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.
Cabler P, Geddes LA, Rosborough J.Ultrasonic energy, provided by a commercially available water vaporizer, was used to vaporize methoxyflurane, halothane, and chloroform. The vaporizer was placed directly in the respiratory line, and the anaesthetic liquid was vaporized one drop at a time. Anaesthesia was maintained for periods up to 6 hr in horses, ponies, calves, sheep, dogs, and one pig. This method of vaporizing liquids is applicable to a wide variety of anaesthetics. It is easily controlled, and the same vaporizer can be used with a wide range of sizes of subjects. The vaporizer can be placed directly in the respiratory c...
Brown DG.Physiologic responses of irradiated and nonirradiated Shetland Ponies to controlled exercise were measured over a period of 5 years. The 5-year test began when the ponies were 3 years old and 5 months after they were exposed to 650 R of 60-Co gamma radiation. Significant differences in heart rates, respiratory rates, and rectal temperatures were demonstrated between irradiated and nonirradiated ponies when subjected to exercise and high ambient temperatures. Inthe irradiated group, heart rates were usually slower, especially during recovery immediately after exercise, and respiratory rates and...
Scott EA.A weanling Quarter Horse filly developed ventral swelling of the lower cervical area after difficult passage of a stomach tube for deworming. Intermittent bilateral nasal discharge developed. Radiography revealed fluid and gas density dorsal to the trachea and esophagus. Surgical incision with drainage and debridement of the abscess and fistulous tract, facilitated by use of drains, led to complete recovery. Contrast medium injected after surgery demonstrated a communication between the abscess and the pharyngeal region.
Rossdale PD.The place of clinical research in the veterinary profession is discussed against the author's personal experiences and in the context of how research workers, clinicians, teachers and veterinary students might be brought into a more cohesive unit through the development of a Faculty of clinical research and experimental medicine. It is argued that students should receive training in research and teaching and that efforts should be made to break down the attitude of "them" and "us" which tends to separate the clinicians and academics.
Beckett SD, Walker DF, Hudson RS, Reynolds TM, Purohit RC.A needle-tipped catheter or subminiature pressure transducer was implanted in the corpus spongiosum penis (CSP) of Shetland Pony stallions to determine pressure during coitus. Electrodes for monitoring the electromyographic (EMG) activity were implanted in the ischiocavernosus (IC) and bulbospongiosus (BS) muscles. The mean peak CSP pressure recorded with the catheter was 762 mm of Hg, and with the subminiature pressure transducer, it was 994 mm of Hg. The simultaneous occurrence of the CSP pressure peaks and bursts of BS muscle activity indicated that these muscles were the likely source of e...
Barrett MW, Chalmers GA.To determine the exposure of free-ranging pronghorns (Antilocapra americana Ord) to selected pathogens, serum samples were obtained from 33 live-trapped animals from southwestern Saskatchewan in 1970, and from 26 and 51 animals from southeastern Alberta, in 1971 and 1972, respectively. Antibodies were found to the agents of parainfluenza 3, bovine virus diarrhea, eastern and western encephalomyelitis, infectious bovine rhinotracheitis and the chlamydial group. No serologic reactors were found to the agents of bluetongue, epizootic hemorrhagic disease, brucellosis, or leptospirosis (4 serotypes...
Sisodia CS, Kramer LL, Gupta VS, Lerner DJ, Taksas L.Pharmacological disposition of chloramphenicol was studied in horses. Minimum levels of the antibiotic (greater than or equal to 5 mu g/ml) in blood or plasma recommended to combat infections could not be achieved by 4.4 and 8.8 mg/kg I.V. or 30 and 50 mg/kg I.M. or 30 mg/kg oral (as palmitate salt) doses of chloramphenicol. Increasing the dose to 19.8 and 26.4 mg/kg I.V. provided such levels for about two and three hours respectively. A combination of 20 mg/kg I.V. and 30 mg/kg I.M. administered simultaneously did not provide more prolonged levels than 26.4 mg/kg I.V. alone. Chloramphenicol s...
Drudge JH, Lyons ET, Tolliver SC.Three formulations of cambendazole were evaluated for anthelmintic activity by critical testing method in 21 horses. Cambendazole suspension was administered via stomach tube at the dose rate of 10 mg/kg to 3 horses and at the dose rate of 20 mg/kg to 3 horses. Cambendazole paste was given intraorally to 8 horses, and the pellet formulation was fed to 7 horses at the dose rate of 20 mg/kg. Anthelmintic activity of cambendazole was similar for all dose rates and formulations. Gasterophilus intestinalis, Gasterophilus nasalis, Draschia megastoma, Anoplocephala perfoliata, and Anoplocephala magna...
Hughes JP, Kennedy PC.TWo cases of XO-gonadal dysgenesis in the mare are presented. Case No 1 was a pure 63, XO, while Case No 2 was a mosaic with a preponderance of XX cells. The clinical picture was one of phenotypically normal female mares with small uteri and infantile ovaries. The ovaries lacked germ cells, and consisted of stroma only. This study emphasizes the importance of chromosome analysis in providing information concerning the mechanisms involved is some cases of equine infertility.
Rawlings CA, Bisgard GE, Dufek JH, Buss DD, Will JA, Birnbaum ML, Chopra PS, Kahn DR.Prolonged extracorporeal membrane oxygenation (PEMO) was performed in 6 adult ponies with the membrane oxygenator in vein-to-artery bypass circuit. A flow rate equal to 46 per cent of control cardiac output was diverted through the PEMO circuit of 10 to 24 hours. Three of the 6 ponies were perfused for at least 20 hours and developed no complications. Immediately following initiation of PEMO, left ventricular output decreased; however, in the interval between 6 and 24 hours, left ventricular output was increased above control levels. Aortic pressure and left ventricular work were markedly elev...
Jackson RK.The structural differences in the spine of the horse and man are compared. These, together with the different uses to which the spine is put, explain the different patterns of disease. Impingement of the spinous processes is discussed in detail including surgical treatment. Comments are also made on sacroiliac strain and manipulation of the spine.
Datt SC, Usenik EA.Physical signs and blood changes were studied in horses with artificially produced obstructions of the duodenum and the small colon and simulated volvulus of the ileum. Horses with obstruction of the duodenum had the most violent physical signs and the shortest survival time. Blood changes were an initial rise in pH followed by acidosis, hyperkalemia and a decrease in HCO3 minus, Na+ and C1 minus. Obstruction of the small colon resulted in mild physical signs. The blood parameters recorded were normal. Simulated volvulus resulted in continuous colic. Blood changes were acidosis and hyperkalemi...
Jones RS.Surgical repair of a cleft palate was carried out in three horses. Mandibular symphisotomy allowed adequate exposure of the defect. The first subject, a young foal died from inhalation pneumonia but the other two made satisfactory recoveries. The problems of closure of the lip and symphysis are discussed.
Crowhurst RC.Diseases of the back of horse and man are not comparable owing to the great difference in anatomy and posture. Veterinary surgeons, particularly in the United Kingdom, are often requested to account for a poor performance due to suspected "back trouble" but a complete examination of the horse's back is most difficult and care must be taken first to exclude any limb or foot lesions. Diseases of the bones, nerves and muscles are briefly discussed. Diagnosis must be improved by new radiographic and biochemical tests before the significance of back lesions can be assessed or even treated.
Ricketts SW.The author describes a technique for obtaining endometrail biopsy specimens from mares. the noraml cyclincal histology of the endometrium and anarbitarry classification histology of the endometrium and an arbitarary classification of the histopathology seen in endometrial biopsy speciemens. Previous literature on the subject is cited. Results of endometrial biopsies taken by the author from 134 barren mares, with histories of subfertility are descirbed and classified. The use of the technique and the interpretationof its find ings in relation to reproductive performance is discussed.
Bhavnani BR, Martin LJ, Baker RD.A mixture of 1-14C-isopentenylpyrophosphate and 3H-dehydroisoandrosterone was injected into a horse fetus intramuscularly during laparotomy, after which maternal urine was collected for 4 days. Steroid conjugates in the urine were extracted with Amberlite XAD-2 resin, hydrolysed and separated into phenolic and neutral fractions. From the phenolic fraction estrone, 17alpha-estradiol, equilin and equilenin were isolated. Only estrone and 17alpha-estradiol contained both 3H and 14C, while the ring B unsaturated estrogens contained only 14C. From the neutral fraction 14C-labeled 3beta-hydroxy-5alp...
DiPietro JA, Todd KS, Reuter-Dallman V.Ivermectin given IM at 200 micrograms/kg, alone or in combination with procaine penicillin G at 600 IU/kg, to 20 randomly selected young horses of various breeds reduced fecal strongyle egg counts from 400-4100 epg (avg greater than 1000) pretreatment to zero 7 days posttreatment. There were no systemic or injection-site reactions, either immediate or delayed, in any of the horses.
Luo T, Bertone JJ, Greene HM, Wickler SJ.In its FDA approved formulation, N-butylscopolammonium bromide (Buscopan Injectable Solution, Boehringer Ingelheim Vetmedica) is an anticholinergic spasmolytic agent indicated for management of abdominal pain associated with spasmodic colic, flatulent colic, and simple impactions in horses. Use of this drug ablates gastrointestinal peristalsis and rectal pressure. It ahs been suggested that N-butylscopolammonium bromide could be used to facilitate rectal examinations in horses. This study compared the effects of N-butylscopolammonium bromide versus lidocaine and a saline control on rectal pres...
Barclay WP, McCracken RJ, Phillips TN, Foerner JJ.Chronic nongranulomatous intestinal inflammation was found during laparotomy in 7 horses. The clinical signs consisted of recurrent abdominal pain in all horses. Anti-inflammatory agents (corticosteroidal and nonsteroidal agents) appeared to be effective for controlling the signs. Surgical removal of the involved intestine also was effective. Nonocclusive or temporary mesenteric ischemia was proposed as a cause of the intestinal lesions.
Griffin PG, Ginther OJ.Fetal activity and mobility and changes in diameter of the allantoic fluid compartment in the uterine horns were studied in mares between days 69 and 81 of pregnancy by use of transrectal ultrasonography (n = 12) and transcervical videoendoscopy (n = 8). The insertion tube of the videoendoscope was positioned within the allantoic sac to permit viewing of the fetus and entrance to each uterine horn. Each uterine horn was divided ultrasonographically into 3 segments of equal length, and the horns were designated on the basis of side of umbilical attachment (cord vs noncord horns). The diameter o...
Zamos DT, Honnas CM, Hoffman AG.Arthroscopic examination of structures within the plantar pouch of the tarsocrural joint was accomplished via portals in both the plantaromedial and plantarolateral aspects of the joint. Flexion and extension of the tarsus while examining the joint through either portal allowed observation of the proximal and plantar aspects of the lateral and medial trochlear ridges, the trochlear groove, the caudal aspect of the distal tibia, and the deep digital flexor tendon (DDFT) in its sheath. From a plantarolateral portal, the plantar talocalcaneal ligament and the plantar aspect of the lateral malleol...
Pinchbeck GL, Clegg PD, Proudman CJ, Morgan KL, French NP.A concurrent case-control study of 12 UK racecourses was made between March 1, 2000, and August 31, 2001, to identify and quantify the factors associated with the risk of horses falling in steeplechase races. Cases were defined as a jumping effort at a steeplechase fence that resulted in a fall and controls were defined as a successful jumping effort over any steeplechase fence at any of the 12 racecourses within 14 days before or after the case fall. Information on the horse, the jockey and the race were collected and all the fences on all the courses were surveyed. Conditional logistic regre...
Mayhew IG.Evaluation of horses for eye problems and for suspected impairment of visual acuity often requires a thorough neuroophthalmic examination to be conducted. Along with a full ophthalmic evaluation, the results of such an examination should indicate the likely site of any lesion(s) accounting for blindness, miosis, mydriasis, anisocoria, Horner's syndrome, strabismus, facial paralysis and facial spasm, nystagmus and other signs of vestibular disease, and cerebellar disorders, that may be present. Such a thorough examination with guidance for correct interpretation of findings is given here.
Lyon RM, Macauley B, Richardson S, de Coverly R, Russell M.Horse riding is a common leisure activity associated with a significant rate of injury. Helicopter emergency medical services (HEMS) may be called to equestrian accidents. Accurate HEMS tasking is important to ensure appropriate use of this valuable medical resource. We sought to review HEMS response to equestrian accidents and identify factors associated with the need for HEMS intervention or transport of the patient to a major trauma centre. Methods: Retrospective case review of all missions flown by Kent, Surrey & Sussex Air Ambulance Trust over a 1-year period (1 July 2011 to 1 July 20...
Ball BA, Brinsko SP, Thomas PG, Miller PG, Ellington JE.Development of 1- to 2-cell in vivo fertilized equine embryos cultured with or without uterine tubal epithelial cells (UTEC) was studied. One- to 2-cell embryos (n = 26) were collected surgically from the uterine tubes of pony mares 1 day after ovulation. Four- to 8-cell embryos (n = 9) were collected 2 days after ovulation. Presumptive zygotes and 2-cell embryos were cultured with (n = 17) or without (n = 9) UTEC, and all 4- to 8-cell embryos were cocultured with UTEC as positive controls. Uterine tubal epithelial cells were used as cell suspensions within 2 weeks after initiation of cultures...
Barrett EJ, Munsterman AS, Hanson RR, Jackson RL.To compare in vitro strength and failure characteristics of a tendon implant against a 3 loop pulley suture pattern for equine superficial digital flexor tendon (SDFT) laceration repair. Methods: Experimental. Methods: Cadaveric equine forelimb SDFT (n = 16). Methods: One tendon of each of 8 pair of SDFT was randomly selected for repair with either the 3-loop pulley (3LP) suture pattern using 2 polydioxanone or with 4 stainless steel suture and anchor implants (SA). Ultimate load to failure, mode of failure, gap at failure, and load to 2 mm gap were obtained using a materials testing sys...
Withrow JM, Sargent GF, Scheffrahn NS, Kesler DJ.Two pony mares were administered 150 mg of testosterone propionate every other day for 20 days (ten injections) and every ten days there-after. An additional two mares and one stallion were not treated and served as controls. Testosterone propionate was dissolved in absolute ethanol and administered subcutaneously. Sex behavior tests were conducted 26 and 40 days after the first injection. Control mares exhibited very little male sex behavior. Both testosterone propionatetreated mares, however, exhibited mounting, sniffing, flehmen, biting and vocalization behavior in the presence of an estrou...
Fenwick SJ, Hincks PR, Scarth JP, Wieder ME, Hillyer LL, Paine SW.Salmeterol is a man-made beta-2-adrenergic receptor agonist used to relieve bronchospasm associated with inflammatory airway disease in horses. Whilst judicious use is appropriate in horses in training, they cannot race with clinically effective concentrations of medications under the British Horseracing Authority's Rules of Racing. Salmeterol must therefore be withdrawn prior to race day and pharmacokinetic (PK) studies used to establish formal detection time advice. Salmeterol xinafoate (Serevent Evohaler ) was administered (0.1 mg twice daily for 4.5 days) via inhalation to six horses. Ur...
Jacob RJ, Steiner MR.Equine herpesvirus 3 (EHV-3)-infected equine cells display a kinetics of infected cell polypeptide (ICP) synthesis at 34 degrees C that is typical of coordinate cascade gene regulation of herpesviruses. In contrast, when infected cell cultures are incubated at the restricted temperature of 39 degrees C, the shift from early (beta) gene expression to late (gamma) gene expression is perturbed, i.e., there is an accumulation of early (beta) gene products and a decrease in, or absence of, late (gamma) gene products. Some of the affected late (gamma) gene products may be glycoproteins since these I...
Britton BA.Cervical and endometrial swabs were taken from 7 mares at various stages of the oestrous cycle. There was no consistent pattern of cell change throughout the cycle. The dominant cell in smears from normal mares was the columnar epithelial cell, especially in smears obtained during oestrus. A ciliated columnar epithelial cell was found much less frequently but appeared more often in smears before oestrus. Endometrial biopsies were also collected from 7 mares at intervals 2-3 weeks over an 8-month period from the beginning of spring to the end of autumn. There was no obvious change in the endome...
Sweeney RW.Malassimilation should be suspected in horses with weight loss in spite of a good appetite. Malassimilation is usually confirmed with oral glucose or D-xylose absorption tests, whereas the oral lactose tolerance test can be used to evaluate lactase deficiency in foals. Once malassimilation is confirmed, other diagnostic tests such as abdominocentesis, rectal mucosal biopsy, or exploratory laparotomy with intestinal biopsies may determine the etiology of malassimilation.
Varma KJ, Powers TE, Powers JD.A single-dose pharmacokinetic study of chloramphenicol in propylene glycol was done in 6 horses after 22 mg/kg was administered IV. Serum drug concentrations obtained at various predetermined intervals were determined by an electroncapture gas-chromatographic technique. The time-concentration data were described by a 2-compartment open model, and various pharmacokinetic variables were estimated. The median elimination rate constant was estimated to be -0.0185 minute-1 (-0.0225 to -0.0148 minute-1), and the median half-life was 37.36 minutes (30.74 to 46.90 minutes). The median apparent volume ...
