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.
Auer DE, Ng JC, Thompson HL, Inglis S, Seawright AA.An acute phase reaction was elicited in four horses to which Freund's adjuvant was administered intramuscularly. The localised inflammation was accompanied by changes in the plasma concentrations of copper, iron and zinc. The plasma copper concentration, the plasma ceruloplasmin copper concentration and the ceruloplasmin oxidase activity in the plasma steadily increased to a maximum 24 days after the administration of the adjuvant. At this time, the plasma copper concentration was 2.2 micrograms/ml, a 90 per cent increase over the baseline concentration. The ratio of the concentration of plasm...
Haluska GJ, Wilkins K.Rectal temperature was recorded from 22 mares at 0700, 1500 and 2300 h daily for seven days pre-partum and one day post partum. A circadian variation in rectal temperature was present with the lowest temperature recorded at 0700 h. Because of this, the mares were divided into three groups based on time of parturition; those foaling between 0700 and 1500 h (n = 2); between 1500 and 2300 h (n = 13); and between 2300 and 0700 h (n = 7). On the day prior to delivery (Day -1) the circadian pattern was absent because the nocturnal increase did not occur. A significant decrease in temperature was rec...
Bülow A, Bülow T, Mill J, Dietz O.Painful interventions can be performed on horse in standing position by means of sedative analgesia, also called standing-position anaesthesia. Combinations of anaesthetics are quite often used, in that context, for the purpose of producing analgetic effects stronger and more reliable than those that would be obtainable from one anaesthetic alone. The following combinations were comparatively tested for their analgetic and sedative effects and their effects upon the organism: Chloralhydrate with Ursonarkon (oxazolidone), Chloralhydrate with Rompun (xylazine), Chloralhydrate with morphine hydro...
Beard WL, Robertson JT, Getzy DM.To compare the effects of placing enterotomy incisions on or off the antimesenteric teniae and closing the intestinal mucosa as a separate layer, four longitudinal enterotomies were performed in the descending colon of each of six horses by the following techniques: incision through the antimesenteric teniae with one- and two-layer closure, and incision adjacent to the teniae with one- and two-layer closure. The horses were necropsied at day 33 for evidence of obstruction, adhesions, and ultrasonographic determination of the percent reduction in lumen diameter. Histologic and histomorphometric...
DeBenedette V.Horseback riding carries several risks, some of which can be minimized if riders take riding lessons, wear proper headgear and footgear, and remember that they are on top of a large, willful animal.
Beard WL, Lohse CL, Robertson JT.The blood supply to the descending colon of the horse was studied by gross dissection and methyl methacrylate corrosion casts. The arterial supply is derived from the left colic artery and cranial rectal artery with the left colic artery supplying approximately the proximal three fourths. Each artery gives off four to eight arcuate arteries that form a series of anastomosing arcades. The arcade pattern continues to form a marginal artery that parallels the long axis of the colon. Small branches from the marginal artery anastomose with adjacent branches to form a secondary arcade. The secondary...
Clay CM, Squires EL, Amann RP, Nett TM.Effects of season and photoperiod on the anterior pituitary gland and testes were studied by responses to exogenous GnRH. Stallions were assigned to one of three treatments: 1) control, exposed to natural day length; 2) S-L, 8 h of light and 16 h dark (8:16) for 20 wk beginning July 16, 1982 then 16:8 from December 2, 1982 until March 5, 1984; or 3) S-S, 8:16 from July 16, 1982 until March 5, 1984. Approximately every 8 wk, stallions were administered GnRH (2 micrograms/kg BW) and blood was sampled at 20-min intervals for 2 h before and 8 h after GnRH administration. Concentrations of LH, FSH ...
Guthrie AJ, Nichas E, Viljoen FV, Hartmann AM, Killeen VM.A case of sustained supraventricular tachycardia of unknown aetiology in a two-year-old Thoroughbred filly is reported. The cardiac dysrhythm was successfully treated by the oral administration of quinidine sulphate. Conversion of the dysrhythm to sinus rhythm occurred approximately 80 min after the initial dose of 5 g of quinidine sulphate. The horse returned to training approximately 2 months after treatment and has since successfully returned to racing.
Wheeler SJ, Plummer JM.Transverse sections of the lateral palmar nerve from a group of horses free from neuromuscular disease were assessed quantitatively, with emphasis on differences in the fibre population related to age. Morphometric analysis of the population of myelinated and unmyelinated fibres was performed. Changes were identified, there being a loss of larger myelinated fibres in older horses. The relationship of myelin thickness to axon diameter and the unmyelinated fibre population did not alter with age. The lateral palmar nerve is suitable for biopsy and electrophysiological study in the horse, but age...
Morris DD, Ward MV, Whitlock RH.Plasma concentrations of plasminogen were determined in 28 clinically normal horses, including 13 adult geldings, five non-pregnant mares, five pregnant mares and five yearlings (two fillies, three geldings). Plasminogen was quantitated by a chromogenic assay based on activation of plasmin by excess urokinase. The overall mean plasma plasminogen for these horses was 2.94 +/- 0.54 CTA units (casein units, as defined by the Committee on Thrombolytic Agents) per ml. There were no significant differences in mean plasma plasminogen values among adult geldings, non-pregnant mares, pregnant mares or ...
Salonen JS, Vähä-Vahe T, Vainio O, Vakkuri O.The pharmacokinetics of detomidine, a novel analgesic sedative, was studied in the major target species after high (80 micrograms/kg) i.v. and i.m. doses. In addition, drug residues in some organs were determined. Concentrations were measured using a sensitive, detomidine-specific radio-immunoassay method. Rapid absorption following i.m. dosing occurred. Absorption half-lives were 0.15 h (horse) and 0.08 h (cattle). The mean peak concentration in the horse (51.3 ng/ml) was achieved in 0.5 h and in the cow (65.8 ng/ml) in 0.26 h. The areas under the concentration curve after i.m. dosing were 66...
Lindsay WA, Robinson GM, Brunson DB, Majors LJ.Wick catheters were used to measure intracompartmental pressures of the extensor carpi radialis muscles and long heads of the triceps brachii muscles of 7 horses maintained under halothane anesthesia during controlled ventilation. Horses were positioned in left lateral recumbency on a water bed for 4 hours. Using a crossover design, 6 of the 7 horses were subjected to normotensive and hypotensive anesthesia on separate occasions. Hypotension was achieved by increasing the inspired halothane concentration. Hematologic and biochemical measurements were determined at designated intervals before, ...
Zwain I, Gaillard JL, Dintinger T, Silberzahn P.A single i.m. injection of testosterone (750 mg of testosterone bexahydrobenzoate) or i.v. injection of human chorionic gonadotrophin (hCG) (10,000 IU) was given to geldings and stallions. Levels of unconjugated and conjugated (after solvolysis) androgens and estrogens were measured in blood and urine samples taken daily from the day of injection (D0) to the tenth day post-injection (D10). In the stallion, both treatments resulted in a sharp increase of plasma estrogens, which peaked one day before the androgen levels. Our results confirmed the testicular localization of a potent aromatase, wh...
Delbeke FT, Debackere M.The prototype of a commercial ELISA test kit designed for fentanyl determination in human urine has been evaluated for screening fentanyl in horse urine and plasma. The measurement of fentanyl after intravenous (2 mg) and intramuscular (0.25 mg) administration in undiluted plasma was not reproducible while accurate quantification of fentanyl in urine greatly depends on the composition of the horse urine. The ELISA assay, however, is simple and could be successfully used for quantitative measurements in diluted urine and for rapid qualitative screening for fentanyl in large numbers of urine sam...
Pace-Owens S.Gamete intrafallopian transfer (GIFT), developed in 1984, was the result of further studies on in vitro fertilization (IVF). Since that time many nurses have worked in settings near in vitro fertilization centers and, therefore, have a basic understanding of the technology. An overview is given of the GIFT procedure to prepare nurses to advise and refer couples who may qualify for GIFT and to highlight the shift in the fertility program nurse coordinator's functions toward the positions of administrator and consultant.
Pascoe DR, Stover SM.A surgical technique for removal of one conceptus from mares with twin concepti more than 35 days of gestational age was evaluated. One conceptus was removed surgically from each of 15 mares carrying twin concepti that were 41 to 65 days of gestational age. As determined by ultrasonography, eight mares had bicornuate and seven mares had unicornuate twin concepti. For maintenance of pregnancy if surgical trauma should cause prostaglandin release and luteolysis, progesterone was administered prophylactically. Flunixin meglumine was administered perioperatively to minimize prostaglandin release. ...
Ford TS, Ross MW, Orsini PG.Three techniques for inducing analgesia of the proximal metacarpal region were evaluated for the frequency of inadvertent injection into the middle carpal and carpometacarpal joints. Using methylene blue solution as a marker dye and 30 fresh cadaver specimens each, three clinicians performed either 30 infiltrations at the origin of the suspensory ligament (method A), 30 palmar and palmar metacarpal nerve blocks at the proximal end of the metacarpus (method B), or 30 palmar and palmar metacarpal nerve blocks at the distal aspect of the accessory carpal bone (method C). The frequency of inadvert...
Beadle RE, Short CR, Corstvet RE, Pawlusiow J, Nobles DD, McClure JR, Guthrie AJ, Clarke CR.A soft-tissue infection model was created in eight horses by infecting subcutaneous tissue chambers with Streptococcus zooepidemicus organisms. Responses of the horses to the infections were determined by monitoring changes in the complete blood count and body temperature and by following changes in the cytology and protein content of the tissue chambers. Systemic reactions to the infections included a mild neutrophilia, mild pyrexia and mild anemia. There was a marked influx of neutrophils and protein into the chambers after they were seeded with bacteria and chamber neutrophil viability decr...
Young SS, Hall LW.Total respiratory impedance was measured rapidly and noninvasively in conscious horses over the frequency range 3 to 40 Hz by the forced random noise method. The shape of curve of impedance versus frequency in horses was markedly different from that of humans. Respiratory resistance was readily found as the real part of impedence and both its absolute value and frequency dependence are useful indices of pulmonary function. It was difficult to obtain meaningful results in intubated animals with the method because of the mechanical properties of the endotracheal tube itself.
Arden WA, Stick JA, Parks AH, Chou CC, Slocombe RF.Physiologic effects of 1 hour of ischemia and 1 hour of reperfusion on equine jejunum and protective effects of systemic administration of dimethyl sulfoxide (DMSO, 1 g/kg of body weight) were investigated in 18 ponies, using neurally intact segments of jejunum perfused at constant flow with heparinized blood. Ponies were allotted to 4 groups: group 1, saline solution administered (control, n = 3); group 2, DMSO administered (DMSO, n = 3); group 3, ischemia induced and saline solution administered (ischemia, n = 6); and group 4, ischemia induced and DMSO administered (ischemia-DMSO, n = 6). In...
Attenburrow DP, Portergill MJ, Vennart W.A nuclear medicine facility constructed specifically for the application of a gamma camera system to the radioisotope imaging of bone, pulmonary circulation and ventilation in the horse is described. The gamma camera was previously used for human nuclear medicine, and a support for the gamma camera head was specifically designed for this work. Imaging protocols are suggested and the necessary materials for bone and lung studies are described. Images of bone and lung are shown and computer analysis of the data indicated. Imaging times are approximately 1 to 2 mins and typical bone and lung stud...
Wilson DA, Foreman JH, Boero MJ, Didier PJ, Lerner DJ.A large granulosa cell tumor was believed to be responsible for causing obstruction and subsequent rupture of the small colon in a 10-year-old Quarter Horse mare. Two months earlier, a mass, tentatively diagnosed as granulosa cell tumor of the left ovary, had been identified by means of rectal palpation and ultrasonography. The mare was evaluated for clinical signs of acute, severe, abdominal pain, increased heart rate, cyanotic mucous membranes, clinical dehydration, with high PCV, leukopenia, and extreme abdominal distension. A large soft tissue mass and taut band that constricted the lumen ...
Firth EC, Whittem T, Nouws JF.Six adult ponies were injected in the same intramuscular site with kanamycin sulphate (10 mg/kg). Two hours later, arthrocenteses of the right metacarpophalangeal, radio-carpal, intercarpal, tibio-tarsal and metatarsophalangeal joints were performed within 3 minutes. Arthrocenteses of the same joints on the left side were conducted 5 hours later. When expressed as a percentage of plasma drug concentration, differences in synovial fluid drug concentration between the joints sampled at 2 and 5 hours after injection were not detected.
Simon F, Laczay P, Móra Z, Lehel J.The target animal safety of a dexamethasone-prednisolone combination was studied on 12 horses divided into two groups of six each. One group of horses received the therapeutic dose of the combination (25 mg/animal dexamethasone pivalate and 75 mg/animal prednisolone) and the second group was given the threefold dose of it. The preparation was administered intravenously for 2 consecutive days. For assessment of safety a wide range of clinical, haematological, biochemical and urine variables were tested as laid down in the guidelines of the FDA. All horses treated by the therapeutic or the three...
Magnuson N, Perryman L, Wyatt C, Mason P.Severe combined immunodeficiency (SCID) occurs in horses of the Arabian breed and is inherited as an autosomal recessive trait1. Affected foals are severely lymphopenic with an absence of functional B and T lymphocytes.2 The few lymphocytes that can be found in affected foals resemble large granular lymphocytes (LGL) and can be grown long-term with media containing interleukin-2 (IL-2).3 The disorder is restricted to the lymphoid system, as other leukocytes are functionally and quantitatively normal.4
Gomaa N, Elemiri M, Hegazy Y, Zeineldin M, Nassif M, Alcala-Canto Y, Barbabosa-Pliego A, Rivas-Caceres RR, Abdelmegeid M.A retrospective cohort study was conducted on two Egyptian horse farms with most of horses were suffered from abdominal pain to describe the associations between the occurrence of mycotoxicosis and equine colic. The farms owner complain was an unexpected increase in number of colic cases and deaths among horses. The association between colic and risk factors (sex, type of food either dry or mixed with roughages and hematobiochemical parameters) was compared using independent sample T-test. The associations between possible prognostic indicators for colic caused by mycotoxicosis was estimated u...
Sharma AK, Singh TP.Lactoferrin binds two Fe(3+) and two CO(2-)(3) ions with high affinity. It can also bind other metal ions and anions. In order to determine the perturbations in the environments of the binding sites in the N and C lobes and elsewhere in the protein, the crystal structure of oxalate-substituted diferric mare lactoferrin has been determined at 2.7 A resolution. The final model has a crystallographic R factor of 21.3% for all data in the resolution range 17.0-2.7 A. The substitution of an oxalate anion does not perturb the overall structure of the protein, but produces several significant changes...
Freeman DE, Kilgallon EG.To determine if venous strangulation obstruction (VSO) of the distal half of the equine small intestine would increase length of that segment. Methods: Halothane-anesthetized horses were assigned randomly to 3 groups of 5 horses: Group 1 (controls)--the entire small intestine was measured and rubber-shod clamps were applied to mark each end of the most distal 50% of the small intestine; Group 2--same procedure, except that VSO was induced in the distal 50% of the small intestine for 180 minutes; and Group 3--same initial procedure, except that VSO was induced for 90 minutes and followed by rep...
Baker SJ, Gerring EL.Impedance epigastrography was used to measure gastric emptying rates on two occasions in each of three foals. After smoothing of the raw data, emptying of water appeared to obey an exponential model. The mean emptying rate constant (SEM) was 0.171 +/- 0.038 min-1 (mean emptying half time 4.9 +/- 1.0 min).
Menozzi A, Pozzoli C, Poli E, Delvescovo B, Serventi P, Bertini S.We investigated the effects of nonselective muscarinic antagonist (atropine) and of selective muscarinic subtype 1 (M1), 2 (M2), 3 (M3) antagonists (VU0255035, methoctramine, pFHHSiD, respectively) on the contractions evoked by electrical field stimulation (EFS) or by exogenous ACh in isolated horse bronchial muscle. Atropine completely inhibited neurogenic contractions in a concentration-dependent fashion, whereas selective muscarinic antagonists induced relevant modifications only at the highest concentration tested. Experiments with selective muscarinic antagonists in combination showed tha...
Knych HK, McKemie DS, Yim S, Stanley SD, Arthur RM.Given the potential for long-term inhibition of bone remodeling/healing and detrimental effects to horses in training, bisphosphonates are tightly regulated in horseracing. Hair has proven to be an effective matrix for detection of drug administration to horses and has been particularly effective in detecting drugs for a long period of time post administration. Thus, hair may prove to be a useful matrix for detection of administration of this class of drugs. The objective of the current study was to develop an assay and assess the usefulness of hair as a matrix for long-term detection of clodr...
Bauer B, Blank J, Heile C, Schein E, Clausen PH.A fence of black mosquito netting of 100 cm height, pre-treated with 80 mg/m2 of deltamethrin and UV-protected, was used to shelter horses from nuisance and biting insects on pasture in northern Brandenburg. The netting material was attached to the surrounding poles of the existing fences at a height of 15 cm above ground. Three trial groups were selected grazing in spatially separated areas with comparable densities of insect populations. One paddock was completely fenced apart from a wall of 170 cm height and 70 m length. The second pasture had only partial protection with 126 m (13.4%) of f...
Attenburrow DP, Goss VA.A case of acute destabilization of the right stifle joint associated with rupture of the anterior cruciate ligament and avulsion fracture of the tibial spine in a horse is reported. The diagnosis was obtained by scintigraphy and radiography. Post mortem investigations 6 weeks after injury demonstrated fibrillation of surface cartilage in regions unprotected by tibial menisci. No pathological change was demonstrated in the subchondral bone of the tibia in regions associated with loss of cartilage integrity.
Leifsson PS, Olsen SN, Larsen S.This paper is the first report of systemic tuberculosis involving the eyes in a horse. The animal lost condition and gradually became increasingly blind in both eyes; it was eventually euthanased. The pathological findings included bilateral, mycobacterial granulomatous uveitis with unilateral retinal detachment and necrosis, and disseminated, mycobacterial granulomatous foci in the myocardium, lungs, bronchial lymph nodes, kidneys, liver, pancreas, colon and visceral serosal surfaces, with the most extensive lesions in the myocardium. The mycobacteria were identified as Mycobacterium avium.