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.
Kaup FJ, Drommer W, Damsch S, Deegen E.Extensive light and electron microscope studies (transmission and scanning electron microscopy) of the bronchioles and alveolar region, in 28 horses suffering chronic obstructive pulmonary disease (COPD) and eight control horses, revealed good correlation between clinical severity and morphological changes. In the bronchiolar epithelium the non-ciliated bronchiolar epithelial (Clara) cells, in particular, showed ultrastructural alterations and, even in the mild stages of disease, these presented degenerative changes and lack of differentiation. Together with loss of granulation in the Clara ce...
Gossett KA, French DD, Cleghorn B, Church GE.L-Lactic acid and D,L-lactic acid infusion in ponies resulted in metabolic acidosis with high anion gap (AG). Increased AG was explained entirely by increased blood L- and D-lactate concentrations. Hydrochloric acid infusion caused metabolic acidosis with decreased AG. Saline (NaCl) infusion caused mild metabolic acidosis, with no significant change in AG. Plasma K+ concentration was decreased by all types of infusions, with a maximum of 0.50, 0.25, 0.40, 0.50 mmol/L below baseline at the end of infusion in the L-lactic acid-, D,L-lactic acid-, HCl-, and NaCl-infused ponies, respectively. Only...
Jasko DJ, Lein DH, Foote RH.Two commercially available computer-automate semen analysis instruments (CellSoft Automated Semen Analyzer and HTM-2000 Motion Analyzer) were compared for their ability to report similar results based on the analysis of pre-recorded video tapes of extended, motile stallion semen. The determinations of the percentage of motile cells by these instruments were more similar than the comparisons between subjective estimates and either instrument. However, mean values obtained from the same sample may still differ by as much as 30 percentage units between instruments. Instruments varied with regard ...
Hall LW, Young SS, Franklin RJ, Jefferies AK, Corke MJ.Investigations were carried out to determine whether measurements of total respiratory resistance (TRR) made in resting animals could detect changes due to laryngeal hemiplegia. Control values of TRR were obtained in eight ponies and in six of these the measurements were repeated after division of the left recurrent laryngeal nerve in the mid-cervical region; two were retained as controls. A further set of measurements were made before two of the operated animals were subjected to left laryngoventriculectomy (Hobday operation). A laryngoplasty ('tie-back' operation) was performed on another tw...
McKeever KH, Hinchcliff KW, Kociba GJ, Reed SM, Muir WW.Changes in clotting time (CT) and fibrinolytic activity (FA) were evaluated in 6 mature, female horses during exercise. Two trials were performed on consecutive days, using a randomized crossover design. Each mare was assigned to either an exercise trial or a control trial on the first day, and to the alternate trial 24 hours later. Mares exercised for 20 minutes on a treadmill at an elevation of 2 degrees and a velocity of 5 m/s. Venous blood samples were collected immediately before exercise, at 4, 8, 12, 16 and 20 minutes during exercise, and 15 minutes after cessation of exercise. Blood wa...
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...
Linden A, Art T, Amory H, Desmecht D, Lekeux P.Seven sport horses were investigated to compare physiological and pharmacological stresses on the plasma glucocorticosteroid levels. Venous blood was sampled and analysed for cortisol concentrations before and after each type of stress. The physiological stress was induced by the completion of a cross-country and the pharmacological one, by an intravenous ACTH administration (200 micrograms) in the same horses, one week after the course. Both exercise and ACTH injection induced a highly significant cortisol increase of 79 +/- 0.10% and 160 +/- 0.18%, respectively. The relative plasma cortisol ...
Bertone AL, Toofanian F, Stashak TS.Lactase, maltase, sucrase, and alkaline phosphatase activities were determined in the intestinal mucosa from 3 locations in the small intestine and 4 locations in the large intestine 1 year after extensive large-colon resection (group 1; n = 5) and 1 year after sham operation (group 2; n = 3) in horses. Lactase, maltase, and sucrase activities were similar (P greater than 0.05) between group-1 and group-2 horses in all locations measured in the intestinal tract. Alkaline phosphatase activity in the remaining large colon of group-1 horses was significantly (P less than 0.05) greater than the ac...
Wilson DG.Injuries involving full-thickness skin wounds are common in large animals. Skin grafting can shorten the healing time and improve the cosmetic result. Techniques that have been used successfully in the management of full-thickness skin wounds include full-thickness skin grafts, split-thickness skin grafts, tunnel grafts, pinch/punch grafts, and immediate split-thickness skin grafts. The technical aspects of each of these procedures are detailed and representative cases are presented.
Robertson SA, Steele CJ, Chen CL.The effect of general anaesthesia and arthroscopic surgery on blood glucose and lactate, plasma non-esterified fatty acids, insulin, beta-endorphin and cortisol was investigated in seven horses. Animals were premedicated with xylazine and anaesthesia was induced with guaifenesin and sodium thiamylal and maintained with halothane vaporised in oxygen. Blood samples were collected in the pre-, intra- and post operative period. Induction of anaesthesia was associated with a transient hyperglycaemia and a significant rise in plasma insulin levels. Plasma insulin values fell during surgery but showe...
Bauer JE, Meyer DJ, Campbell M, McMurphy R.Alterations in serum lipid and lipoprotein concentrations in ponies with experimentally induced liver disease were investigated. Hepatocellular damage was induced, using a nonlethal dose of carbon tetrachloride. In a separate group of ponies, obstructive jaundice was induced by surgical ligation of the common bile duct. Over a 6-day period, blood samples were obtained from ponies after treatment with carbon tetrachloride and for 12 days in ponies subjected to surgery. Serum cholesterol and triglyceride concentrations were unaffected in both groups of ponies, except for significantly (P less th...
MacAllister CG, Perdue BD.Unilateral ectopic ureter was diagnosed by endoscopic examination in an 18-month-old filly examined because of chronic urine dribbling. Intramuscular administration of azosulfamide discolored the urine and enhanced visualization of the ectopic ureter. Endoscopy proved valuable in determining that only one ureter entered the urinary bladder and in locating the ectopic ureter in the ventral portion of the vagina.
Martineau D, Bowser PR, Wooster G, Forney JL.Sixty-seven adult walleye fish were examined by light and transmission electron microscopy. The fish were affected by a mesenchymal tumor previously termed Walleye Dermal Sarcoma that commonly affects up to 27% of the population seasonally. Biopsies from 24 fish were collected, and complete postmortem examinations were performed on 43 fish. Grossly, the tumors had the appearance of randomly distributed, often clustered, spherical nodules, 2-5 mm in diameter with a smooth and often ulcerated surface. The tumors arose from the superficial surface of scales and consisted of fibroblast-like cells ...
Foerster RJ, Wolf G.Equine blood polymorphonuclear leukocytes (PMN) were isolated by buffy coat and hypotonic lysis of residual erythrocytes. A highly reproducible method is described for measuring the uptake of opsonized latex microspheres by equine PMN using flowcytometry. The use of cytochalasin D allowed for differentiation of ingested from attached particles. The kinetics of phagocytosis in vitro is shown for different experimental conditions. We developed an assay for evaluation of phagocytic capacity of PMN which allows the assessment of drugs for their influence on phagocytosis in vivo as well as in vitro...
Dice PF, Cooley PL.This report involves a retrospective study of five horses with an unusual form of progressive peripheral corneal ulcers. These ulcers were located at the perilimbal region of the cornea and spread both centripetally to mid periphery and circumferentially. Lipping of the epithelial edge was observed often. The depth ranged from superficial to mid stroma. Patients ranged from two and a half to eight years, both sexes, and were referred after a variety of antibacterial therapy. Histories were similar in that all ulcers were initially located adjacent to the limbus in one or more quadrants. No tra...
Grauerholz H.Interrelations between respiration and changes in amplitudes of the QRS-complex of the ECG of horses were investigated. The value of the R-vector and both its components Rx and Ry decrease during inspiration and increase in the expiration phase. It means, that the R-waves in leads from cranial to caudal (y, II, aVF) and from right to left (I) become smaller with inspiration and larger with expiration. The difference of the amplitudes may be important, especially in horses with respiratory problems, so that it has to be noted when evaluating electrocardiograms. For that purpose it is not necess...
Hodgson DR, Rose RJ, Kelso TB, McCutcheon LJ, Bayly WM, Gollnick PD.Thoroughbred horses were exercised to fatigue on a treadmill at 62% and 100% of their VO2max. Hypoxemia occurred at the onset of exercise under both exercise conditions. This hypoxemia persisted to fatigue during the heavy exercise but progressively diminished as the exercise continued and had disappeared by the end of exercise at the lighter load. As a result of the hypoxemia the oxygen content of arterial blood during exercise at VO2max was 17% below its carrying capacity. However, under both experimental conditions the CaO2 still exceeded that of rest owing to an elevation in hemoglobin con...
Simon F, Laczay P, Móra Z, Lehel J.The target animal safety of a dexamethasone-prednisolone combination was studied on 12 horses divided into two groups of six each. One group of horses received the therapeutic dose of the combination (25 mg/animal dexamethasone pivalate and 75 mg/animal prednisolone) and the second group was given the threefold dose of it. The preparation was administered intravenously for 2 consecutive days. For assessment of safety a wide range of clinical, haematological, biochemical and urine variables were tested as laid down in the guidelines of the FDA. All horses treated by the therapeutic or the three...
Bell K, Colling DT.An alloimmune reagent has been produced that distinguishes the equine factor Df in the D phenogroup, cfmqr, from that occurring in cefmqr and dfklr. Using this reagent it has been possible to correctly genotype Dc, d, f, k, l, m, q and r positive cells without recourse to family data.
Lepage OM, Hartmann DJ, Eicher R, Uebelhart B, Tschudi P, Uebelhart D.Concentrations of the cross-linked carboxyterminal telopeptide of type I collagen (ICTP) and osteocalcin (OC) have been determined in the serum of one hundred clinically healthy adult Draught or Warmblood horses. The correlation between these two markers has been evaluated and the influence of gender, age and type of horse described. No significant variations were observed between animals of different sex, but a significant inverse correlation (P < 0.0001) with age was observed for both measured parameters. After correction for age, serum levels of OC were found to be lower in Draught [adjuste...
Trist DG, Weatherall M.The research studies the effect of a drug called isoprenaline on the intake of a radioactive isotope, 86-Rb, in horse lymphocytes. It finds that isoprenaline has a significant effect increasing […]
Farchati H, Durand B, Marsot M, Garon D, Tapprest J, Sala C.It is essential to have an accurate picture of the spatial distribution of equines to be able to monitor equine health events effectively. In France, this information is only available for certain categories of live equines kept in professional structures and for dead equines removed by renderers. This limits the surveillance, prevention and control methods able to be used to prevent the spread of equine diseases. Our study aimed to provide a realistic estimate of the spatial distribution of the French equine population at the detailed scale of the French commune (France's smallest administrat...
Henry JS, Lance VA, Conlon JM.Within the order Perissodactyla, the primary structure of insulin has been strongly conserved. Insulin from Przewalski's horse and the mountain zebra (suborder Hippomorpha) is the same as that from the domestic horse and differs from insulin from the white rhinoceros and mountain tapir (suborder Ceratomorpha) by a single substitution (Gly-->Ser) at position 9 in the A-chain. A second molecular form of Przewalski's horse insulin isolated in this study was shown to represent the gamma-ethyl ester of the Glu17 residue of the A-chain. This component was probably formed during the extraction of the...
Booth TM, Proudman CJ, Edwards GB.A 6-year-old mare was presented for acute abdominal pain unresponsive to analgesics. Exploratory laparotomy revealed entrapment of the small colon through a 12 cm rent in the mesocolon. The incarcerated small colon was manually reduced and the rent in the mesocolon was sutured closed. The mare made excellent postoperative recovery and was discharged from the hospital 4 days later. The cause of the rent, which was chronic in appearance, is unknown.
Miyakoshi D, Watanabe A, Ikeda H, Mizuguchi Y.An 8-month-old thoroughbred colt presented with sudden onset right forelimb lameness. A radiographic series of the right carpus was performed, and it revealed a slab fracture of the fourth carpal bone and fracture of the proximal part of the third metacarpal bone. Arthroscopically guided repair of the slab fracture of the fourth carpal bone with a 3.5 mm cortex screw and lag screw fixation of the fracture of the proximal part of the third metacarpal bone were performed. The horse started to race at 32 months old and started in 65 races over three years without any trouble associated with the r...
Kawaguchi K, Church S.This research describes three cases of foals, or young horses, that developed septic arthritis caused by an anaerobic bacterium called Clostridium septicum. All foals were successfully treated with joint irrigation […]
Alexander RM.This research presents the hypothesis and findings that short muscle fibers in horses and other large mammals may protect bones and tendons from damaging vibrations during running, negating the previous […]
Mitten LA, Hinchcliff KW, Sams R.Evaluation of a portable blood gas analyzer, (StatPal II, Unifet, Inc, La Jolla, CA) was performed using tonometered solutions and equine blood. Samples were analyzed by the StatPal II and either an Instrument Laboratory IL1306 (Lexington, MA) or a Radiometer ABL50 blood gas analyzer (Radiometer America Inc., Westlake, OH). Comparison of the StatPal II and the IL1306 was done by analysis of 3 tonometered solutions (acidic, normal, and alkalotic) and 27 equine venous blood samples. Blood pH, PCO2, PO2, and [HCO3] values were altered by IV infusion of 5% sodium bicarbonate or exercising the hors...
Erickson HH, Sexton WL, Erickson BK, Coffman JR.The recognition of the horse as a natural athlete has led to increased interest in equine sports medicine, exercise physiology, new training methods, and factors improving the performance of horses (Engelhardt, 1977; Milne et al., 1977; Bayly et al., 1983b; Persson et al., 1983). A considerable amount of research has been performed in recent years in order to describe the physiological responses of the horse to exercise and training (for reviews see Engelhardt, 1977; Physick-Sheard, 1985; Rose, 1985). Most of these studies, however, have examined the effects of acute exercise training rather t...
Krogh HV, Lundegaard HC.A case of guttural pouch mycosis in an 11-year-old horse is described. The fungus isolated was identified as Emericella nidulans. Housing under bad hygienic conditions without ventilation for three years might have been a predisposing factor.
Borst GH, Smidt WJ, Berghuis GA.The concentrations of progesterone in milk were determined in twenty-one mares to establish a diagnosis of pregnancy in an early stage (15-19 days). Progesterone levels varied from 0.0 to 4.2 ng/ml in nine non-pregnant mares and from 6.7 to 30.0 ng/ml in twelve pregnant mares. Progesterone levels were determined by an enzyme-linked immunosorbent assay (ELISA).
Auer JA, Burch GE, Hall P.The relevant literature on electrostimulation in general, and pulsing electromagnetic fields in particular, is reviewed. DC current influences cell behaviour by affecting transmembrane ion transport, which is often under enzymatic control. Pulsing electromagnetic fields influence cell functions through adsorption of ions or dipole formation at the cell membrane. Invasive and non-invasive DC current stimulation is compared to pulsing electromagnetic fields. The mode of application of pulsing electromagnetic fields to the equine limb and suggested treatment times are briefly discussed. Two case ...
Goulden BE, Barnes GR, Quinlan TJ.This research presents a unique case of laryngospasm in a horse, a condition that is often observed in cats and other domestic animals, but rarely reported in horses. Traditional methodologies […]
Chiwitt CLH, Scurrell EJ, Featherstone HJ, Heinrich CL.A 15-year-old Cob mare presented with a 4-month history of chronic epiphora and intermittent blepharospasm in the right eye. On ophthalmic examination, two translucent aberrant hairs were identified at the third eyelid margin corresponding to an area of corneal fibrosis and neovascularization. Partial excision of the third eyelid was performed, and histopathology confirmed ectopic hair follicles. Two weeks later, clinical signs recurred in the same eye. Examination revealed another pair of aberrant hairs on the bulbar surface of the third eyelid near its leading edge. This portion of the third...
Espinoza-Duarte MR, Ortega-Ochoa C, Baca-Ramirez A, Possani LD, Espino-Solis GP.Horses have played a prominent role in shaping our modern world, with important effects on health. Unfortunately, better characterization of the horse immune system is still needed. In this report, using flow cytometry techniques, four monoclonal antibodies against horse CD11c integrin were characterized and described for their ability to provide a positive recognition signal in peripheral blood mononuclear cells. Further immune cell phenotype experiments were performed using MHC-II, CD14, TLR4 and the specific anti-horse CD11c monoclonal antibody (1C4). With this staining panel, it was possib...
Bewley TA, Li CH.Equine pituitary somatotropin (growth hormone) has been studied by zero-order and second-order absorption spectroscopy, and by circular dichroism. Difference absorption spectra have also been generated during proteolytic digestion of the hormone. The molar extinction coefficient of the native protein was found to be 16,050 +/- 330 M-1 cm-1 at 278.1 nm. Comparison of the conformations of equine somatotropin and somatotropins isolated from several other mammalian species indicates a close structural relationship between these molecules. With the increasing number of species which have been studi...
Geelen SN, Sloet van Oldruitenborgh-Oosterbaan MM, Beynen AC.The hypothesis tested was that the feeding of extra fat to horses would raise the production of plasma triacylglycerols (TAG). To measure TAG secretion, the indirect Triton method was used. Six adult horses were given a low-fat control or a high-fat diet according to a crossover design. In keeping with our earlier work, the high-fat diet lowered fasting plasma TAG concentrations by an average of 42% and raised post-heparin total lipoprotein lipase activity by 79%. The rate of increase in plasma TAG concentration after Triton administration was 49% lower when the horses were fed the high-fat di...
Lindroth KM, Dicksved J, Vervuert I, Müller CE.Free faecal liquid (FFL) is a condition in horses characterised by two-phase (one solid and one liquid) separation of faeces. Causes of the condition are unknown, but disturbed hindgut fermentation has been suggested as it may alter biochemical composition and appearance of faeces in equines. However, information on faecal composition in horses with FFL is scarce. Faecal chemical composition (dry matter, osmolality, ash, macro minerals, short-chain fatty acids (SCFA) and pH) and physical characteristics (free liquid, sand, water holding capacity and particle size distribution) were compared in...
