Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Dutta SK.An adenovirus was isolated from a foal with respiratory tract disease. The virus produced cytopathic effects (CPE) in equine embryo kidney (EEK) cell culture, contained deoxyribonucleic acid (DNA), was resistant to chloroform and pH 3, and was moderately resistant to heat. The virus caused hemagglutination of human (type O) erythrocytes. Viral density was 1.34 g/cm,3 and diameter was 75 nm. An adenovirus-associated virus (AAV) isolated from the infected cell culture was 22 nm in diameter. These viruses are classified as equine adenovirus and equine AAV.
Banks KL, McGuire TC.Surface receptors on peripheral blood neutrophils and monocytes from normal and immunodeficient horses have been studied. Sheep erythrocytes (SRBC) coated with IgG, IgM, and complement but not IgG(T), readily bound to normal equine monocytes and neutrophils. More than 4000 molecules of IgG were required to sensitize each SRBC for adherence to monocytes, and more than 12,000 molecules were required for adherence to neutrophils. Young horses with a severe combined immunodeficiency had an almost total absence of lymphocytes, but normal numbers of monocytes and neutrophils. The number of receptors...
Duncan JL, Dargie JD.The migratory route of infective Strongylus vulgaris larvae was determined: penetration of small and large intestine into the lumina of submucosal arteries, migration up the arterial tree, reaching the cranial mesenteric site by three weeks, where the larvae develop to the mature 4th stage. After 3-4 months they exsheath and the young adults migrate down the arteries towards the intestines, to the limit of arterial narrowing, from where they rupture from nodules into the lumen of the intestine. The prepatent period is about 6 months. The clinical syndrome was similar to, but less severe than t...
Schryver HF.Recent knowledge regarding the absorption of calcium and phosphorus from the intestine of the horse has been reviewed. Consideration has been given to sites, mechanisms and factors affecting absorption as well as to the availability of calcium and phosphorus from feedstuffs commonly used in Eastern North America. Although the anatomy of the digestive tract might appear to impose restrictions on the ability of the horse to assimilate minerals, studies of absorption show that the horse utilizes the calcium and phosphorus of many feeds very efficiently.
Thompson DB, Studdert MJ, Beilharz RG, Littlejohns IR.A fatal syndrome of certain Arabian foals which begins at about 25 days of age (range 14 to 46 days) and which runs a course of about 23 days (range 13 to 42 days) is described. The syndrome, which affected 17 foals on a single farm is further characterised by pneumonia, in some instances by dermatitis (dermatophilosis) and other infections, together with a progressive decline in health till death at about 49 days of age (range 34 to 77 days), despite intensive therapy. Four of the foals, on histopathological evidence, had adenviral pneumonia, in 2 foals there was histopathological evidence of...
Azzie MA.Contrary to common belief, Gastrodiscus aegyptiacus can be pathogenic to horses. History of cases of a particular stud, necropsy findings, diagnosis, and successful treatment with hexachlorophene and with dichlorvos are recorded. The presence of eggs can be established by a special flotation technique.
Yagisawa S.One mole of horse hemoglobin tetramer reacts with 2 moles of 2-chloromercuri-4-nitrophenol (MNP) at beta 93 cysteine. The difference spectra between NMP-bound hemoglobin and hemoglobin, measured with the aid of ascorbic acid and ascorate oxidase [EC 1.10.3.3] as deoxygenation reagents, indicate that the pK of the phenolic hydroxyl group of MNP increases by 0.6 to 0.8 pH unit on deoxygenation of the hemoglobin. The Hill constant of the modified hemoglobin changes with pH. It decreases from about 2.4 at pH 6.8 to about 1.0 at pH 9.0 This effect of the reagent is interpreted as inherent to the re...
Donawick WJ.The horse with an abdominal crisis caused by acute gastro-intestinal tract obstruction develops hypovolaemia, haemoconcentration, electrolyte depletion, metabolic acidosis and shock. During preparation for operation, treatment with fluids, antibiotics and bicarbonate will impede metabolic imbalance. Stomach decompression may slow the passage of sodium, water and potassium to the gut lumen, reduce pain and minimize the risk of stomach rupture. Selected laboratory determinations and the monitoring of arterial and venous pressures will provide a measure of security, and serve as a guide to replac...
Coffman JR.Initial examination and therapy, and the avoidance of maltreatment are emphasized. Gastric decompression is of prime importance, after which no compound should be administered via stomach tube. Where large amounts of high starch grains are fed, primary acute gastric dilatation must be differentiated from that secondary to small bowel dilatation, by immediate gastric intubation and irrigation of the cardia with lidocaine. If cessation of pain and improvement of peristalsis and general attitude follow, the former state may be assumed. If pain persists and peristalsis does not improve markedly, o...
Boles C.Adequate post-operative management of equine abdominal patients is as necessary to patient survival as the most heroic corrective surgery. Post-operative management must begin during the anaesthesia recovery phase to insure adequate oxygen supply, ventilation, and minimize any abdominal discomfort. The animal's physiological status must be constantly monitored to detect and determine the degree of abnormalities concerning serum electrolytes, fluid balance, and acid-base abnormalities. The most commonly observed serum electrolyte imbalance is hypokalaemia. Replacement potassium is usually suppl...
Van der Merwe JA.The revised NRC's Nutrient Requirements of Horses is changing the outlook on equine nutrition, dominated for so long by the traditional belief in oats. This has lead to the need for properly balanced diets, in the compounding of which dietary cubes offer the distinct advantage of providing a standardized diet of constant quality in keeping with modern knowledge. Additional factors are: longer storage, freedom from dust, palatability, refractoriness to mould infection, and facilitation of routine feeding. Cube size and hardness are important considerations for the manufacturer. Horses appear to...
Merritt AM, Bolton JR, Cimprich R.Pertinent questions regarding the history of a horse with diarrhoea are listed, as are diagnostic procedures that might be included in a complete clinical work-up. For purposes of discussion, diarrhoea is regarded as "acute" or "chronic" wherein the former concerns cases where the features of the disease are severe with progressive electrolyte imbalance, dehydration, toxaemia, or other life-threatening manifestations and the latter refers to cases that have been prolonged for a month or more. Patterns of disease, including results of diagnostic techniques, are stressed. In the "acute" category...
Villasmil DP, De Siger J, Barrientos MP, Mussgay M, Mackenzie RB.
Summary
Seven donkeys were immunized with a Venezuelan equine encephalitis virus vaccine which had been prepared by inactivation of the virus with formalin and Tween-80-Tri(n-butyl)phosphate and addition of saponin. Fourteen days later they, and four non-vaccinated controls, each received 50,000 suckling mouse intraperitoneal LD50 units of challenge virus. None of the seven immunized donkeys demonstrated signs of clinical illness or viremia. Of the four non-vaccinated controls, all became ill and one died. These results suggest that more extensive experiments might well be carried out on ...
Hintz HF.Recent studies on the digestive physiology of the horse are reviewed. It was suggested that the small intestine is the primary site of digestion and absorption of protein, soluble carbohydrates, most minerals, fats, fat soluble and water soluble vitamins. The large intestine is the primary site of fibre digestion and net water absorption. Significant amounts of phosphorus are also absorbed from the large intestine. Many factors such as rate of passage, processing of feeds, level of intake, work and maturity of plant may influence digestive ability.
Apukhovska LI, Vendt VP, Ivashkevych SP.Sterols of the whole erythrocytes, hemoglobin, membranes and their protein fractions were studied. Erythrocytes and their components were established to contain, besides cholesterol, other substances of the sterol nature. Cholesterol, 7-dehydrocholesterol and other substances of the cholesterol series are practically completely linked with the lipoproteid fractions of the erythrocyte membrane whereas all sterols found in the native erythrocytes in negligible amounts are bound with hemoglobin.
Drudge JH, Lyons ET, Tolliver SC.Controlled tests of the efficacy of bot-active compounds, dichlorvos, trichlorfon, trichlorfon butonate, and carbon disulfide on the larvae of Gasterophilus intestinalis and Gasterophilus nasalis during their migratory period in the tissue of the mouth of horses and ponies were completed on experimentally induced and naturally acquired infections. Against the experimental parasitisms in pony foals, the resin-pellet formulation of dichlorvos given on the feed at the dose level of 37 mg/kg, 2 formulations of trichlorfon given by stomach tube at the dose level of 40 mg/kg, another of trichlorfon ...
Rhim JS, Ro HS, Kim EB, Gilden RV, Huebner RJ.A horse skin cell line (E. Derm, NBL-6, CCL-57) was susceptible to focus formation by the Kirsten mouse sarcoma virus, feline sarcoma virus (ST stain) and the MSV pseudotypes with woolly monkey, gibbon monkey, RD-114, AT-124, baboon placenta and murine xenotropic (BALB/c 3T3 and C57L/JD) type-C viruses. Foci were detected within 5 days after infection and the transformed cells continued to produce infectious virus and group-specific antigen of their respective type-C leukemia viruses. The transformation efficiency of various type-C sarcoma viruses in horse cells was also very high.
Brand A, de Bois CH, Vandenhende R.Parenteral administration of 2.5-5 mg. of prostaglandin F2alpha to horses, 15 mg. to heifers or 25-30 mg to lactating cows and 15 mg. to sheep will induce regression of the corpus luteum (luteolysis) and a fertile oestrus within 48-72 hours. Because of their luteolytic effect prostaglandins may be used in various indications in the field of reproduction. An exception is the pig in which administration of prostaglandins does not induce luteolysis before D12 and therefore fails to induce oestrus. In horses, cattle and sheep, administration of prostaglandins during the first four days of the cycl...
Haywood L, Spike-Pierce DL, Barr B, Mathys D, Mollenkopf D.Incomplete ossification of the cuboidal bones of the carpus and tarsus in foals has the potential for significant consequences including chronic lameness and decreased athletic ability. Objective: To determine if the degree of ossification of the cuboidal bones is associated with gestational length and if the diagnosis of incomplete ossification is a predictor of performance in Thoroughbred racehorses. Methods: Retrospective cohort study. Methods: The medical records of Thoroughbred foals less than 90 days of age from 1994 to 2011 were examined and records containing tarsal radiographs identif...
Wheat JD, Pascoe JR.Problems involving the management of acute traumatic rupture of the equine suspensory apparatus include loss of blood flow to the foot, proper immobilization, and pressure sores from casts. A technique utilizing a board splinting device attached to the affected limb at the toe and subsequent corrective shoe support provides immobilization, prevents dropping of the fetlock, can be applied to the standing animal, and allows frequent changing of the bandages, if necessary.
Kappe EC, Köhler K, Felbert IV, Teifke JP, Tóth J, Reinacher M.A 14-year-old Haflinger gelding presented with a protruding mass involving the cornea of the right eye. The mass was resected and submitted for histopathologic and immunohistochemical examination. The preliminary diagnosis was corneal sarcoma, most likely fibrosarcoma. The immunohistochemical results confirmed the mesenchymal origin of the neoplastic cells, which were most consistent with a malignant peripheral nerve sheath tumor. Corneal mesenchymal neoplasms are extremely uncommon tumors in human beings and domestic animals. The cause for this tumor was not determined; infection with bovine ...
Hahn C.The neurological examination is undertaken to determine whether any deficit is due to a lesion in the nervous system and, if so, where within the nervous system any possible lesion or lesions are located. The examination of horses has challenges not encountered when doing the equivalent examination in dogs and cats, principally that spinal reflexes and postural reactions are impossible/difficult to assess in most animals. The anatomy book can be consulted later but at the end of the neurological examination the clinician then should be able to determine broadly which area of the neuromuscular ...
Etherington WG, Vasey JR, Horney FD.Two cases of ethmoid hematoma of the equine are reported. Clinically both horses had intermittent unilateral epistaxis unassociated with exercise. In one horse, diagnosis was based on the use of an endoscope for visualization and for biopsy of a mass associated with the ethmoid turbinates. In the other horse, exploratory trephination of the posterior maxillary sinus was necessary to obtain a diagnostic biopsy specimen. Radiography was helpful in the diagnosis of one case. Surgical removal of the mass was attempted in one case. Histological examination of the biopsies was the single most defini...
Burns JJ, MacMillan KM, John EE.Atrial fibrillation (AF) is the most clinically relevant cardiac arrhythmia identified in the Standardbred racehorse. However, there is limited literature regarding athletic ability in Standardbred racehorses following AF conversion. To investigate this issue, the objectives of this review were to: i) determine the success rate in using quinidine sulphate to treat AF in a population of hospitalized equine patients in Atlantic Canada between January 2008 and December 2019; and ii) measure return to athletic ability (using racetrack earnings and top-3 finishes) following cardioversion with quini...
Kidd JA, Voute LC, Hewetson M.A 12-year-old hunter gelding became severely lame as a result of a laceration to the sheath of the digital flexor tendons of its left hindlimb, but there was no apparent damage to the tendons. The injury became chronically infected with Pseudomonas and Streptococcus species and Escherichia coli which did not respond to antibiotic treatment, and the horse remained lame. A postmortem examination revealed that the tendons had ruptured.
Lyons ET, Drudge JH, Tolliver SC.Two controlled tests (experiments D and E) were done to evaluate a fenbendazole (FBZ) paste dosage regimen (10 mg/kg once a day for 5 days) for activity against naturally occurring infections of migrating Strongylus vulgaris and S edentatus in the mesenteric arteries and ventral abdominal wall, respectively. Data were also obtained on other internal parasites of the gastrointestinal tract and eyes in experiment E. Eight pony yearlings were used in experiment D (4 treated and 4 nontreated) and 6 horse weanlings were used in experiment E (3 treated and 3 nontreated). Intervals, expressed as days...
Simpson JW, Else RW.Methods are described for the endoscopic examination and biopsy of the gastrointestinal tract and liver of the dog, cat, ox and horse. The results of the examination of 41 biopsy samples are shown, followed by a discussion of the value of biopsy in the diagnosis of diseases of the digestive tract.
Brown DR, Forster HV, Lowry TF, Forster MA, Forster AL, Gutting SM, Erickson BK, Pan LG.Breathing, diaphragmatic and transversus abdominis electromyograms (EMGdi and EMGta, respectively), and arterial blood gases were studied during normoxia (arterial PO2 = 95 Torr) and 48 h of hypoxia (arterial PO2 = 40-50 Torr) in intact (n = 11) and carotid body-denervated (CBD, n = 9) awake ponies. In intact ponies, arterial PCO2 was 7, 5, 9, and 11 Torr below control (P less than 0.01) at 1 and 10 min and 5 and 24-48 h of hypoxia, respectively. In CBD ponies, arterial PCO2 was 3-4 Torr below control (P less than 0.01) at 4, 5, 6, and 24 h of hypoxia. In intact ponies, pulmonary ventilation, ...
Marks D.The most common causes of back pain and their medical treatment are discussed. These include: dermatologic problems and conditions resulting from saddle trauma; discomfort and stiffness owing to injured paraspinal muscles; pain associated with supraspinous ligament damage; osseous pain and nerve dysfunction related to the spine and sacroiliac area; and neurologic diseases that can manifest as back pain. Bitting problems, cervical pain, and coexisting lameness are also considered.
Fitzgerald BP.The purpose of this experiment was to investigate whether N-methyl-D,L-aspartate stimulated gonadotropin secretion in mares and to determine the response in two experimental paradigms where gonadotropin secretion is low or elevated. In Experiment 1, conducted during the breeding season (summer), eight long-term ovariectomized mares were treated daily for 21 d with progesterone plus estradiol (n = 4) or oil vehicle. Beginning on Day 14, each mare received, in a randomized design on alternate days, an intravenous injection of either 0, 0.5, 1.0, or 5.0 mg/kg NMA. Treatment with NMA was not accom...