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.
Greet TR.The case histories of three young thoroughbred racehorses with displaced lateral condylar fractures combined with an axial fracture of the lateral sesamoid bone are described. In two cases the condylar fracture was repaired surgically but both horses developed severe degenerative joint disease and remained lame. The third horse was destroyed humanely. It is important that axial fractures of the sesamoid bone are recognised so that a poorer prognosis can be given for treatment of condylar fractures in racing thoroughbreds.
Hultgren BD, Zack PM, Pearson EG, Kaneps AJ.A juvenile granulosa cell tumour is described in a 3-month-old Arabian filly. The 32 X 27 X 27 cm tumour had replaced the right ovary. The neoplasm was composed of multiple nodules of neoplastic granulosa cells which formed microfollicles, macrofillicles and cysts, as well as solid nests and trabeculae. The supporting stroma contained theca cells. Mixing of the neoplastic granulosa cells and theca cells in disorderly fashion was noted. The diagnosis was based on age of occurrence and histological appearance.
Bertone AL, McIlwraith CW, Jones RL, Norrdin RW, Radin MJ, Lebel JL.To evaluate the effects of 5 treatments on clinical responses, synovial fluid analysis, radiographic changes, bacteriologic culture results of the synovial fluid and synovial membrane, microscopic characteristics of the synovial membrane, and articular cartilage histochemistry, Staphylococcus aureus organisms (1.6 X 10(6) colony-forming units) were inoculated into the tarsocrural joints of 12 horses (n = 24 joints; 2 joints/horse). Each horse was given phenylbutazone (2 g) orally, every 24 hours, beginning 24 hours after inoculation. Two horses (ie, 4 joints) were not given other treatment (co...
Engelking LR, Blyden GT, Lofstedt J, Greenblatt DJ.Previous studies demonstrated that plasma clearance of organic anions such as bilirubin, bile acid, sulfobromophthalein (BSP) and indocyanine green (ICG), was reduced from 36% (bile acid) to 55% (ICG) in fasted (3 days) horses. It is believed that a general decline in carrier-mediated hepatic uptake may have accounted for those changes. However, fasting may also affect hepatic blood flow, thereby contributing to reduced clearance of these compounds. In order to test this hypothesis, plasma clearance of antipyrine, acetaminophen and lidocaine, drugs known to be cleared by the liver yet not susp...
Francl AT, Amann RP, Squires EL, Pickett BW.The effects of extender and storage at 20 degrees C on equine spermatozoa were evaluated in two experiments using embryo recovery as the end point. In both experiments, inseminations were every other day, starting on Day 2 or 3 of estrus or after a 35-mm follicle was detected, with 250 x 10(6) progressively motile cells (based on initial evaluation). In Experiment 1, semen from two stallions was used to compare the motility and fertility of spermatozoa maintained in a) heated skim milk extender at 37 degrees C with insemination in <1 h; b) E-Z Mixin extender at 37 degrees C with inseminatio...
Whitlock MR, Whitlock J, Johnston B.A retrospective study of horse riding injuries in Berkshire was undertaken over a one year period from November 1983. The information was obtained from the Ambulance Service, the Jockey Club and the St. John Ambulance Brigade. There was a total of 103 injured persons with no deaths. Information from the Jockey Club was compared with the other two groups, the former sustaining more limb injuries and the latter more head injuries. A questionnaire was sent to all 42 ambulance patients. Thirty-eight had radiographs taken, 16 of which showed a fracture. Forty-one were wearing some form of hard hat,...
Waterman AE, Robertson SA, Lane JG.The metabolism and distribution of ketamine and its two major metabolites (norketamine and dehydronorketamine) was investigated in 10 horses undergoing airway surgery. Following premedication with xylazine (1.1 mg kg-1 intravenously) anaesthesia was induced by the rapid injection of ketamine at a dose of 2.2 mg kg-1 intravenously. Anaesthesia was maintained with halothane vaporized in oxygen and nitrous oxide (50:50). Serially collected blood samples were analysed by a sensitive gas liquid chromatographic technique. Plasma ketamine concentrations declined biexponentially with a rapid initial d...
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 ...
Bukowiecki CF, Bramlage LR, Gabel AA.Forty-eight limbs of 12 freshly euthanized horses were used to generate data on the strength of the equine suspensory apparatus. The point of failure of the suspensory apparatus of each limb was determined. Immediately before euthanasia, 6 of the 12 horses (thoroughbreds and standardbreds) had been engaged in active training or racing, and six horses in stall and/or pasture activity. In the actively training or racing horses, the point of acute failure of the suspensory apparatus was within the proximal sesamoid bones in 20 (83%) limbs (resulting in 17 apical fractures, 2 basilar fractures, an...
Coyne CP, Kelly AB, Hornof WJ, O'Brien TR, Philp MS, Lamb JF.A method is presented for the in vitro isolation and radiolabeling of equine platelets with the isotope indium 111 (111In: half-life = 2.8 days, gamma = 173 keV, 89%; 247 keV, 94%). The technique described involves complexing 111In with the lipid-soluble chelating agent, 2-mercaptopyridine-N-oxide (merc), in an aqueous medium. 111In-merc platelet-labeling efficiencies in autologous plasma pretreated with or without ferric citrate reagent were 82 +/- 7% and 24 +/- 12%, respectively. Mean intravascular survivals of 111In-merc-radiolabeled platelets in 8 healthy horses according to simple linear,...
Fuchs R, Militz H, Hoffmann M.The ascertainment of the digestibility of crude nutrients in rations for horses requires the inclusion of movement-based performance as influencing factor. Under the consideration of this requirement, indicator methods gain significance in comparison with the standard method of collecting faeces completely. In two experiments the digestion of the crude nutrients in rations for horses was tested according to the standard method (complete collection of faeces) and the indicator method 4 N HCl-insoluble ash). According to the indicator method the digestibility of crude nutrients was slightly high...
Cambridge H, Reynoldson JA, Dunsmore JD, Hilbert BJ.A radioimmunoassay for thromboxane B2 (TXB2) in unextracted horse plasma was evaluated. Sensitivity of the assay was 14.0 (SD 5.6) pg ml-1 of plasma. Interassay and intra-assay variation were 21.3 per cent and 4.3 per cent, respectively. The percentage of tracer bound in unextracted plasma in the absence of TXB2 was often higher than that in buffer. Therefore standard curves were obtained using standards diluted in plasma from horses treated with aspirin or in charcoal treated TXB2-free plasma. Standard curves determined in plasma and buffer were parallel. This assay was used to determine the ...
Kent JE.The concentrations of haptoglobin, immunoglobin (Ig)G(T) and IgG were measured in the serum of four previously parasite-free pony yearlings following a single dose of 700 (Group H) or 200 (Group L) stage three Strongylus vulgaris larvae (L3) and following a reinfection with the same doses 34 weeks later. The results are compared with an uninfected control pony. The haptoglobin concentration increased during Weeks 1 to 6 and 14 to 17 after infection in the serum of the ponies receiving 200 L3, but in only one pony dosed with 700 L3 (during Weeks 1 to 16). The serum haptoglobin also increased du...
Wilson DG, Peyton LC, Wolf G.Three horses with equine sarcoids were treated with radical surgical excision and immediate split-thickness skin grafts. Graft take ranged from 50 to 100%, and the epithelial coverage attained resulted in an early functional repair. In no instance was there a recurrence of the sarcoid.
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...
Nouws JF, Firth EC, Vree TB, Baakman M.Plasma disposition, protein binding, urinary recovery, and renal clearance of sulfamethazine (SMZ), sulfamerazine (SMR), and sulfadiazine (SDZ) and their N4-acetyl and hydroxy derivatives were studied in 4 horses in a crossover trial. The plasma concentration-time curves of the metabolites paralleled those of the parent drug in the elimination phase. Sulfamethazine and SMR were extensively metabolized. In plasma and urine, the main metabolite of the 3 sulfonamides tested was the 5-hydroxypyrimidine derivative, which was highly glucuronidated. Difference in elimination half-life of SMZ, SMR, an...
Watson ED, Stokes CR, David JS, Bourne FJ.The bactericidal and phagocytic activities of blood neutrophils suspended in uterine washings and the mobilization of neutrophils into the uterine lumen were studied in ovariectomized mares receiving oestradiol benzoate (N = 4), progesterone (N = 4) or oily vehicle (N = 4). Uterine lavage was performed sequentially up to 144 h after induction of endometritis by intrauterine infusion of glycogen (1%). There was no significant difference between the 3 groups in speed of mobilization of neutrophils into the uterus in the first 6 h after infusion but there were significantly more uterine luminal n...
Watson ED, Stokes CR, Bourne FJ.The function of blood and uterine luminal neutrophils from ovariectomized mares treated with ovarian steroids was investigated 18 h after intrauterine infusion of 1 X 10(9) Streptococcus zooepidemicus. Random migration of blood neutrophils under agarose was reduced by treatment with progesterone compared with that of neutrophils from oestradiol-treated and control mares. In-vitro addition of progesterone to blood neutrophils from acyclic ponies also reduced migration. Uterine neutrophils did not migrate under agarose which was probably an effect of bacterial phagocytosis. Hormone treatment had...
Harvey RC, Gleed RD, Matthews NS, Tyner CL, Erb HN, Short CE.Isoflurane was compared with halothane as an anesthetic agent for emergency colic surgery in a series of 38 juvenile and adult horses. After presurgical stabilization with fluids and supportive medications, anesthesia was induced by intravenous xylazine and/or diazepam followed by ketamine. Anesthesia was maintained with isoflurane or halothane in oxygen with controlled ventilation. Heart rates (HR), arterial blood gases, mean arterial pressures (MAP), rate pressure products (RPP), requirements for cardiovascular support medications, and recovery times to standing were compared using nonparame...
Kold SE, Hickman J, Meisen F.The quantitative aspects of equine cancellous bone graft incorporation and the possibility of influencing graft incorporation by daily exposure to a pulsed electromagnetic field (PEMF) was studied in eight yearling ponies. In order to be able to quantify formative aspects of graft remodelling, a double and treble tetracycline intravital labelling technique was used. Intravital radiographs were obtained at regular intervals throughout the trial, but were found to be of little assistance in assessing any differences between stimulated and non-stimulated grafts. The ponies were humanely destroyed...
Morier L, Cantelar N, Soler M.Eastern Equine Encephalitis (EEE) was in Cuba before the 1940s; the virus has been isolated from horses, birds, and rodents during epizootic as well as interepizootic periods. The only isolation of Western Equine Encephalitis (WEE) virus was from a sick pigeon found in the vicinity of Havana University. Both viruses can cause human disease; the isolation of WEE virus from the centre of an urban area emphasises the need for the prompt isolation and rapid identification of these agents. The object of this work was to compare the sensitivity of a continuous cell line (XL-2) from the toad, Xenopus...
Hellige M, Warnken T, Puff C, Feige K.An 8-year-old Warmblood gelding presented with a history of progressive ataxia for 6 weeks. Intra- and intervertebral ratios measured from lateral radiographs of the cervical spine were within normal limits. Computed tomographic myelography of the cervical spine revealed focal compression of the dorsal and the ventral contrast column as well as a ventral displacement of the spinal cord within the spinal canal due to a bulging of soft tissue attenuating material in the dorsal half of the intervertebral junction of C6 and C7. Post-mortem histopathological examination confirmed chondroid metapla...
Tulleners EP, Harrison IW, Raker CW.By use of endoscopy, 75 horses with respiratory noise and/or exercise intolerance were determined to have structural arytenoid cartilage abnormalities (60 primary, 11 after previous laryngeal surgery), or failed left laryngoplasty (4 horses) for laryngeal hemiplegia in which the arytenoid cartilage still appeared normal. Eighty-eight percent of the horses were either Thoroughbred (54 horses; 72%) or Standardbred (12 horses; 16%) racehorses; only 9 horses (12%) had occupations not related to racing. Seventy-six percent of the racehorses were 2 to 4 years old; all non-racehorses were greater tha...
Turner AS, White N, Ismay J.Thirty-five horses with a history of crib biting or wind sucking were treated with a modification of the Forssell procedure. The technique involved bilateral neurectomy of the ventral branch of the accessory nerve combined with excision of a portion of the omohyoideus, sternohyoideus, and sternothyroideus muscles. Twenty horses became free of the vice, while in 11 there was a noticeable reduction in frequency of the vice. Four horses returned to crib biting/wind sucking at the same intensity as before surgery. The observation time following each operation was at least 12 months. Complications ...
The Journal of heredityMarch 1, 1997
Volume 88, Issue 2 162-164 doi: 10.1093/oxfordjournals.jhered.a023079
Lear TL, Bailey E.The U2 linkage group of horses includes the genes albumin (ALB), vitamin D binding protein (GC), mitochondrial glutamate oxaloacetate transaminase 2 (GOT2), and haptoglobin (HP) which are found on two human chromosomes, namely, 4 (HSA 4) and 16 (HSA 16). Likewise these genes are also found on two different chromosomes in mice, rats, and cattle. Chromosome painting demonstrated that only horse chromosome 3 (ECA 3) hybridized with whole chromosome paints for both HSA 4 and HSA 16. This indicated that the equine U2 linkage group occurs on ECA 3, spanning the centromere. This technique will be use...
Vaughan LC.Local disorders of bone growth form an important group of the orthopaedic problems that occur in foals. The recognition of the condition presented is essential so that the appropriate corrective measures may be instituted, and an accurate prognostication made. A knowledge of the applied anatomy of the growth plate is essential to the understanding of these cases. Consideration is given to epiphyseal separation and to angular deformity, from the point of view of diagnosis, prognosis and treatment.
Taylor FG, Cooke BJ.The fragility of erythrocytes is easily demonstrated by their ability to withstand osmotic swelling and lysis in solutions of increasingly hypotonic saline. In healthy animals a plot of percentage haemolysis against increasing hypotonicity produces a sigmoid curve. Using the same data a derivative curve calculated from haemolytic increments shows a normal distribution of fragility within samples. In enhanced fragility due to immune-mediated haemolytic anaemia, these profiles of haemolysis are markedly altered and the derivative curve becomes multiphasic, indicating the presence of subpopulatio...
Hinchcliff KW, Sams RA.To determine the effect of administration of commercially available sodium bicarbonate (NaHCO3) on carbon 13 (13C) isotopic enrichment of carbon dioxide (CO2) in serum of horses. Methods: 7 healthy Thoroughbreds. Methods: Sodium bicarbonate (450 g) was administered via nasogastric intubation to horses. Horses had been fed a diet obtained from the same source and had access to water from the same source for 3 months before the study. Blood samples were collected immediately before and at 2, 4, 6, and 24 hours after administration of NaHCO3. The concentration of total CO2 in serum was measured b...
Picetti TS, Soveral LF, Miotto R, Erpen LMS, Kreutz Y, Guizzo JA, Frandoloso R, Kreutz LC.Immune-modulating molecules mainly act on innate immune cells, which are central to early defense against invading pathogens and contribute to developing adaptive immunity. Yeast-extracted β-glucan, a model immune-modulating molecule, is widely used in several animal species; however, its effect on horse immune parameters has not been thoroughly investigated yet. This study aimed to evaluate the effects of orally administered β-glucan on selected innate immune parameters in horses. Methods: Eighteen thoroughbred horses were assigned equally into three groups as follows: One control group (no...
Jean D, Lavoie JP, Nunez L, Lagacé A, Laverty S.A 6-year-old Thoroughbred mare had a 7-cm ulcerated mass on the cranial aspect of the left cervical area. Ultrasonography revealed the mass to be < 1 cm thick and composed of small lobules that were filled by material hypoechoic to the surrounding muscle tissues. Fine-needle aspiration of the mass yielded blood, and cytologic examination revealed a few epithelial cells with neoplastic changes. Thoracic radiography revealed an interstitial pattern with several disseminated nodules. A diagnosis of cutaneous hemangiosarcoma with pulmonary metastases was made. The diagnosis was confirmed at necrop...
Forhead AJ, French J, Ikin P, Fowler JN, Dobson H.Hyperinsulinaemia is a commonly-observed characteristic of insulin resistance, and a reduction in insulin sensitivity is thought to be either a causative and/or symptomatic feature of equine hyperlipaemia. A positive correlation (r = 0.545, P = 0.0015) existed between plasma insulin and triglyceride concentrations determined in 31 donkeys with naturally occurring hyperlipidaemia/hyperlipaemia. Greater insulin values tended to occur in the animals with an overweight body score. Inter-animal variation in insulin concentrations, however, prevented the identification of any differences either with...
Stewart M.The structure of vertebrate skeletal muscle is reviewed. The mechanism of muscular contraction and its control is then discussed from the point of view of molecular structure. Contraction takes place by a sliding filament mechanism produced by cross-bridges which form between thick and thin filaments. Control is exercised by tropomyosin and troponin. When the calcium concentration is low, these proteins interfere with the formation of cross-bridges and prevent contraction, but when the calcium concentration is increased, they no longer interfere and contraction proceeds.
Smith TR.A 2.5-month-old filly was presented with signs of esophageal obstruction. The filly was euthanized and postmortem examination revealed a vascular ring anomaly. The vascular ring anomaly was not caused by a persistent right aortic arch, which is the only vascular ring anomaly reported to occur in horses. Une pouliche de 2 1/2 mois a été présentée avec des signes d’obstruction œsophagienne. Après euthanasie, l’examen a révélé une malformation vasculaire annulaire. L’anomalie vasculaire annulaire n’était pas due à la persistance de l’arc aortique droit, seule malformation va...