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.
Rush BR, Raub ES, Rhoads WS, Flaminio MJ, Matson CJ, Hakala JE, Gillespie JR.To determine changes in clinical signs of disease and response to pulmonary function testing in horses with recurrent airway obstruction (heaves) after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively. Methods: 6 horses with inducible and reversible heaves. Methods: Episodes of heaves were induced by exposure (challenge) to moldy hay and straw for 7 days. Horses were assigned to treatment groups (aerosolized beclomethasone dipropionate, parenterally administered dexamethasone, aerosolized propellant [control]), and respiratory frequency and s...
Rush BR, Flaminio MJ, Matson CJ, Hakala JE, Shuman W.To determine cytologic changes in horses with recurrent airway obstruction (heaves) after administration of aerosolized beclomethasone dipropionate and dexamethasone parenterally. Methods: 6 horses with inducible and reversible heaves. Methods: Episodes of heaves were induced by exposure to moldy hay and straw for 7 days. Horses were assigned to treatment groups (aerosolized beclomethasone, parenterally administered dexamethasone, aerosolized propellant), and pulmonary inflammation was evaluated by serial cytologic examination of bronchoalveolar lavage (BAL) fluid samples obtained on days 0, 7...
Audigié F, Pourcelot P, Degueurce C, Denoix JM, Geiger D, Bortolussi C.To evaluate asymmetry in placement of bilateral skin markers on horses and to determine effect of asymmetric skin marker placement on kinematic variables for trotting horses. Methods: 10 horses for evaluation of asymmetry in marker placement; 1 horse for evaluation of effects on kinematic variables. Methods: Asymmetry in marker placement was assessed by attaching markers to horses and comparing radiographs of left and right limbs. An experimental model was developed to determine effects on kinematic variables; accuracy of the model was validated experimentally. Using kinematic data from a clin...
Russell KE, Walker KM, Miller RT, Sellon DC.To determine blood protein concentration, immunoglobulin concentration, and lymphocyte profiles in equine infectious anemia virus (EIAV) seropositive, naturally infected horses without clinical signs of disease. Methods: 26 clinically normal seropositive horses, 6 febrile ponies with experimentally induced EIA, and 52 clinically normal seronegative horses and ponies. Methods: Serum and EDTA-anticoagulated blood were obtained from all horses and ponies, and total serum protein and albumin concentrations, immunoglobulin concentrations, and blood lymphocyte subset counts were determined. Results:...
Borchers K, Wolfinger U, Ludwig H, Thein P, Baxi S, Field HJ, Slater JD.Two 18-month-old naturally reared ponies were used to investigate the pathogenicity of EHV-2. After dexamethasone treatment, pony 1 was inoculated intranasally with EHV-2 strain T16, which has been isolated from a foal with keratoconjunctivitis superficialis and pony 2 was similarly inoculated with strain LK4 which was originally isolated from a horse with upper respiratory tract disease. Following virus inoculation, pyrexia was not detected in either pony but both developed conjunctivitis, lymphadenopathy, and coughing. EHV-2 was detected in nasal mucus samples up to day 12 post infection (p....
Fedde MR, Erickson HH.Blood was taken from 49 Thoroughbred horses before and after racing at the track to determine if frusemide modified the apparent viscosity of the blood and to determine the effects of changes in shear rate and packed cell volume (PCV), associated with strenuous exercise, on apparent and relative viscosities. Small increases in apparent viscosity of the blood (at a specified PCV and shear rate) occurred in horses given frusemide compared to those receiving no frusemide; however, no differences were seen in relative viscosity. Although 2 groups of horses, those receiving frusemide before racing ...
Young LE, Blissitt KJ, Clutton RE, Molony V.To describe the haemodynamic effects of a 60 min infusion of dopamine 4 microg/kg bwt/min during halothane anaesthesia, 7 mature Thoroughbred horses were studied. The infusion began 1 h after induction of anaesthesia by romifidine (100 microg/kg) and ketamine (2.2 mg/kg bwt). Throughout the period of dopamine infusion and for 30 min after its discontinuation, the horses were ventilated by intermittent positive pressure to maintain PaCO2 between 4.6-5.4 KPa. Inspired halothane concentration was adjusted to maintain an end tidal halothane concentration of 0.9%. Haemodynamic variables were measur...
Doherty TJ, Andrews FM, Provenza MK, Frazier DL.Gastric emptying was evaluated in ponies using the acetaminophen (AP) method. Fifteen minutes after i.v. administration of metoclopramide, erythromycin, yohimbine, atropine or saline, the ponies were given AP by stomach tube. Blood samples for AP analysis were collected at baseline and 15, 30, 45, 60, 75, 90, 105 and 120 min after AP administration. Time to reach peak serum concentration (Tmax), maximum serum concentration (Cmax) and area under the AP serum concentration vs. time curve (AUC) were determined for each treatment group. In the control group, Tmax was 31 min and this decreased sign...
Doherty TJ, Frazier DL.This study investigated the effect of lidocaine i.v. on halothane minimum alveolar concentration (MAC) in ponies. Six ponies were anaesthetised with thiopentone and succinylcholine, intubated and anaesthesia maintained with halothane. Ventilation was controlled and blood pressure maintained within clinically acceptable limits. Following a 2 h equilibration period, baseline halothane MAC was determined. The ponies were then given a loading dose of lidocaine (2.5 or 5 mg/kg bwt) or saline over 5 min, followed by a constant infusion of lidocaine (50 or 100 microg/kg/min, or saline, respectively)....
Harkins JD, Mundy GD, Stanley S, Woods WE, Sams RA, Richardson DR, Grambow SC, Tobin T.Isoxsuprine is reported to be a peripheral vasodilator used in human and veterinary medicine to treat ischaemic vascular disease. In horses, it is generally administered orally to treat navicular disease and other lower limb problems. To define the scope and duration of its pharmacological responses after oral administration, 6 horses were dosed with isoxsuprine HCl (1.2 mg/kg bwt) q. 12 h for 8 days and then tested to assess the duration and extent of pharmacological actions. There was no significant difference between isoxsuprine and control treatment values for heart rate, spontaneous activ...
Holdstock NB, Ousey JC, Rossdale PD.The aim of this study was to determine glomerular filtration rate (GFR), effective renal plasma flow (RPF) and filtration fraction (FF) values in Pony foals during the first 10 days post partum in order to assess any age-related changes and the reliability of the single injection inulin/p-aminohippurate (PAH) method. Arterial blood pressure and pulse rate were determined in Pony and Thoroughbred (TB) foals during the first 10 days post partum to establish age-related changes, differences between breeds and possible interrelationships with GFR and RPF. Inulin and PAH were injected intravenously...
Taylor PM, Kirby JJ, Shrimpton DJ, Johnson CB.Sixteen colts were premedicated with acepromazine and anaesthesia was induced with detomidine and ketamine. Ponies were randomly allocated to receive halothane (HAL) or infusion of detomidine, ketamine and guaiphenesin (DKG) to maintain anaesthesia. Heart and respiratory rate, ECG, mean arterial blood pressure (MABP), cardiac index (CI), blood gases and plasma cortisol, ketamine and guaiphenesin were measured. Surgical castration took place between 45 and 75 min and anaesthesia lasted 90 min. MABP with DKG was significantly higher than with HAL, and, with HAL, MABP increased from pre-surgery (...
Meyer TS, Fedde MR, Gaughan EM, Langsetmo I, Erickson HH.Exercise-induced pulmonary haemorrhage (EIPH) causes serious economic losses in the horse racing industry. Endoscopic examination indicates that 40-90% of horses exhibit EIPH following sprint exercise, but the limitations of the endoscope prevent diagnosis in many horses. Bronchoalveolar lavage (BAL) was utilised to detect red blood cells (RBCs) in the terminal airways in 6 horses. Two lavages were performed at weekly intervals prior to exercise, one within 90 min after exercise, and 5 at weekly intervals after exercise. The horses were exercised strenuously at 12.5-14.6 m/s on a treadmill (3 ...
Valk N, Doherty TJ, Blackford JT, Abraha TW, Frazier DL.The effect of cisapride pretreatment on gastric emptying in horses was determined by measuring serum concentrations of acetaminophen, a drug known to be readily absorbed in the small intestine but not in the stomach. The time to reach maximum serum acetaminophen concentrations (Tmax), the maximum serum concentrations (Cmax) and the area under the serum acetaminophen concentration vs. time curves (AUC) were compared among treatment groups. In the first part of the study, the effect of orally administered cisapride (0.1, 0.2 and 0.4 mg/kg bwt) on gastric emptying was examined in 6 normal fasted ...
Rand T, Bindeus T, Alton K, Voegele T, Kukla C, Stanek C, Imhof H.The authors evaluate the role of low-field strength magnetic resonance imaging (MRI) compared with sonography in the evaluation of degenerative changes of tendons, with histologic correlation, based on investigations of horse cadavers. Methods: Low-field MRI and sonography was performed in 42 hours specimens for the evaluation of tendons and ligaments. Magnetic resonance imaging included sagittal and axial T1-weighted, T2-weighted, and gradient echo images. Sonography and MR images were evaluated for degenerative changes or tears and the findings were correlated with the histologic results. Re...
Lendal S, Larsen MM, Bjørn H, Craven J, Chriél M, Olsen SN.A questionnaire survey to obtain information on endoparasite control practices and management on 68 Danish horse farms was undertaken in 1995. The study revealed that foals, young horses and adults were on average, annually treated 4.3, 4.0 and 3.7 times, respectively. The most commonly used drug from 1993-1995 was ivermectin. On average 2.4 different drugs were used annually. The most used method of weight estimation was eye measure: for foals by 78%, for youngsters by 81% and adults by 82% of the herd owners. The most commonly used weight in the dosing of anthelmintics was individual weights...
van den Berg JS, Guthrie AJ, Meintjes RA, Nurton JP, Adamson DA, Travers CW, Lund RJ, Mostert HJ.The objectives of this trial were to measure the water and electrolyte intake and loss, of horses during road transportation in relatively hot environmental conditions. Six mature, Thoroughbred horses in full training were used in a balanced crossover design. The horses were conditioned on a treadmill for 6 weeks before the start of the trial in order to simulate the type of horse that is transported most often over long distances in South Africa. The horses were assigned randomly to one of 2 treatment groups. On a particular day 3 horses were transported, while the other horses served as cont...
Raisis AL, Hodgson JL, Hodgson DR.Twenty-one compromised neonatal foals hospitalised at the Rural Veterinary Centre (RVC) during 1993 were studied to determine i) serum gentamicin concentrations obtained when gentamicin was administered at 3.3 mg/kg bwt twice daily i.m.; ii) factors which contributed to inter-foal variation in serum gentamicin concentrations achieved and iii) clinical efficacy of gentamicin therapy in foals with confirmed septicaemia. Septicaemia was confirmed in 7 foals with positive blood cultures and suspected in 8 foals with a sepsis score > 11. Peak serum concentrations (Ps) were > 6 microg/ml in al...
Craven J, Bjørn H, Henriksen SA, Nansen P, Larsen M, Lendal S.This study reports on the prevalence of anthelmintic resistance in strongyles of horses in Denmark. Of 5 methods used for the calculation of faecal egg count reduction (FECR) the method recommended by the World Association for the Advancement of Veterinary Parasitology, for the detection of resistance in sheep was the most sensitive procedure for detecting resistance. Using this method benzimidazole resistance was detected on 33 of 42 farms (79%) examined. Pyrantel was tested on 15 farms and FECR tests indicate resistance on 3 (30%) farms. On 2 farms on which resistance to pyrantel was detecte...
Gerard MP, Healy LN, Bowman KF, Miller RT.Two months after colic surgery, subcutaneous masses were found on the ventral and lateral portions of the thorax of a 3-year-old Hanoverian-cross filly. Six months later, the filly was admitted for evaluation of severe lameness. Arthrocentesis of the tarsocrural joint yielded clotted sanguineous material; however, unusual multinucleated giant cells were seen. Radiography of the right tarsus revealed soft tissue opacity and degenerative joint disease. The filly was euthanatized to prevent further suffering. At necropsy, multiple soft-tissue masses were located throughout the fascial planes of t...
Mumford EL, Traub-Dargatz JL, Salman MD, Collins JK, Getzy DM, Carman J.To develop a system to monitor and detect acute infections of the upper respiratory tract (i.e., nares, nasopharynx, and pharynx) in horses and to assess the association among specific viral infections, risk factors, and clinical signs of disease. Methods: Prospective study. Methods: 151 horses with clinical signs of acute infectious upper respiratory tract disease (IURD) from 56 premises in Colorado. Methods: Health management data, blood samples, and nasal or nasopharyngeal swab samples were obtained for 151 horses with clinical signs of acute IURD. Of these horses, 112 had an additional blo...
Wiemer P.In 22 stallions the surgically prepared spermatic cord was crushed and ligated. Preoperative and postoperative plasma-testosterone concentrations were measured and 60 days after surgery a HCG-stimulation test was carried out in 12 horses. In these 12 horses the testosterone production had ceased. In all 22 horses the wounds healed by primary intention. Ligation of the spermatic cord is a castration technique without surgical complications, at least in this study.
Ninu AR, Saxena AC, Sivanarayanan TB, Remya V, Binsila BK, Maiti SK, Zama MM.A nulliparous non-descript mare was presented with a complaint of dystocia. The mare was recumbent and physical examination revealed that the animal was in shock. There was no straining and foetal forelimbs were visible outside the vulva. The foetus was dead as there was no pedal reflex. Vaginal examination revealed anterior presentation with dorso-sacral position and rigid lateral head deviation. Pre-operatively, the mare was given 5 ml Tetanus toxoid and 3 g Ceftriaxone as intramuscular injection, and 5 ml Dexamethasone in 15 L of 5% Dextrose Normal Saline (DNS) as intravenous (i/v) infusion...
Mair TS, Sherlock CE, Fews D, Harley R, Pearson GR.Histological evidence of fibrosis affecting the outer layer of the large intestinal tunica muscularis was identified in five of 32 horses affected by colic. In three cases, foci of pale eosinophilia and vacuolation of myocytes were observed. These findings are suggestive of a degenerative and fibrotic abnormality in the outer layer of the tunica muscularis of the large intestinal smooth muscle of some horses with colic.
Wotman KL, Utter ME.To assess the effect of treatment with a topical ophthalmic preparation of 1.2% nalbuphine solution on corneal sensitivity in clinically normal horses. Methods: 8 horses. Methods: Baseline corneal touch threshold (CTT) was measured (defined as the mean filament length [mm] at which a consistent blink response was elicited) for both eyes of each horse by use of a Cochet-Bonnet aesthesiometer. Subsequently, 0.2 mL of 1.2% nalbuphine solution was instilled in 1 randomly selected eye of each horse, and 0.2 mL of artificial tears solution was instilled in the contralateral eye (control treatment). ...
Dolvik NI, Gaustad G.The degree of lameness of 265 randomly selected three-year-old standardbred trotters was assessed on a fixed point scale with 0 indicating soundness and 5 indicating that the animals were not weightbearing. Two variables were used to describe the signs of lameness; one was the continuous variable: the sum of the initial lameness score and the lameness scores after separate flexion tests of the carpal, stifle/tarsal and phalangeal joints and the second was the bivariate variable; the ratio of lame/sound horses. The mean (sd) heritability of the continuous variable was estimated to be 0.25 (0.21...
Ellero N, Lanci A, Avallone G, Mariella J, Castagnetti C, Muscatello LV, Di Maio C, Freccero F.Seizures, coma and death rapidly appeared after admission in a one ‑month‑old foal with a history of lethargy, fever and anorexia. Severe icterus and necrotizing hepatitis were observed at necropsy. Clinical signs, laboratory and postmortem findings were compatible with a suspect of clostridial hepatitis. Tyzzer’s disease was confirmed by the presence of organisms morphologically consistent with Clostridium piliforme in the hepatocytes at the margins of multiple areas of hepatic necrosis. To the authors’ knowledge, this is the first reported case of clostridial hepatitis caused by Clos...
Rantanen NW.The ability to image the liver in horses can add valuable diagnostic information or aid in guided biopsy procedures. Anytime the size, shape, position, and texture of the liver can be determined, additional information about the horse's condition is gained. Conditions such as cholelithiasis, neoplasia, fibrosis can be detected ultrasonographically.
Jaworska J, de Mestre AM, Wiśniewska J, Wagner B, Nowicki A, Kowalczyk-Zięba I, Wocławek-Potocka I.Endometrial immune cells are essential to support uterine functions across the estrous cycle and in preparation for pregnancy. It has been acknowledged that changes in phenotype and/or numbers of lymphocytes, such as regulatory T cells (Tregs) and NK cells, might result in lower fertility in women and mice. Little is known about equine endometrial immune cells across the estrous cycle. Here, we compared the populations of endometrial Tregs and NK cells in estrus and diestrus in mares. Endometrial biopsy and blood samples were taken in estrus and diestrus from 11 mares ages 4-12 years. Flow cyt...
Ichinose T, Miller MG, Shibamoto T.Free malonaldehyde formed in the microsomes prepared from livers of monkey, rat, rabbit, mouse, cow, pig, dog, sheep and horse upon CCl4 oxidation was derivatized by reaction with N-methylhydrazine to form 1-methylpyrazole which was subsequently analyzed by capillary gas chromatography. Among the livers from animals tested, the monkey and rat livers produced the most malonaldehyde upon CCl4 treatment. Horse liver showed the greatest resistance to CCl4 oxidation. The gas chromatography method used in the present study exhibited an accurate and specific measurement of free malonaldehyde that mig...
Bigot G, Bouzidi A, Rumelhart C, Martin-Rosset W.Two specimens (70.0 x 4.5 x 1.8 mm) (proximal and distal) of cortical bone were taken from each of the cranial, caudal, lateral and medial quadrants at mid-diaphysis of the third metacarpus and metatarsus of French saddle horses (12 males and seven females) aged from 1 day to 4 years. The mechanical properties (bending strength, Young's modulus, yield stress and ultimate specific deflection) were determined by a 4-point bending test, loading at a rate of 166 x 10(-6) ms-1. During growth, the mechanical properties of the cortical bone were not significantly different (p > 0.05) between metacarp...
Mok CH, MacLeod JN.Within developing synovial joints, interzone and anlagen cells progress through divergent chondrogenic pathways to generate stable articular cartilage and transient hypertrophic anlagen cartilage, respectively. Understanding the comparative cell biology between interzone and anlagen cells may provide novel insights into emergent cell-based therapies to support articular cartilage regeneration. The aim of this study was to assess the kinetics of gene expression profiles in these skeletal cell lines after inducing chondrogenesis in culture. Interzone and anlagen cells from seven equine fetuses w...
Williams RJ, Marlin DJ, Smith N, Harris RC, Haresign W, Davies Morel MC.To determine the effects of exercise, high heat and humidity and acclimation on plasma adrenaline, noradrenaline, beta-endorphin and cortisol concentrations, five horses performed a competition exercise test (CET; designed to simulate the speed and endurance test of a three-day event) in cool dry (CD) (20 degrees C/40% RH) and hot humid (30 degrees C/80% RH) conditions before (pre-acclimation) and after (post-acclimation) a 15 day period of humid heat acclimation. Plasma adrenaline and noradrenaline concentrations pre-acclimation were significantly increased compared with exercise in the CD tr...
Dawson FL, Durrant DS.Seventy-three samples of serum, from 69 horses and one zebra, were subjected to the Rose Bengal Plate, serum tube agglutination, complement fixation, and anti-equine globulin (Coombs') tests for brucellosis. Fifty-one of the samples, from 48 horses, were submitted by practising veterinary surgeons; of these, 22 samples were associated with clinical conditions which might have been due to brucellosis. Fourteen samples were from healthy horses known to have been in contact with infected cattle, and six were from horses which were known not to have been exposed to brucellosis. More reactions at a...
Swadzba ME, Hauck SM, Naim HY, Amann B, Deeg CA.Complete knowledge of autoantigen spectra is crucial for understanding pathomechanisms of autoimmune diseases like equine recurrent uveitis (ERU), a spontaneous model for human autoimmune uveitis. While several ERU autoantigens were identified previously, no membrane protein was found so far. As there is a great overlap between glycoproteins and membrane proteins, the aim of this study was to test whether pre-enrichment of retinal glycoproteins by ConA affinity is an effective tool to detect autoantigen candidates among membrane proteins. In 1D Western blots, the glycoprotein preparation allow...
Palmer SE, McGill LD.Freshly harvested equine skin incised with an electrosurgical unit, a radiosurgical device, or a carbon dioxide (CO2) laser was examined by light microscopy to determine the extent of thermal injury caused by each instrument. There was no significant difference between the thermal injury caused by the electrosurgical unit in the pure-cut mode and the CO2 laser in the superpulse mode, or between the electrosurgical unit and the radiosurgical device in the fully filtered cut mode. However, thermal injury caused by the CO2 laser was significantly less than that caused by the radiosurgical device....
Brianceau P, Divers TJ.A hypercoagulable condition and poor perfusion to distal extremities might occur during equine endotoxaemic or septic shock, which could cause thrombosis of limb arteries. In our review, thrombosis occurred in neonatal foals in association with gram-negative bacteraemia. In 3 older foals and adults, thrombosis was associated with inflammatory bowel disease, diarrhoea and toxaemia. All patients had been treated with broad-spectrum antibiotics, nonsteroidal antiinflammatory drugs and i.v. crystalloid solutions. Two horses received i.v. hyperimmune plasma. A generalised coagulopathy was not suspe...
Blanch EW, Morozova-Roche LA, Hecht L, Noppe W, Barron LD.Vibrational Raman optical activity (ROA) spectra of the calcium-binding lysozyme from equine milk in native and nonnative states are measured and compared with those of the homologous proteins hen egg white lysozyme and bovine alpha-lactalbumin. The ROA spectrum of holo equine lysozyme at pH 4.6 and 22 degrees C closely resembles that of hen lysozyme in regions sensitive to backbone and side chain conformations, indicating similarity of the overall secondary and tertiary structures. However, the intensity of a strong positive ROA band at approximately 1340 cm(-1), which is assigned to a hydrat...
Lilly ML, Gonçalves Arruda A, Proudfoot KL, Herron ME.To survey first-year veterinary students' knowledge of companion animal (dog, cat, and horse) behavior and popular-culture (ie, pop-culture) behavior myths related to animal body language, motivations, and learning prior to participation in an introductory animal behavior course; evaluate potential associations between sources of prior behavior knowledge and knowledge on the preclass survey; and determine whether postclass scores on the same survey were predictive of final examination score for the behavior class. Methods: 156 first-year veterinary students. Methods: Students were invited to p...
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...
Cuervo-Arango J, Domingo-Ortiz R.Prostaglandins play an obligatory role during the process of ovulation in mammals. Ovulation can be blocked by intrafollicular administration of non-steroidal anti-inflammatory drugs (NSAIDs) in several domestic species including the mare as well as by systemic administration of these drugs in women. In the mare, the effect of systemic NSAIDs treatment on ovulation has not been critically studied. The objectives of this study were: a) to determine whether high dose of flunixin-meglumine (FM) administered systemically to mares during the periovulatory period was able to block ovulation; and b) ...
Ott EA, Asquith RL.Thirty-three Thoroughbred and Quarter Horse yearlings were used in two experiments (18 in Exp. 1 and 15 in Exp. 2) to determine the influence of trace mineral (TM) supplementation on growth and bone mineral content in young growing horses from 340 to 452 d of age. In each experiment the yearlings were assigned at random within breed and sex outcome groups to one of three treatments. Horses were fed assigned concentrates individually to appetite for two 1.5-h feeding periods, daily and group-fed Coastal bermudagrass (Cynodon dactylon) hay in drylot paddocks at a rate of 1.0 kg/100 kg BW daily. ...
