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.
Adams OR, Schneider RK, Bramlage LR, Easley KJ, Schneider JE.Suprascapular nerve decompression has proven to be a useful treatment for refractory neuropraxia in horses. The surgical procedure used to effect that decompression is described. The surgery can be undertaken when conservative treatment has failed, but the sooner the surgery is done, the more likely the muscle mass is to be cosmetically satisfactory.
Collier MA, Rendano VT, Kallfelz FA.A delayed union metacarpal stress fracture was repaired in a horse, using lag-screw fixation in conjunction with dc electrical stimulation. Twelve weeks after surgery, radiographic and scintigraphic evaluations revealed that the fracture line was not discernible and that there was a decrease in radiopharmaceutic uptake, as compared with that in previous bone imaging studies. In this horse, DC stimulation of a delayed union stress fracture in a bone resulted in a healing pattern similar to that in human beings with delayed union fractures when treated with electrical stimulation.
Held JP, Patton CS, Toal RL, Geiser DR.A thyroid carcinoma was diagnosed in a 14-year-old competitive trail horse with a 3-month history of work intolerance. Abnormal findings included low base-line triiodothyronine (T3) and thyroxine (T4) values, a large thyroid gland and decreased work tolerance. Nuclear medicine scanning revealed displacement of the right thyroid gland by a mass. Needle biopsy of the mass revealed neoplastic changes compatible with thyroid carcinoma. After removing the tumor surgically, T3 and T4 values returned to normal. Subsequently, the horse was able to compete successfully. Horses with work intolerance com...
Schneider JE, Adams OR, Easley KJ, Schneider RK, Bramlage LR, Peter J, Boero MJ.Supraspinatus and infraspinatus muscle paralysis with atrophy was treated by partial osteotomy of the scapula, deep to the suprascapular nerve. The horses had various gait abnormalities, which were corrected by the surgery, but regeneration of the muscles varied from partial to complete, depending on the duration of the condition and the degree of atrophy before surgery.
Olson NC, Meyer RE, Anderson DL.The effects of endotoxemia on cardiopulmonary parameters, before and after cyclooxygenase blockade, were determined in anesthetized ponies spontaneously breathing a mixture of halothane and 100% O2. Escherichia coli endotoxin was infused intravenously at 20 micrograms/kg for 1 h followed by 10 micrograms X kg-1 X h-1 the subsequent 4 h. By 15 min endotoxin increased mean pulmonary arterial pressure (Ppa), pulmonary vascular resistance (PVR), and alveolar dead space ventilation (VDA/VT), and these were followed by a return to base-line values by 30 min. A second increase in PVR occurred by 5 h ...
MacHarg MA, Bottoms GD, Carter GK, Johnson MA.Adrenocortical function was assessed in horses given multiple IM doses of dexamethasone to determine the duration of adrenocortical suppression and insufficiency caused by 2 commonly used dosages of dexamethasone (0.044 and 0.088 mg/kg of body weight). Dexamethasone was administered at 5-day intervals for a total of 6 injections. Daily blood samples were collected. The plasma was frozen and later assayed for cortisol. An ACTH response test was determined 2 days before the first injection of dexamethasone and again 8 days after the last dexamethasone injection. Maximum suppression of plasma cor...
Easley JR.The erythrogram (erythrocyte histogram) and red cell distribution width (RDW) were evaluated in 5 purebred horses and 1 pony of mixed breeding with experimentally induced anemia. Four horses were studied for 6 weeks after 20% of their estimated blood volume was removed on each of 2 consecutive days (40% total blood loss; acute blood-loss group). Two horses were given acetylphenyl hydrazine IV daily, until acute Heinz body hemolytic anemia was induced; the 2 horses were then evaluated for 6 weeks. One horse and the pony had 20% of their estimated blood volume removed via phlebotomy once each we...
Parma AE, Santisteban CG, Villalba JS, Bowden RA.Horses inoculated with either equine cornea or killed Leptospira interrogans serovars pomona, tarassovi, icterohaemorrhagiae, wolffi and hardjo, developed corneal opacity and produced antibodies which made it possible to demonstrate partial antigenic identity between equine cornea and four of those serovars employed. These antibodies were isolated by means of immunoadsorptions, purified by ion-exchange chromatography (DEAE-Sephadex A-50) and run by immuno-electrophoresis in agar gel. Both antibodies, anti-equine cornea and anti-leptospira, showed that they corresponded to the IgGb subclass. Th...
Lavach JD, Sullins KE, Roberts SM, Severin GA, Wheeler C, Lueker DC.Twenty-six horses and five mules with periocular sarcoids were treated with intralesional injections of a purified bacillus of Calmette and Guerin (BCG) cell walls in oil suspension. All sarcoids were cured and the horses and mules remained free from recurrence of sarcoid during the two-year follow-up period.
Olson NC.Effects of endotoxemia on lung water, hemodynamics, and gas exchange were determined in ponies breathing a mixture of halothane and 100% O2. Escherichia coli endotoxin was infused IV at 20 micrograms/kg of body weight for 1 hour followed by 10 micrograms/kg/hr the subsequent 4 hours. By 0.25 hour, endotoxin increased mean pulmonary artery pressure and pulmonary vascular resistance; this was followed by a return to base-line values by 0.5 and 1 hour, respectively. A 2nd increase in pulmonary vascular resistance occurred by 5 hours of endotoxemia. During the last 2 hours of endotoxin infusion, c...
Anderson NV, DeBowes RM, Nyrop KA, Dayton AD.Twelve horses comprised 3 treatment groups; all horses in 2 of the groups had recently been transported and had clinical and laboratory evidence of respiratory tract infection, with equine influenza type 2 virus being the principal pathogen. Mononuclear phagocytes and other leukocytes from blood, lung, and peritoneal cavity were studied in phagocytosis and erythrocyte-antibody (EA) rosette assays. Total numbers of pulmonary alveolar macrophages were increased over control values in bronchoalveolar lavage (BAL) fluid of group 3 horses after recovery from influenza (P less than 0.02), whereas th...
Derksen FJ, Scott JS, Miller DC, Slocombe RF, Robinson NE.We performed bronchoalveolar lavage (BAL) in 2 groups of ponies. Principal ponies had a history of heaves, a disease characterized by recurrent airway obstruction and airway hyperreactivity when ponies are housed in a barn and fed hay; control ponies had no history of airway obstruction. Ponies were paired (principal and control), and BAL was performed after 2 months of being pastured when principal ponies were in clinical remission (Period A), after barn housing when principal ponies had acute airway obstruction (Period B), and after a 1- and a 2-wk recovery phase of pasture grazing (Periods ...
Czlonkowska M, Boyle MS, Allen WR.Fourteen horse embryos recovered non-surgically on Days 6-8 after ovulation (Day 0) were cooled slowly to - 35 degrees C (7 embryos) or - 40 degrees C (7 embryos) and stored in liquid nitrogen (- 196 degrees C) for 4-98 days. Surgical transfer of the thawed embryos to unmated recipient mares that had ovulated - 2 to + 1 days with respect to the embryo donors resulted initially in the establishment of 4 conceptuses. However, only one mare maintained her pregnancy to term.
Costa G, Labadia A, Garcia-Sacristan A.The effects of verapamil, a calcium antagonist agent, were studied on smooth muscle preparations of the lower urinary tract of horses. Verapamil (2 X 10(-4) to 2 X 10(-8) M) relaxed the ureter, urethra and urinary bladder preparations contracted by potassium (127 mM), L-noradrenaline (2 X 10(-5) M), histamine (2 X 10(-5) M) and acetylcholine (2 X 10(-5) M). These results allow the conclusion that verapamil has a dose-dependent relaxing effect on smooth muscle of the lower urinary tract.
Macpherson ML, Giguère S, Pozor MA, Runcan E, Vickroy TW, Benson SA, Troedsson MHT, Hatzel JN, Larson J, Vanden Berg E, Kelleman AA, Sanchez LC....Eleven pregnant pony mares (D270-326) were administered ceftiofur sodium intramuscularly at 2.2 mg/kg (n = 6) or 4.4 mg/kg (n = 5), once daily. Plasma was obtained prior to ceftiofur administration and at 0.5, 1, 2, 4, 8, 12, and 24 hr after administration. Eight pony mares were re-enrolled in the study at least 3 days from expected foaling to ensure steady-state concentrations of drug at the time of foaling. Mares were administered ceftiofur sodium (4.4 mg/kg, IM) daily until foaling. Parturition was induced using oxytocin 1 hr after ceftiofur sodium administration. Allantoic and am...
Murray RC, Gaughan EM, DeBowes RM, Mosier DA, Hoskinson JJ.Biaxial palmar digital neurectomy of all limbs was performed on 6 mixed-breed castrated adult male horses, using a standard guillotine method. Using a Teflon catheter, 20 mg (2 ml) of sodium hyaluronate (group 1), 2 ml of phosphate-buffered saline solution (group 2), or catheter placement with no infusion (group 3) was applied to 4 (group 1) or 2 (groups 2 and 3) of 8 incisions/horse. Treatments were administered after closure of the neurectomy incision, and the catheter was removed. Horses were evaluated daily for 1 week, then weekly over a 9-week period for evidence of lameness, swelling, an...
Sakurai M, Isshiki S, Sasaki N, Sakai Y, Yamada Y, Morimoto M.A 7-year-old male Thoroughbred horse exhibited recurrent falls followed by convulsive seizures. The horse was clinically diagnosed with epilepsy and phenobarbital treatment was initiated. However, as seizure control was unsuccessful, the animal was euthanized. At necropsy, yellow-brown linear lesions were found extensively at the U-fibres and cingulate gyrus within the cerebral white matter. Histopathologically, linear demyelination and occasional cavitation were observed. Glial cells with yellow-brown pigment granules, which were autofluorescent, positive to the periodic acid-Schiff reaction ...
Douglas RH, Ginther OJ.Nine groups of pony mares (3/group) were used in a 3 times 3 factorial experiment. The factors were dose of PGF-2 alpha (0, 0.25 of 1.25 mg and route of administration (im, iu or il). Mares were laparotomized and treated on day 7 postovulation. Jugular blood was collected for progesterone RIA at 0 (pretreatment) and 1,6,12,24,48, and 72 hr posttreatment. In mares given either 0.25 mg or 1.25 mg PGF-2alpha, progesterone concentrations were not significantly different among the three routes at any of the posttreatment times studied except at 6 hr posttreatment. In mares given 0.25 mg, progestero...
Odenkirchen S, Huskamp B.Casuistics of 200 patients with acute diarrhea (72 horses with salmonellosis, 55 horses with typhlocolitis, 73 horses with unspecific diarrhea) have been analyzed. It was shown, that horses with salmonellosis have been fallen ill with a primary disease for a longer period of time before the beginning of diarrhea than those with typhlocolitis and that in cases of salmonellosis antibiotics very often were used during the preliminary treatment. Frequently a primary illness of the colon was seen with typhlocolitis. Besides the frequent use of butylscopolamin during the pretreatment was noticed. Th...
Kofler J, Kübber-Heiss A, Schilcher F.Clinical, ultrasonographic and pathological findings of a cutaneous, multilocular T-cell lymphosarcoma (malignant lymphoma) in a 13-year-old, brown Austrian warmblood mare are reported. The horse was under clinical observation, and the tumours were sonographically monitored over an 8 month period, revealing worsening of body condition, weight loss, lameness of the left hindlimb and a slight increase in the tumours size. Most of the tumours were covered by normal skin, one showed ulceration. Ultrasonography of the tumours allowed accurate anatomical localization in relation to the adjoining tis...
May-Davis S, Vermeulen Z, Hunter R, Brown W.For over 200 years, equine anatomic literature has chiefly portrayed the attachment points of the nuchal ligament lamellae (NLL) from the second to the seventh cervical vertebrae (C2-C7). However, recent studies have shown that the modern domestic horse, Equus caballus, primarily exhibits the attachments points from C2-C5. Here we present the rare finding of a complete NLL attached from C2-C7 in one Australian Stock Horse (ASH) and discuss the potential implications of these findings. Previously, this trait has only been confirmed among close descendants of Equus ferus ferus; namely the primi...
Gehlen H, Bubeck K, Rohn K, Stadler P.The aim of this study was to investigate the potential haemodynamic effects of valvular insufficiency and recurrent airway obstruction (RAO) in horses with atrial fibrillation (AF). Therefore in ten healthy horses (group 1) and 40 horses with AF a clinical examination, a lung examination, echocardiography and right heart catheterization for measurement of intracardic and pulmonary pressures were performed. According to the clinical findings the horses with AF were subdivided into 4 groups (group 2: AF; group 3: AF/valvular insufficiency; group 4: AF/RAO; group 5: AF/valvular insufficiency/RAO)...
Rinnovati R, Xenos S, Beltrame A, Marigo A, Forni G, Morini M.A neurofibroma was excised from the subcutis on the medial side of the left thigh of a 15-year-old Warmblood gelding, which had shown lameness of the left hind limb. No other source of lameness was found. Two weeks after surgery, the horse was sound at a lameness examination.
Lloyd KC, Wheat JD, Ryan AM, Matthews M.Sudden onset of hematuria was associated with mucosal ulceration of the proximal portion of the urethra in 1 stallion and 3 geldings. Hematuria was observed characteristically and consistently at the end of urination. Mucosal ulceration was identified endoscopically in the proximal portion of the urethra at the level of the ischial arch. Biopsy of an ulcerated area of the proximal urethra in one gelding revealed transitional cell carcinoma. Treatment regimens varied from systemic antimicrobial and/or vasoactive therapy to diversion of urinary flow via a temporary perineal urethrostomy. Hematur...
Ebrahimi M, Hamidinejat H, Tanabandeh MR, Razi Jalali MH, Rasouli A.Diversity among the pathogenic strains of Theileria equi (T. equi), a major agent of equine piroplasmosis, can affect the appropriate detection of parasite and host immunization. Production of recombinant surface proteins from an infected horse in natural endemic area provides a reliable tool for immunodiagnosis of parasite. Regarding this, the present study was targeted toward the cloning, expression, and purification of the immunogenic regions of equine merozoite antigen 1 (EMA-1 gene), as one of the most important immunodominant surface proteins in T. equi, from naturally infected horses in...
López ML, Fuentes P, Retamal C, De Souza W.The occurrence, localization and ultrastructural characteristics of a blood-tissue barrier throughout the stallion proximal seminal excurrent duct system were studied by the exclusion of electron-dense tracers and freeze-fracture techniques. Striking differences were observed in the distribution of lanthanum tracer and in the geometrical organization of the zonulae occludentes along the ductus efferentes, epididymides and vas deferens. The zonulae occludentes domain, the principal structural component of the blood-epididymis barrier, differed in permeability, width and strand numbers along the...
Maney JK, Dzikiti BT, Escobar A, Knych HK, Bennett RC.Morphine is the prototypical μ-opioid receptor agonist used to provide analgesia in veterinary species. Its effects are well-described in horses but not donkeys. Objective: To determine the antinociceptive effects of two doses of morphine in donkeys. To describe preliminary pharmacokinetic parameters of morphine in donkeys. Methods: In vivo experiment. Methods: Eight adult castrated male donkeys were given intravenous (IV) 0.9% saline, morphine 0.1 mg/kg bwt (LDM), or morphine 0.5 mg/kg bwt (HDM) in a randomised order with a minimum 1-week washout period. Mechanical nociceptive thresholds (...
Spier SJ, Meagher DM.Rational perioperative management improves the success rate of abdominal surgery. Important aspects of management are discussed, including principles of fluid therapy, nutrition, intravenous catheterization, antimicrobial prophylaxis, and the use of nonsteroidal anti-inflammatory medication. Current advances in the area of immunotherapy are mentioned.
Wintzer HJ.A long-term treatment with biotin (vitamin H) in 5 warm-blooded horses and 10 trotter horses is reported. The dose of 0.031-0.037 mg/kg body weight was well tolerated, and with a therapy period up to 10 months an improvement of the horn quality of the growing hoof could be attained as it had not been possible before with other measures. Biotin (Gabiotan) is recommendable as a therapeutic in all cases of hoof problems which are based on disturbed horn elasticity.
