ponies were given ivermectin plus vehicle, and 3 ponies were given the vehicle only; the ponies were euthanatized 7 or 9 days after t...
van Galen G, Cassart D, Sandersen C, Delguste C, Nollet H, Amory H, Ducatelle R.Polyneuritis equi (PNE) is a rare neurological disease in the horse. Because of the suspicion in PNE of a T-lymphocyte mediated immune response against the myelin, the objective of this study was to determine the composition of the inflammatory infiltrate in the involved nerves of 3 horses with PNE, studied retrospectively. T-lymphocytes were demonstrated in the lesions, which suggests a T-lymphocyte mediated immune response against myelin. In addition, the presence of B-lymphocytes indicated a local production of antibodies. More research, involving a prospective study, is needed to determine...