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.
Brocard P, Pfister K.Between March 1988 and December 1989, 198 gastrointestinal tracts from slaughtered horses from different areas of Switzerland have been analysed for the presence and the frequency of Gasterophilus spp. During the same period--always between July and November--200 horses from selected areas of Western Switzerland have been checked for the presence of eggs and their subsequent developmental stages in order to investigate further clinical and biological aspects of this infection. The evaluation has been performed according to origin, age, sex, colour of the horse and seasonal pattern of the cases...
Santschi EM, LeBlanc MM, Weston PG.Plasma cortisol, oestrone sulphate and progestagens were measured in 22 stressed pregnant mares (gestation length 17-336 days) as indicators of fetal viability. Mares were bled every 12 h from time of admission, and plasma was stored at -70 degrees C until assayed. Four normal mares were bled twice weekly from Day 270 to parturition to provide baseline endocrine data. Cortisol and progestagen concentrations were measured by radioimmunoassay and oestrone sulphate was measured by enzyme immunoassay. Mares were grouped according to clinical diagnosis: surgical colic (Group 1, n = 11), medical col...
Weldon AD, Rowland PH, Rebhun WC.A 12-year-old Morgan gelding was examined for colic of 3 days duration. Signs of depression, colic, diarrhea, and endotoxemia persisted despite aggressive medical therapy and surgical exploration. Culture results from gastric fluid and feces yielded many colonies of Clostridium perfringens. This organism also was recovered from peritoneal fluid 10 days after admission; consequently, the horse was euthanized. At necropsy, a localized gas-filled, necrotic stomach wall was found; many mucosal and submucosal gas blebs were visible. Culture of this tissue yielded Clostridium perfringens. Emphysemat...
Urashima T, Saito T, Kimura T.1. Three neutral oligosaccharides were obtained from horse colostrum by ion-exchange, activated charcoal column and preparative paper chromatographies. 2. The following structures were elucidated by methanolysis, methylation analysis and 75 MHz 13C-NMR spectroscopy; Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc (HM-3a), Gal beta 1-4GlcNAc beta 1-6Gal beta 1-4Glc (HM-3b) and Gal beta 1-4GlcNAc beta 1-3[Gal beta 1-4GlcNAc beta 1-6]Gal beta 1-4Glc (HM-5). 3. HM-3a and HM-5 have been found in human milk, named as lacto-N-neotetraose and lacto-N-neohexaose, respectively. HM-3b has been isolated from g...
Hofferer S, Duchamp G, Palmer E.Twelve anoestrous mares were treated with an intravaginal sponge containing 0.5 g allyl trembolone (Regumate; Roussel UCLAF, Paris) and 50 mg oestradiol benzoate for 7 days, followed by daily intramuscular (i.m.) injections of 25 mg crude equine pituitary extract (CEG), with (n = 6) or without (n = 6) 0.25 mg porcine growth hormone (pGH). No difference in ovarian response to this superovulation treatment was observed between the 2 groups (2.2 +/- 0.4 vs 2.3 +/- 0.4 ovulations per mare, respectively). CEG treatment was then combined with allyl trembolone (40 mg per os per day) and prolonged in ...
Turner JE, Irvine CH.Gonadotrophin-releasing hormone (GnRH) was used in several regimens in anoestrous mares in an attempt to investigate the effects of frequency and dose on follicle-stimulating hormone (FSH) and luteinizing hormone (LH) release, and consequently on ovulation and corpus luteum establishment. Thrice daily injections of GnRH induced development of pre-ovulatory follicles, but hourly injections or constant infusions were required to induce ovulation. Hourly injections induced a much higher LH:FSH ratio in the presence or absence of ovarian hormones. When anoestrous mares were given an implant that r...
Shand N, Alexander SL, Irvine CH.For aqueous extracts of pituitary glands of oestrous mares, luteinizing hormone (LH) profiles were found to be similar to each other and to earlier work after chromatofocussing (CF) and isoelectricfocussing (IEF). After CF, both LH and follicle-stimulating hormone (FSH) in pituitary extracts focussed in multiple peaks in the acidic range, with 86% of LH and 80% of FSH found between pH 4 and 6. By contrast, in pituitary venous plasma, only 18% of the LH focussed in this range, whereas a significantly greater proportion (P less than 0.01) eluted above pH 7 than occurred in pituitary extracts (37...
Neuschaefer A, Bracher V, Allen WR.The effect of treating lactating mares with the dopamine agonist bromocriptine was investigated. Seven pony and 4 Thoroughbred lactating mares were given a single intramuscular (i.m.) injection of 100 mg bromocriptine between Days 18 and 28 after foaling when the secretion rate of prolactin was elevated. Prolactin and luteinizing hormone (LH) concentrations were measured in serial peripheral plasma samples taken before and after the treatment and, in 5 of the pony mares, levels of these hormones were also measured in pituitary venous effluent obtained by cannulation of the cavernous sinus. In ...
Lea RG, Bolton AE.Commercial preparations of equine chorionic gonadotrophin (eCG) and extracts of horse placenta taken at 80 days gestation were incorporated into mixed lymphocyte culture and mitogen stimulation assays of horse peripheral blood mononuclear cells. A dose-related inhibition of lymphocyte proliferation, indicative of immunosuppressive activity, was observed in both systems, both with commercial eCG preparations and tissue extracts. Negligible inhibitory activity was observed with an extract of term placenta. The inhibitory activity of the placental samples was not related to their eCG content as m...
Hierholzer JC, Stone YO, Broderson JR.Reference equine antisera to all 47 serotypes of human adenoviruses presently described have been prepared and evaluated by reciprocal neutralization and hemagglutination-inhibition tests. All tests were carried to endpoint dilutions a minimum of five times in each direction to give accurate values for homologous and heterologous antibody titers. Significant cross-reactions in the horse antisera were compared to similar data obtained from rabbit antisera. Using this analysis, major antigenic relationships exist among types 12-18-31 of subgenus A, types 7-11-14 and 34-35 of subgenus B, types 8-...
Fritsche A, Mathis GA, Althaus FR.Biotin deficiency in animals causes pathological changes of the skin and its appendages including, for example, exfoliative dermatitis, depigmentation, and alopecia. The hooves of biotin-deficient swine are weak, brittle, and often necrotic. These changes disappear after dietary biotin supplementation. Biotin supplementation also noticeably improves the hoof quality of horses, cattle and swine having no apparent biotin deficiency. In order to elucidate the molecular basis of these effects, the influence of biotin on cytokeratin expression in a keratinocyte cell line (Ha-CaT) was investigated u...
Kent JE, Goodall J.Serum haptoglobin was measured by immunoturbidity in Thoroughbreds stabled in three Newmarket yards for nine months. The mean serum haptoglobin value for horses housed in Stable 1 was 1.43 +/- 0.68 g/litre, similar to values in grazing adult ponies. The mean monthly haptoglobin values remained constant. For horses in Stable 2 there was an increase in serum haptoglobin values in June and July whereas, in Stable 3, the increases early in the training season were associated with an increase in serum viral titres. In equine serum, haptoglobin values estimated in g/litre by immunoturbidimetry were ...
Razumov IA, Agapov EV, Pereboev AV, Protopopova EV, Lebedeva SD, Loktev VB.A comparative study of the antigenic structure of virulent strains and attenuated vaccine strains of Venezuelan equine encephalomyelitis virus (VEEV) by means of monoclonal antibodies has made it possible to investigate the antigenic structure of the envelope glycoproteins E1 and E2, and to specify their role in the development of antiviral immunity. On the E1 glycoprotein there are five nonoverlapping antigenic sites consisting of eight epitopes that are recognized by monoclonal antibodies; six sites consisting of twenty epitopes were found on the E2 glycoprotein. The monoclonal antibodies ag...
Bhushan C, Müller I, Friedhoff KT.A rapid and simple method for concentrating leucocyte-free Babesia caballi-infected erythrocytes from in vitro cultures is described. Infected erythrocytes amounted to at least 95% of all red cells obtained.
Lepage OM, DesCôteaux L, Marcoux M, Tremblay A.The purpose of the study was to determine whether there were circadian variations in serum osteocalcin in normal horses and to determine whether it was important to regulate the time of blood sampling in clinical investigations. Osteocalcin or bone Gla-protein (BGP), alkaline phosphatase, total calcium, phosphate and total protein were studied over a 24 h period. Blood samples were taken every 60 min from nine adult Standardbred horses. There was a correlation between serum levels of alkaline phosphatase (r = 0.3, p less than 0.01), phosphate (r = 0.42, p less than 0.01) and serum osteocalcin ...
Morgan SJ, Stromberg PC, Storts RW, Sowa BA, Lay JC.Histological and morphometric evaluation of equine cranial mesenteric arteries was performed on 239 and 89 arteries, respectively. Histological examination revealed that thrombosis and the severity of inflammation varied on a seasonal basis and were directly associated with larval presence. Intimal and adventitial fibrosis were generally of greater severity than medial fibrosis. Fibrosis of the vasa vasorum was less frequent than fibrosis of the artery itself. Morphometry revealed a significant increase in intimal, adventitial and, to a lesser extent, medial area in affected as compared with n...
Page SW.The use of chloramphenicol in the horse is now prohibited as horses are classified as food-producing animals. However, chloramphenicol has until recently been widely available for oral, intramuscular or intravenous administration. A critical appraisal of the published literature on the use of chloramphenicol in the horse clearly demonstrates that there are sound pharmacokinetic and microbiological reasons for concluding that chloramphenicol is not an appropriate antibiotic for systemic use. The short half-life of chloramphenicol in the horse, together with the broad range of minimum inhibitory...
Boyle MS, Skidmore J, Zhang J, Cox JE.The effect of long-term treatment of stallions with a powerful gonadotrophin-releasing hormone (GnRH) analogue was investigated. In the first part of the study, 9 sexually mature pony stallions were allocated to 1 of 3 groups, each of which was treated with 240 micrograms or 60 micrograms Buserelin per day administered by subcutaneously sited osmotic pumps or 30-50 micrograms Buserelin per day via solid, slow-release implants injected subcutaneously. Peripheral blood plasma and serum samples were collected frequently and assayed for follicle-stimulating hormone (FSH) and luteinizing hormone (L...
Crawford WH, Houge JC, Neirby DT, Di Mino A, Di Mino AA.The effect of pulsed radio frequency therapy (PRFT) was evaluated on seven ponies with no arthritis and in 28 ponies in which arthritis was created using intra-articular amphotericin B to induce synovitis in the right middle carpal joint. The ponies were divided into five treatment and two control groups. Two levels of arthritis were created and two dosage levels of PRFT were evaluated. The effect of PRFT on arthritic and nonarthritic joints was measured by comparing synovial fluid parameters, the degree and duration of lameness, the range of carpal motion, and carpus circumference, for treate...
Ueda H, Abe M, Takehana K, Iwasa K, Hiraga T.The innervation of the red pulp in the spleen of horse and pig was investigated by electron microscopy. In addition, the neurilemma was studied by immunohistochemistry specific for S-100 protein. In the pig, a large population of smooth-muscle cells extending from the smooth-muscle trabeculae was present in the red pulp. The cytoplasmic processes of reticular cells enwrapped the smooth-muscle cells, and nerve fibres were distributed between the smooth-muscle cells and the reticular cells. The nerve terminals clustered toward the facing of the smooth-muscle cells. Nerve fibres and terminals wer...
Hamon M, Clarke SW, Houghton E, Fowden AL, Silver M, Rossdale PD, Ousey JC, Heap RB.Changes in the progesterone metabolite 5 alpha-dihydroprogesterone (5 alpha-DHP) in maternal plasma in late gestation, and possible sites of production of this steroid were studied in pony and Thoroughbred mares by an enzyme-linked immunosorbant assay for 5 alpha-DHP. In Thoroughbred mares, plasma 5 alpha-DHP increased from 63.7 +/- 10.5 ng/ml (27 days pre-partum) to 161.7 +/- 30.8 ng/ml (1 day pre-partum) falling to 90.2 +/- 16.1 ng/ml on the day of parturition. In pony mares, values rose from 30.8 +/- 8.1 ng/ml (27 days pre-partum) to 79.1 +/- 30.8 ng/ml (3 days pre-partum) and then decrease...
Cocco MJ, Lecomte JT.A proton nuclear magnetic resonance spectroscopic study of horse apomyoglobin was undertaken in order to define the regions of myoglobin that are and that are not structurally affected by the binding of the prosthetic group. It was found that, in spite of the poor spectral resolution, a number of spin systems could be identified by using standard correlated methods. Four clusters consisting mostly of hydrophobic residues were detected by nuclear Overhauser spectroscopy, two of which involved the tryptophan side chains. Extensive similarities to nuclear Overhauser spectroscopy data collected on...
Merkens HW.Forces occurring between the hoof and the ground during the stance phase (i.e. the ground reaction forces GRF) can be analysed using a force plate. The average of a number of five to stance time and body weight normalised GRF recordings (data) will provide 'representative' GRF patterns. These can be used for objective and quantitative evaluation of various forms of therapy in equine orthopaedics as well as for locomotion research during various forms of equestrian sports.
Murray MJ.Hypothyroidism was diagnosed in a neonatal Thoroughbred foal that was weak, hypothermic, and septicemic. Administration of thyroid-releasing hormone elicited attenuated increases in concentrations of free and total triiodothyronine and thyroxine, as compared with a clinically normal, age-matched foal. The foal died of apparent respiratory insufficiency, pre- and postmortem findings compatible with hypothyroidism included hypothermia, large thyroid glands with distended, colloid-filled follicles, and severe, diffuse atelectasis, with thickened alveolar septae and degenerating alveolar squamous ...
McCarty JE, Trim CM, Ferguson D.On 74 occasions, 54 horses and 6 foals were anesthetized with xylazine and ketamine or xylazine, guaifenesin, and ketamine, with or without butorphanol. On 64 occasions, anesthesia was prolonged for up to 70 minutes (34 +/- 15 min) by administration of 1 to 9 supplemental IV injections of xylazine and ketamine at approximately a third the initial dosage. All horses except 5 were positioned in lateral recumbency, and oxygen was insufflated. In adult horses, the time from induction of anesthesia to the first supplemental xylazine and ketamine injection was 13 +/- 4 minutes and the time between s...
Németh F.The aetiology and pathogenesis of navicular bone disease and sesamoidosis are discussed on the basis of findings reported in the literature and research. A marked similarity is found to be present between the clinical presentation, aetiology and pathogenesis of these two diseases. In addition, the intra and juxta-articular signs of degeneration as seen in these diseases are similar to those seen in various forms of arthrosis. Circulatory disturbances resulting from partial or complete arterial occlusion, caused by arteriosclerosis, are likely to play an important role in the cause of degenerat...
Gallacher K, Santos LC, Campoy L, Bezuidenhout AJ, Gilbert RO.The aim of this study was to develop and evaluate a procedure for equine pudendal nerve block using a peripheral nerve locator. In the first experiment, six ponies were used to determine the relationship between elicited muscle contractions (anal, perineal or both) and nerves serving the perineal region (pudendal, caudorectal and perineal nerves) when methylene blue dye was injected using the electrolocation technique. This experiment showed that the pudendal nerve was approached effectively when both anal and perineal twitch were elicited during electrolocation. In a second experiment, seven ...
Easter JL, Schumacher J, Watkins JP.Surgical arthrodesis of the distal interphalangeal (DIP) joint by transfixation casting was used to salvage a three-year-old filly and a yearling filly that were chronically lame because of infection of the DIP joint for breeding. Unlike previously described techniques for arthrodesis of the DIP joint, the technique used did not require insertion of implants across the joint, which may have contributed to the successful outcome.
Pick M.After a brief introduction to the most important aspects of the current sport of horse-racing the equipment and tack will be described with respect to the horses wellbeing: bridles, tonguestrap, blinkers, saddle and girth. With reference to incorrect equipment for the rider, the wip and its misuse will be discussed. Problems with saddling and at the starting gate are often indicators of the incorrect application of aids. Then the misuse of the automatic horse trainer, treadmills and swimmingpools will be explained. Finally, the three most important requirements for improving the protection of ...
Manneveau GB, Robert MP, Tessier C, Bizon-Mercier C.This report describes a rare case of gastric impaction caused by a trichophytobezoar in a foal. This case highlights the difficulty in diagnosing this condition and reports surgical removal via a gastrotomy after failure of medical treatment. Ablation chirurgicale d’un trichophytobézoar gastrique chez un poulain. Ce rapport décrit un rare cas d’obstruction gastrique causé par un trichophytobézoar chez un poulain. Ce cas souligne la difficulté à diagnostiquer cette affection et fait rapport sur l’ablation chirurgicale lors d’une gastrotomie après l’échec du traitement médical...
Leadon DP, Rossdale PD, Jeffcott LB, Allen WR.Various regimens of prostaglandins, alone or followed by oxytocin, were given to induce parturition in mares during the pre-viable and premature periods of gestation and in near-term mares. The most successful method of induction was found to be 2 i.m. injections of 500 micrograms fluprostenol (Equimate: I.C.I.) at a 2-h interval followed (if necessary) by 10-20 i.u. oxytocin injected i.v. in 5 i.u. serial increments every 15-20 min. Peak concentrations of the prostaglandin metabolite (PGFM) in response to the inducing agents were shown to be associated with delivery at, but not before, 320 da...
Yarnell K, Walker SL.Assessment of faecal glucocorticoid metabolites (FGM) offers a noninvasive method of monitoring adrenal activity in domestic horses. Samples are collected on an opportunistic basis and, if they are not fresh or have been exposed to the elements before they are identified, may not accurately reflect FGM concentrations. Objective: To explore the impact of a range of environmental conditions upon the integrity of FGM levels in equine faeces. Methods: In vitro experiment. Methods: Equine faeces were exposed to six controlled environmental conditions intended to simulate a range of weather and seas...
Maddison JE.Fifty-nine reports of suspected adverse drug reactions (ADRs) were received by the Adverse Drug Reaction Subcommittee of the Australian Veterinary Association from April 1992-March 1993 inclusive. The number of reports received/number of animals involved per species was: dogs (30/43); cats (11/14); horses (8/10); cattle (9/30); ferret (1/1). Of these, 37 (63%) were classified as definite ADRs and 12 (20%) as probable ADRs. In 10 (17%) reports an ADR could not be substantiated or there was insufficient information available to make a decision. Twenty-three reports involved apparent hypersensiti...
Trostle SS, Markel MD.Incarceration of the large colon through a rent in the gastrosplenic ligament of a horse was surgically corrected via ventral midline celiotomy. Clinical signs were similar to those in other horses with nonstrangulating large colon disorders. Diagnosis of large colon incarceration in the gastrosplenic ligament was determined by surgical abdominal exploration. The findings of medial deviation of the spleen, location of the large colon lateral to the stomach and caudolateral to the spleen, and caudocraniad passage of the large colon through the gastrosplenic ligament are similar to findings in h...
Rooney JR.An hypothesis on the pathogenesis of curb in horses is considered in the light of conformation, work and the appropriate mechanics. Prevention consists of graded work until the planter tarsal ligament has strengthened sufficiently to withstand maximum normal forces.
Mc Nally TP, Slone DE, Lynch TM, Hughes FE.To validate the safety of a suprapatellar pouch (SPP), approach to the femoropatellar joint (FPJ), and describe use of a laparoscopic cannula to remove debris or loose bodies. Methods: Retrospective case series Methods: Horses (n = 168) with osteochondritis dissecans (OCD) of the FPJ. Methods: Arthroscopy was performed on 245 FPJ with OCD. Two subpatellar portals were created, 1 axial and 1 abaxial to the lateral patellar ligament. Additionally, a SPP egress portal for lavage, was created 2 cm proximal to the most palpable dorsolateral eminence of the patellar base. A 10-mm laparoscopic cannul...
Sonmez K, Gurel A, Takai S.The aim of the present study was to develop an immunocytochemical procedure for the early detection and demonstration of Rhodococcus equi in smears of tracheal aspirates taken from live foals in field conditions. Tracheal wash samples were collected from thoroughbred foals, aged 1-5 months and located in studs around Bursa and Istanbul, Turkey. Some foals were suspected of having R. equi infection on the basis of clinical examination (n=56) and others were unaffected control animals (n=54). Serum samples were also collected from each foal for testing for the presence of R. equi-specific antibo...
Meehan LJ, Taylor SE, Labens R, Cillán-García E.Assessment of the usefulness of magnetic resonance imaging (MRI) in treatment planning in suspected cases of quittor in the horse. Methods: Five horses with chronic discharging tracts at the level of the foot underwent MRI for treatment planning. Results: The MRI examination revealed variable involvement of soft tissue and osseous structures of the foot in addition to abnormalities of the ungular cartilages in all cases. In two cases, follow-up MRI examination was performed. Four of five horses had a successful outcome, with three of these undergoing only one surgical procedure and one being m...
Lindner A, Wahdati A, Sommer H.GSH-Px activity in blood and plasma of 269 horses was determined and interrelated to age, sex, and type of use or breed. Furthermore values in blood were related to hematocrit and hemoglobin contents. Trotters and riding horses had higher GSH-Px activities in plasma as well as in blood (0.83 +/- 0.22 and 0.79 +/- 0.23 U/ml plasma or 27.2 +/- 4.3 and 24.0 +/- 7.0 U/ml blood) than Thoroughbreds in training and yearlings (0.61 +/- 0.,14 and 0.56 +/- 0.16 U/ml plasma or 20.6 2 +/- 6.9 and 24.6 +/- 4.3 U/ml blood). 3 to 6 years old Thoroughbreds had higher GSH-Px-activities than 1 to 2 years old on...
Malalana F, Ireland JL, Pinchbeck GL, McGowan CM.Risk factors for a first episode of primary uveitis in horses have not been determined. In addition, disease progression and the proportion of horses that develop recurrence following the original episode are not known. Objective: To determine the risk factors for the development of a first episode of primary uveitis in horses in the UK and to document the proportion of cases that experience recurrence following this first episode. Methods: Prospective case-control longitudinal study. Methods: Horses with a first episode of primary uveitis between July 2014 and August 2018 were recruited to th...