Veterinary medicine for horses encompasses the study and application of medical practices to diagnose, treat, and prevent diseases in equine species. This field involves a comprehensive understanding of equine anatomy, physiology, pathology, and pharmacology. Veterinary practitioners employ a range of diagnostic tools and therapeutic interventions to address health issues in horses, including lameness, gastrointestinal disorders, respiratory conditions, and infectious diseases. Preventative care, such as vaccination and deworming programs, is also a significant aspect of equine veterinary medicine. This page gathers peer-reviewed research studies and scholarly articles that explore various aspects of veterinary medicine as it pertains to horses, including advancements in diagnostic techniques, treatment protocols, and preventive health strategies.
Baker B, Gaffin SL, Wells M, Wessels BC, Brock-Utne JG.Endotoxins (lipopolysaccharides-LPS) and anti-endotoxin IgG antibodies were measured in racehorses before and after races of 1,000, 2,000 and 2,800 m. Results show that the mean plasma concentration of endotoxin increased significantly (p less than 0.02) while the anti-LPS IgG concentration decreased significantly (p less than 0.005) in all horses following the races. Pre-race and post-race anti-LPS IgG levels in racing-fit racehorses were significantly higher than in untrained horses (p less than 0.05). The possibility therefore exists that training-induced stress leads to leakage of LPS into...
Snyder JR, Olander HJ, Pascoe JR, Holland M, Kurpershoek CJ.Morphologic changes that develop sequentially in the large colon during experimentally induced ischemia were documented in 14 halothane-anesthetized horses. Colonic ischemia was induced by 4 types of vascular occlusion, 24 cm proximal and distal to the pelvic flexure. The effect of transmural (colonic wall) vascular compression combined with either venous occlusion (3 horses, group A) or venous and arterial occlusion (3 horses, group B) of the colonic vessels was studied for 1, 2, and 6 hours of occlusion. Also observed was the effect of reperfusion for 0.5 hour after release of the clamps for...
Dodman NH, Shuster L, Court MH, Patel J.Nalmefene, an opioid antagonist, caused a decrease in self-mutilative behavior in a 500-kg stallion. Self-mutilative attempts were counted during a control period and on 4 subsequent occasions after the IM administration of 100 mg, 200 mg, 400 mg, or 800 mg of nalmefene. The frequency of self-mutilation decreased with increasing doses of nalmefene and was virtually abolished with the 800-mg dose.
Kotzé SH.The muscle layers of the ileocaecal junctions of horses (n = 18), plains zebras (Equus burchelli antiquorum) (n = 3), mountain zebras (Equus zebra zebra) (n = 2), and a donkey were examined macroscopically and microscopically. The muscular tunic of the ileocaecal papilla was made up of 3 layers: an innermost circular layer which was a continuation of the circular muscle of the ileum, a central longitudinal layer which was a continuation of one part of the longitudinal layer of the ileum and an outermost layer, composed of two collateral semicircular lips, formed by the circular layer of the ca...
Lavoie JP, Harnagel SH.A small tear in the urinary bladder of a severely debilitated 4-day-old foal was managed with an indwelling urinary catheter connected to a urine collecting system. Fluid therapy, parenteral nutrition, and antimicrobial agents were used during the initial management of the ruptured bladder. Aseptic technique for catheter care and systemic administration of antimicrobial agents prevented the development of bacterial cystitis. Catheter management required constant monitoring, but the bladder defect was sealed within 5 days. Fungal arthritis caused by Candida tropicalis, immune-mediated anemia, d...
Madison JB, Scarratt WK.The deposition of immune complexes in the synovial membrane resulted in polysynovitis in 4 foals. All 4 foals had an infection at a site other than the joints. The polysynovitis was characterized by marked effusions of affected joints and joint stiffness. Bacterial and mycoplasmal cultures of the joints did not yield growth. Staining of synovial membrane biopsy specimens with fluorescein-labeled anti-equine IgG revealed immune complexes in the synovial membrane. Immune-mediated polysynovitis might develop in foals with bacterial infections. We propose that deposition of immunoglobulin in the s...
Freeman DE, Cimprich RE, Richardson DW, Gentile DG, Orsini JA, Tulleners EP, Fetrow JP.Strangulation obstruction was induced in anesthetized ponies for periods of 2 and 3 hours by clamping 45-cm segments of jejunum and their veins only (venous strangulation obstruction, VSO) and arteries and veins (arterial and venous strangulation obstruction, AVSO). These types of strangulation obstruction were studied in 4 segments in each of 4 ponies allowed to survive 12 hours (group 1) and in a single segment in each of 10 ponies allowed to survive 42 days (group 2) after the strangulation period ended. On visual inspection, segments subjected to VSO had hemorrhage and edema in the bowel w...
Freeman DE, Gentile DG, Richardson DW, Fetrow JP, Tulleners EP, Orsini JA, Cimprich R.Strangulation obstruction was induced in anesthetized ponies for periods of 2 and 3 hours by clamping 45-cm segments of jejunum and associated veins (venous strangulation obstruction) and arteries and veins (arterial and venous strangulation obstruction). Four segments were studied in each of 7 ponies allowed to survive 12 hours, 2 segments in a pony that was allowed to survive 1 hour, and 1 segment in each of 10 ponies allowed to survive 42 days after the strangulation periods ended. Fifteen minutes after the periods of strangulation obstruction ended, the viability of test segments was asses...
Rogers AL.In early December 1986 A-equi-2 influenza virus was isolated for the first time in the Republic of South Africa. All horses were susceptible to the highly contagious aerosol-borne orthomyxovirus resulting in widespread outbreaks of equine influenza with typical primary respiratory symptoms. Treatment consisted of rest, anti-inflammatory drugs, antibiotics and good nursing. Future protection can be obtained by vaccination.
Qureshi GA, Eriksson A.A method for the routine determination of the beta-adrenergic drugs clenbuterol and mabuterol in equine plasma has been developed. The drugs were isolated from alkalinized plasma by liquid-liquid extraction. The organic phase was evaporated to dryness and the residue was dissolved in the mobile phase prior to injection. The recoveries were 98% and 95% for clenbuterol and mabuterol, respectively. The drugs were separated by reversed-phase high-performance liquid chromatography and quantitated by a use of a coulometric detector set at +0.75 V vs. the internal reference electrode. The influence o...
Ramey DW.An 8-year-old Thoroughbred gelding was determined to have a sagittal fracture of the central tarsal bone. Lag screw fixation of the fracture enabled the horse to return to jumping, although degenerative arthritis of the distal intertarsal joint was apparent radiographically 17 months after the injury.
Schumacher J, Smith BL, Morgan SJ.A 2-year-old Quarter Horse gelding was examined for torticollis, facial protuberances over the frontal and maxillary sinuses, and persistent nasal discharge unresponsive to antibiotics. Radiograph revealed an osseous mass in the right paranasal sinuses. Histologic examination of the biopsied mass led to a diagnosis of osteoma. The mass was removed surgically in sections from the right frontal and maxillary sinuses through separate bone flaps, and sinuses were irrigated with saline solution for 8 days after surgery. Two weeks after surgery, radiography revealed small osseous opacities in the ri...
Johansson M, Anlér EL.A quantitative method for the analysis of flunixin, 2-(2-methyl-3-trifluoromethylanilino) nicotinic acid, in equine urine by gas chromatography with nitrogen-phosphorus detection has been developed. Flunixin and the internal standard, mefenamic acid, N-(2,3-xylyl) anthranilic acid, were analysed after extractive methylation of the carboxylic acid group using methyl iodide. The extraction and alkylation conditions of flunixin and mefenamic acid have been studied. The detection limit of the method was 0.25 mumol/l flunixin in urine (74 ng/ml). Flunixin was found to be conjugated to 96.5% in equi...
Karàdi I, Kostner GM, Gries A, Nimpf J, Romics L, Malle E.Earlier studies demonstrated that lipoprotein (a), a lipoprotein of high atherogenicity, possesses proteolytic activity. In this report, we provide evidence that the lipoprotein (a)-specific antigen, apoprotein (a) is immunochemically related to plasminogen. This was demonstrated by polyclonal antisera from rabbit, sheep and horse, and with three monoclonal antibodies from mouse. Using immunospecific adsorbers against lipoprotein (a), all plasminogen could be adsorbed from lipoprotein (a)-positive and apparently lipoprotein (a)-negative plasma. As an additional similarity to plasminogen, lipop...
Crawley GR, Grant BD, White KK, Barbee DD, Gallina AM, Ratzlaff MH.A modified Cloward's technique was performed for arthrodesis of one metacarpophalangeal (MCP) joint in eight horses. Dorsal arthrotomies were performed medial and lateral to the common digital extensor tendon and two 16 mm holes were drilled through the joint. A perforated cylindrical stainless steel basket filled with cancellous bone was impacted into each hole. The limbs were supported in casts for 8 weeks. The joints were examined and radiographed at 4 weeks, 8 weeks, 6 months, and 10 months. One horse was euthanatized at week 14 to assess the progress of the arthrodesis. In the other seven...
Grünig G, Hermann M, Winder C, Von Fellenberg R.Cell-free supernatants (sol phases), obtained after centrifugation (50,000 x g for 45 minutes) of respiratory tract secretions from horses with chronic pulmonary disease, were assayed for procoagulant activity (PCA) in a one-stage clotting assay. Of the 103 specimens tested, 59% (61) contained PCA. Procoagulant activity was detected most often in respiratory tract secretions of severely affected horses and was correlated with the quantity of neutrophils in the respiratory tract secretions. In 12 of the 17 secretions tested, the clotting time was decreased in a dose-dependent manner. However, i...
Cook RF, Sinclair R, Mumford JA.An antigen capture indirect enzyme linked immunosorbent assay (ELISA) was developed to detect influenza nucleoprotein antigen in nasal secretions from horses infected with A/equine/H3N8 viruses. Results from this assay were compared with conventional virus isolation in embryonated hens eggs.
Labadia A, Rivera L, Costa G, Garcia-Sacristan A.alpha and beta-adrenergic receptors in detrusor muscle and bladder base of horses were investigated by in vitro responses of smooth muscle strips to exogenous agonist and antagonist drugs. Noradrenaline, isoprenaline and salbutamol induced relaxation of detrusor muscle strips which was significantly inhibited by propranolol and butoxamine suggesting that the response is mediated by beta-2 adrenergic receptors. In the urinary bladder base noradrenaline, phenylephrine and B-HT 920 induced strong contractile effects. These contractile responses were inhibited by the alpha antagonist phenoxybenzam...
Merkens HW, Schamhardt HC.The distribution of the ground reaction forces (GRF) over the concurrently loaded limbs of the normally walking horse was determined from 'representative' GRF patterns of all limbs, which were plotted in correct time order after analysis of simultaneously taken high-speed film. This procedure visualises the GRF patterns of each of the four limbs in relation to the GRF pattern(s) of the one or two concurrently loaded limb(s) during a complete stride. In 15 clinically sound horses the mean averaged GRF data and temporal stride parameters showed an almost complete symmetry between both the foreli...
Bertone JJ.Six standing awake adult horses were instrumented for measurement of mean arterial, central venous, and pulmonary arterial blood pressures (mm of Hg), thermodilution cardiac output (ml/kg/min), and pulmonary arterial blood temperature (C). Total peripheral resistance was calculated from these values. Base-line data were accumulated, and a single dose of hydralazine HCl (0.5 mg/kg) was administered IV. Horses were monitored for 420 minutes after hydralazine administration. Mean arterial and central venous blood pressures did not change from the base-line values. Cardiac output and heart rate we...
Brooks CL, Garry F, Swartout MS.Analytical characteristics of photometry and ion-specific potentiometry for urine from sheep, horses, cows, dogs, and cats were determined, using solutions of sodium and potassium chloride. The performance of both methods were acceptable, but the ion-specific potentiometer (in the mode for urine analysis) was superior in terms of linearity of response and correlation between actual vs measured concentrations. Coefficients of variation of either method for repeated analyses of various concentrations of sodium and potassium were always less than 2.5%. The measurement of sodium concentration in u...
Somm F, Suárez Sánchez-Andrade J, Martens A, Zedler ST, Klopfenstein MD, Boswell JC, Bladon BM, Lischer CJ, Richardson DW, Auer JA, Fürst AE....To report on technical aspects and outcomes after scapulohumeral arthrodesis (SHA) with a locking compression plate (LCP) in small equids. Methods: Retrospective multicenter case series. Methods: Client-owned Shetland Ponies, Miniature Shetlands, and American Miniature Horses (n = 15). Methods: Inclusion criteria were completed SHA with an LCP to treat scapulohumeral osteoarthritis/subluxation and availability of postoperative radiographs. Contributing surgeons completed a questionnaire to collect data. All radiographs were reviewed for this study. Follow-up information was obtained via re-a...
Ter Woort F, Stefanovski D, Reef VB.Hyperthyroidism is a predisposing factor for atrial fibrillation (AF) in humans. The relationship between high thyroid hormone (TH) and AF in horses has not been evaluated. Objective: The aim of this study is to identify whether (1) high TH concentrations were present in horses with AF, (2) other cardiovascular effects were observed in horses with high TH and AF, and (3) TH status affected recurrence rate. Methods: Twenty-three horses presented with naturally occurring AF. Methods: Prospective case-control clinical study. Thyroid hormone concentration was measured in horses presenting with AF....
Rezai A, Underwood JL, Jalali GR, Mathias S, Allen WR, Mowbray JF.Recurrent spontaneous abortion occurs in 1 in 500 random matings and usually results in abortion of all pregnancies. If absence of antibody to a paternally derived antigen caused abortion, the woman would be expected to make antibody to the other paternal antigen and abort only half her pregnancies. Methods: Microvesicles were prepared from equine placentae. Acid-eluted IgG antibody was eluted from the polymorphic R80K antigen and used to type the residual R80K antigen on vesicles or on peripheral blood leucocytes. Results: In several equine sibships all the half-sibs had the same paternal R80...
Tabar-Rodriguez JJ, Cruz AM, Monteith G, Gordon K, Hurtig MB.OBJECTIVE-To use quantitative ultrasonography to evaluate the association between the speed of sound (SOS) at 9 sites in the third metacarpal bone (MCIII) of racing Thoroughbreds with workload accumulation and the effect that MCIII failure has on this association. ANIMALS-Sixty-two 2- and 3-year-old Thoroughbreds in racing condition. PROCEDURES-Cumulative work index (CWI) was used to calculate total workload (CWI(total)) and also 3 independent CWIs for the various gaits (ie, trot [CWI(trot)], gallop [CWI(gallop)], and race [CWI(race)]) used during training and racing. Speed of sound was monito...
Amin TM, Sirs JA, Allen BV, Colles CM.A preliminary investigation has been undertaken of blood rheology in horses and ponies, its variation in navicular disease and the changes following treatment with warfarin. Erythrocyte flexibility, measured by a centrifuge packing technique, is higher in horses (30 per cent min-1) than in ponies (23.8 per cent min-1). There are corresponding differences in blood viscosity. The high erythrocyte flexibility in horses is caused by an unknown factor present in plasma. The erythrocyte flexibility in horses with navicular disease is even higher, at 38.5 per cent min-1. Treatment with warfarin reduc...
Ek N.Studies of transferrin (Tf) concentration in sera of sick horses were carried out using Mancini’s immunodiffusion technique. Relative values against a chosen reference serum were determined for a total of 112 horses. Horses with acute infections had Tf values significantly below the normal. The lowest individual Tf value in this group (46%) was found in a six-months-old foal with temperature 41°C and watery diarrhoea. Horses suffering from acute laminitis also had decreased Tf values. The lowest value in the whole material (45%) was found in a horse belonging to this group. There was a posi...
Appel G, Briese A, von Holleben K, von Mickwitz G, von Wenzlawowicz M.It is reported on the fatal accident of a horse due to a cross-beam too low above the door of the stable, in which the animal suffered several skull fractures and a tear of the musculus longus capitis from the base of the skull. The aim of this article is, to supply a contribution to the establishment of minimal requirements for the housing of horses, in this case for the request of the minimum height of stable doors and ceilings as well as for constructions on horse transporters. On the grounds of this example, the natural behaviour of horses is discussed at the hand of the literature and the...
Hawkins JF, Fessler JF.To evaluate efficacy of debridement for treatment of supraspinous bursitis in horses and to evaluate the outcome. Methods: Retrospective study. Methods: 10 horses with clinical signs of supraspinous bursitis. Methods: Medical records were reviewed for signalment, anamnesis, results of physical and radiographic examination, microbial culture results of supraspinous bursa tissue or exudate, Brucella abortus titers, type of antimicrobial and anti-inflammatory therapies, surgical technique, complications of the surgical procedure, and findings on histologic examination of excised nuchal ligament a...
Derksen FJ, Scott JS, Slocombe RF, Robinson NE.We determined the effect of IV administered beta 2-adrenergic receptor agonist clenbuterol on pulmonary function and on the response to histamine in 12 healthy ponies. Measurements were made at base line and after saline solution or clenbuterol was administered IV at a dosage of 0.2, 0.8, or 1.6 micrograms/kg. The dosage of clenbuterol used in each study was unknown to the investigators until all the data had been analyzed. Intravenous administration of saline solution or clenbuterol did not alter base-line pulmonary function significantly. Aerosol histamine administration significantly decrea...