Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Wensvoort P, Steenbergen-Botterweg WA.When adipose tissues of horses and ponies affected with generalized steatitis were extracted by acetone, methanol and chloroform, non-extractable lipids were found to be present, which had become insoluble as a result of peroxidation and polymerization and had acquired autofluorescent characteristics. The origin of these lipids varies. Peroxidation occurs in three different lipid compartments, namely in the cytoplasm of the necrotized adipose cells, in the macrophagess and in the fat globules present in stroma.
Allen WR, Stewart F, Cooper MJ, Crowhurst RC, Simpson DJ, McEnery RJ, Greenwood RE, Rossdale PD, Ricketts SW.This research investigates the use of synthetic prostaglandin analogues, specifically ICI-81008 and ICI-79939, in mares for inducing luteolysis, the regression of the corpus luteum, to manage infertility issues. The study […]
Akbari Shahkhosravi N, Kakavand R, Davies HMS, Komeili A.The health and performance of horses are significantly affected by diseases associated with the hoof. Laminitis is a critical hoof disease that causes pain and, potentially, severe hoof and bone pathology. Objective: To generate an equine hoof finite element (FE) model to investigate the impact of normal and toe-in hoof conformations on the degeneration (decrease in elastic modulus) of the laminar junction (LJ), as occurs in chronic laminitis. Methods: Computer software modelling. Methods: A hoof FE model was generated to investigate the biomechanics of hoof laminitis. A 3D model, consisting o...
Gordon BJ, Latimer KS, Murray CM, Moore JN.Continuous-flow centrifugation leukapheresis techniques were used to collect 300-ml volumes of leukocyte-rich plasma from 5 nonmedicated horses and from 5 corticosteroid-stimulated horses. White blood cell counts and differential counts were performed on the horses before (base line) and up to 48 hours after leukapheresis. Systemic administration of hydrocortisone increased numbers of total WBC and neutrophils and improved harvest of these cells. Nonmedicated horses had a mean yield of 3.38 X 10(10) leukocytes in the 300-ml volume. Stimulated horses yielded a mean of 6.88 X 10(10) leukocytes. ...
Echeverria KO, Lascola KM, Giguère S, Foreman JH.Minocycline is commonly used to treat bacterial and rickettsial infections in adult horses but limited information exists regarding the impact of feeding on its oral bioavailability. This study's objective was to compare the pharmacokinetics of minocycline after administration of a single oral dose in horses with feed withheld and with feed provided at the time of drug administration. Six healthy adult horses were administered intravenous (2.2 mg/kg) and oral minocycline (4 mg/kg) with access to hay at the time of oral drug administration (fed) and with access to hay delayed for 2 hr after ...
Gilhooly MH, Eades SC, Stokes AM, Moore RM.To measure and compare palmar digital venous plasma nitric oxide (NO) concentrations and digital arterial blood flow after application of topical nitroglycerine (NTG). Methods: Experimental study. Methods: Healthy adult horses (n=8). Methods: Digital blood flow was measured by an ultrasonic Doppler flow probe surgically implanted around the medial palmar digital artery. Blood was collected from a catheter placed in the medial palmar digital vein for quantification of NO. NTG patches, NTG ointment or control patches were placed over the palmar digital vessels at the level of the fetlock. Two ho...
Gehlen H, Groner U, Rohn K, Stadler P.In the present study, a right heart catheterisation was carried out on three consecutive days in 17 healthy horses to evaluate the day-to-day variability of cardiac pressure values. Cardiac pressure values were measured in the right atrium, the right ventricle, the pulmonary artery, and the pulmonary capillaries (pulmonary artery wedge pressure). Additionally it was examined wether the cardiac pressure variability was influenced by the heart rate and if there are differences between trained and untrained horses. Beside the coefficient of variances, statistical analysis with assessment of varia...
Wijnberg ID, van der Kolk JH, van Garderen E, Binkhorst GJ.A 18-year-old Dutch Warmblood mare was referred for colic. Upon arrival, lethargy, blindness, head pressing, ataxia, and circling were the main clinical signs. On rectal examination a hard mass and oedema around the cranial mesenteric artery were palpated. Plasma liver enzyme activities and the ammonia level were elevated. Atrial fibrillation with a pulse frequency of 36-52 beats per minute was noticed. On both sides a holosystolic murmer with the maximum intensity on the right side could be auscultated. Postmortem examination revealed eccentric hypertrophy of the right atrium and a pale spott...
Brown-Douglas CG, Firth EC, Parkinson TJ, Fennessy PF.To determine the responsiveness of the pituitary-gonadal axis of peri-pubertal colts to GnRH, buserelin (0.5, 1, 5, 10 and 40 microg) was given to 13 male Thoroughbred yearlings ( n=3-8 colts per dose). Jugular venous blood samples were taken at -10, 0, 10, 20, 30, 40, 60, 120 and 180 min relative to buserelin administration. Increases (P < 0.05) in LH concentrations occurred in colts that received 5, 10, or 40 microg buserelin, but not in those that received 0.5 or 1 microg. Peak LH concentrations and mean area under the curve were higher (P < 0.05) in colts receiving 40 microg busereli...
Hess EK, Reinhart JM, Anderson MJ, Jannasch AS, Taylor SD.Thiamine is a vital co-factor for several anti-inflammatory and antioxidant processes that are critical for mitigation of sepsis-associated inflammation, but pharmacokinetic (PK) analysis has not been reported in horses. We hypothesized that IV thiamine hydrochloride (TH) at increasing dosages would result in corresponding increases in plasma thiamine concentrations without causing adverse effects. A randomized cross-over study was performed in 9 healthy horses that each received TH at 5, 10, and 20 mg/kg IV. Blood was collected immediately prior to drug administration and at several time poi...
Polikepahad S, Haque M, Francis J, Moore RM, Venugopal CS.The purpose of the study was to determine and compare the expression of endothelin (ET) receptors in the peripheral lungs of healthy horses and those affected with recurrent airway obstruction (RAO) using reverse transcriptase polymerase chain reaction (RT-PCR), real-time PCR, Western blot analysis, and immunohistochemical techniques. Two groups of horses (7 healthy and 7 RAO-affected) were selected from a pool of horses destined for euthanasia. The grouping of horses was based on the history, clinical scoring, and pulmonary function testing. After euthanasia, gross postmortem evaluation of th...
Otani S, Arimitsu Y, Akama K.Antileptospiral sera from hyperimmunized horses were fractionated by gel filtration on Sephadex G-200 or by starch block electrophoresis. The fractions were examined quantitatively for leptospiricidal, agglutinating and complement fixing activities. The leptospiricidal activity was higher in the 78 globulin fraction than in the 19S globulin fraction, while the agglutinating activity was shared by both the fractions being higher in the 19S fraction. Complement fixing activity was found evenly in both the fractions. Leptospiricidal and complement fixing activities were higher in gamma-globulin t...
Wullschleger L, Weisse B, Blaser D, Fürst AE.Four radii of different horses were tested in three-point bending and in pure torsion. Detailed finite element (FE) models of these long bones were established by means of computed-tomography (CT) images and tests simulated for both load cases. For the allocation of the local isotropic material stiffness, individual exponential functions were applied whose factor and exponent were determined solely by fitting them to the measured torsional stiffness and bending stiffness of the entire bones. These stiffness functions referring directly to the CT number and having exponents between 1.5 and 2 we...
Milne EM, Pogson DM, Else RW, Rowland AC.One case of caecocaecal intussusception (case 1) and one case of caecocolic intussusception (case 2) in ponies are described. Case 1 showed mild abdominal discomfort for seven days followed by sudden death whereas case 2 showed continuous moderate pain for three weeks. At post mortem examination, case 1 showed intussusception of the base of the caecum into the body whereas in case 2, the entire caecum had invaginated into the right ventral colon. Histopathological examination showed that the lesions in both animals had been present for a long time.
Hunt JP, Haywood PE, Moss MS.A gas chromatographic screening procedure for the non-steroidal anti-inflammatory group of drugs is described. The method invovles on-column methylation of the carboxylic acid group using trimethylanilinium hydroxide as the methylating reagent. Fifteen such drugs were studied. Eight of these were detected in urine collected from horses that had received these compounds orally and for these drugs, rates of urinary excretion are recorded. Seven other members of this group of drugs were shown to be detectable by this procedure but in these cases the drug was added to urine and not administered to...
Singh AK, Mishra U, Ashraf M, Abdennebi EH, Granley K, Dombrovskis D, Hewetson D, Stowe CM.Chemical ionization- and electron impact ionization-selective ion monitoring provided a simple and sensitive method for measuring detomidine (Domosedan), a potent sedative-analgesic drug for horses and cattle. Chemical ionization was at least 10 times more sensitive than electron impact ionization. By using propranolol as an internal standard, we found that the recovery of detomidine from the extraction procedure used in this study was greater than 75% for plasma, whole blood, or urine samples. Approximately 68% of detomidine was bound to plasma protein and 53% was bound to red blood cells.
Al-Dissi A.A wide variety of toxins cause diseases in the horse and are investigated routinely by veterinarians and veterinary pathologists to identify the cause of illness and death. A complete investigation involves performing a thorough necropsy and requires macroscopic and microscopic examination of lesions and a variety of laboratory testing to obtain an accurate diagnosis. The identification of gross lesions by equine practitioners is often the first step in formulating a diagnostic plan. This article provides a description of selected common toxins producing detectable gross lesions in horses in N...
Stiglhuber A, Breit S, König HE.The equine fetlock joint cavity shows ten pouches. The dorsal recess, which is oriented to the proximal side, is separated from those three pouches, which show to the distal direction, by several capsular folds. These folds are documented by means of sagittal sections through the fetlock joint. A medial/lateral recess is covered by the deep part of the collateral ligament of the fetlock joint. The collateral ligaments as well as the sesamoidean collateral ligaments are closely connected with the joint capsule, from which two capsular folds are separated. Between the part of the sesamoidean col...
Lehner AF, Almeida P, Jacobs J, Harkins JD, Karpiesiuk W, Woods WE, Dirikolu L, Bosken JM, Carter WG, Boyles J, Holtz C, Heller T, Nattrass C....Remifentanil (4-methoxycarbonyl-4-[(1-oxopropyl)phenylamino]-1-piperidinepropionic acid methyl ester) is a mu-opioid receptor agonist with considerable abuse potential in racing horses. The identification of its major equine urinary metabolite, 4-methoxycarbonyl-4-[(1-oxopropyl)phenylamino]-1-piperidinepropionic+ ++ acid, an ester hydrolysis product of remifentanil is reported. Administration of remifentanil HCl (5 mg, intravenous) produced clear-cut locomotor responses, establishing the clinical efficacy of this dose. ELISA analysis of postadministration urine samples readily detected fentany...
Page AE, Stills HF, Horohov DW.In the horse, Lawsonia intracellularis infection results in equine proliferative enteropathy (EPE). While upwards of 100% of weanlings on an endemic farm may seroconvert, only a small percentage (approximately 5%) will develop clinical disease. Cell-mediated immune mechanisms likely play a role in resistance to L. intracellularis and the absence of a L. intracellularis-specific IFN-γ response has been associated with the development of EPE. The goal of this study was to determine whether protection from clinical EPE is associated with the induction of a systemic IgG sub-isotypic response cons...
Apprich V, Spergser J, Rosengarten R, Stanek C.The effects of two dermatophytes (Microsporum gypseum and Trichophyton mentagrophytes) and four moulds (Scopulariopsis brevicaulis, Alternaria alternata, Geotrichum candidum and Penicillium spp.) on living keratinocyte cultures were examined in vitro using primary human keratinocytes. Rates of apoptosis of infected cells were determined using a colorimetric TUNEL system which detects the characteristic nuclear DNA fragmentation of apoptotic cells. The cytotoxicity of the individual fungi was tested by quantitatively measuring cytosolic enzyme lactate dehydrogenase, released upon cell lysis, in...
Sim RR, Padilla LR, Joyner PH, Anikis P, Aitken-Palmer C.Anaplasma phagocytophilum (formerly Ehrlichia equi ) is a tickborne pathogen of domestic horses and the causative agent of equine granulocytic anaplasmosis. After the occurrence of clinical anaplasmosis in a Przewalski's horse ( Equus ferus przewalskii) housed at the Smithsonian Conservation Biology Institute in 2008, opportunistic serosurveillance of the herd was initiated. From 2008 to 2014, 57 serum samples were collected from 27 individuals (10 males; 17 females). Using indirect immunofluorescent antibody assays for anti- Anaplasma phagocytophilum antibodies, it was determined that prevale...
Timoney JF.An R antigen of the group C streptococcus S. equi that cross reacts with a similar antigen of S. zooepidemicus has been identified and characterized. It is acid, heat and trypsin resistant, but pepsin sensitive and has an isoelectric point of 4.8. The amino acids in highest concentration are glutamic, aspartic, alanine, leucine, and valine. Bacterial components released in a French Press contain large amounts of R antigen, which is present also in culture supernatants and acid extracts. It has a molecular weight of about 82,000. Trypsin extraction of cells yields molecules of predominantly 56,...
Miller PJ, Holmes JR.Systolic time intervals (STIs), isovolumic contraction time (ICT) and left ventricular ejection time (LVET) were recorded from seven horses with supraventricular arrhythmia. The STIs were measured over a number of beats (33 to 100) directly from the left ventricular (LV) and aortic (Ao) pressure contours which were recorded simultaneously using two catheter-mounted transducers. ICT was significantly (P less than 0.01) and directly related to beat-by-beat heart rate (HR = 60/pulse interval) and LVET was significantly (P less than 0.01) and inversely related to heart rate in each of five horses....
Al-Wabel NA.Semicarbazide-sensitive amine oxidase (SSAO) activity was measured spectrophotometrically using benzylamine as a substrate, in the serum of healthy males and females of horses, camels, cattle, sheep and goats. The animals were born and raised in the same area, and the blood collection was made on the same day to avoid variations. Also the concentrations of protein and copper were measured in the same samples. There were no significant gender-related differences in SSAO activity between the tested animals regardless of species. Activities of SSAO in either male or female of horse were significa...
Kuroda T, Minamijima Y, Niwa H, Mita H, Tamura N, Fukuda K, Kuwano A, Sato F.Cephalothin (CET) concentrations in body fluids (plasma, synovial fluid, pleural fluid, peritoneal fluid, and aqueous humor) and tissue samples (bone, lung, jejunum, hoof, and subcutaneous tissue) were investigated to consider the treatment of infectious diseases in horses. CET 22 mg/kg body weight was intravenously administered to 12 horses. Samples were collected from four different horses at 1, 3, and 5 hr after administration. The CET concentration in body fluids other than aqueous humor was maintained above the MIC90 values of Streptococcus zooepidemicus and Staphylococcus aureus until 5 ...
Le Goff D, Pastier D, Hannan Y, Petit E, Ayrault-Jarrier M, Nouvelot A.1. Equine lipoproteins were isolated from plasma by density gradient ultracentrifugation and apolipoprotein composition determined by SDS-polyacrylamide gel electrophoresis. 2. VLDL and IDL were present at low concentration (0.2 mg/ml). Two apoB components of Mr corresponding to human apoB-100 and one apoB-48-like component were represented in VLDL fraction. 3. LDL-1 and LDL-2 subfractions have displayed an almost equal concentration (0.4 mg/ml). Two apoB-100-like components were the major apolipoproteins in each fraction. Small amounts of apoB-48-like component were detectable in LDL-1 and LD...
Gareau L.Over the past decade, the cattle industry has experienced practically a full circle. With the promising beef prices in the early 1970s, with the glut of grain and a generous assist from government incentive programs, the forage acreage and cattle population have increased at a record rate. By 1974, the tide began to turn - grain prices went up sharply and beef prices became sluggish - and by 1976 a major crisis faced the producers. The cattle industry which had been developing on a cheap grain economy was now obliged to rely more on forage for its survival. Unfortunately, the forage was not ex...
Hinrichs K, Betschart RW, McCue PM, Squires EL.Mares with preovulatory follicles >33 mm in diameter were administered hCG and were randomly assigned for aspiration of the dominant follicle at 24 h or 35 h after hCG administration. Oocytes recovered at 24 h were cultured for 12 h before transfer and oocytes recovered at 35 h were cultured for 1 h. Oocytes were transferred by flank laparotomy to the oviduct of the same mare, or to the oviduct of another oocyte donor. Recipient mares were inseminated before and after transfer. The oocyte recovery rates at 24 h and 35 h after hCG administration were not significantly different (10/15 (66%) and...
Blikslager AT, Bristol DG, Bowman KF, Engelbert TA.To determine the feasibility of performing a single-incision loop colostomy for treatment of grade-3 rectal tears in horses. Methods: Retrospective case series. Methods: Seven adult horses with grade-3 rectal tears. Methods: A single-incision loop colostomy was performed with horses under general anesthesia (n = 6) or while restrained in standing stocks (n = 1). The rectal tear was lavaged via an endoscope. The colostomy was resected after the rectal tear healed. Results: Rectal tears ranged from 4 to 10 cm in diameter and were > 25 cm proximal to the anus. All horses survived colostomy surger...
Milne EM, Pemberton AD, McGorum BC, Dixon PM, Miller HR.The equine alpha-1 proteinase inhibitor (alpha 1PI) system differs from that of man in that the equine system consists of four closely-linked genes (Spi1-Spi4) whereas in man, a single gene encodes for alpha 1PI. We have previously found differences in the proportion of the Spi proteins in equine serum and bronchoalveolar lavage fluid (BALF). We therefore wished to determine whether, as reported in man, there was any molecular weight difference between the Spi proteins in serum and BALF. alpha 1PI and albumin from equine BALF migrated further towards the anode compared with serum alpha 1PI on ...
Thompson MA, McCann BE, Simmons RB, Rhen T.Contraceptive vaccines are used to reduce birth rates in wild and feral animal populations. While the immunocontraceptive GonaCon-Equine has proven effective in reducing fertility among female feral horses, there is individual variation in the duration of infertility following treatment. To identify genetic factors influencing the effectiveness of GonaCon-Equine, we conducted a genome-wide association study of 88 mares from a feral population genotyped using the Illumina GGP Equine 70k SNP array. Contraceptive treatment schedules and long-term foaling rates have been recorded for each individu...
