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.
Sadet-Bourgeteau S, Philippeau C, Dequiedt S, Julliand V.The horse's hindgut bacterial ecosystem has often been studied using faecal samples. However few studies compared both bacterial ecosystems and the validity of using faecal samples may be questionable. Hence, the present study aimed to compare the structure of the equine bacterial community in the hindgut (caecum, right ventral colon) and faeces using a fingerprint technique known as Automated Ribosomal Intergenic Spacer Analysis (ARISA). Two DNA extraction methods were also assessed. Intestinal contents and faeces were sampled 3 h after the morning meal on four adult fistulated horses fed mea...
Peffers MJ, Thorpe CT, Collins JA, Eong R, Wei TK, Screen HR, Clegg PD.Energy storing tendons, such as the human Achilles and equine superficial digital flexor tendon (SDFT), are highly prone to injury, the incidence of which increases with aging. The cellular and molecular mechanisms that result in increased injury in aged tendons are not well established but are thought to result in altered matrix turnover. However, little attempt has been made to fully characterize the tendon proteome nor determine how the abundance of specific tendon proteins changes with aging and/or injury. The aim of this study was, therefore, to assess the protein profile of normal SDFTs ...
Posta J, Rudiné Mezei A, Mihók S, Mészáros G.The aim of this study was to analyse the duration of the competitive life of jumping horses in Hungary to assess the potential for genetic evaluation and to get information about the risk factors affecting jumping performance of sport horses. The data set included lifetime performance in jumping competitions for 8475 horses born from 1992 onwards with records between 1996 and 2011 (32.7% were right-censored). Longevity was measured as the number of years spent in the competition. Discrete time survival model included fixed effects of gender, age at first competition, and the time-dependent eff...
Kelmer G, Tatz AJ, Famini S, Bdolah-Abram T, Soback S, Britzi M.Regional limb perfusion (RLP) significantly decreases morbidity and mortality associated with distal limb injuries in horses. There is an urgent need for finding additional effective antimicrobial drugs for use in RLP. In this study, we tested the pharmacokinetics (PK) of chloramphenicol in RLP. Eight horses participated in the study, which was approved by the University Animal Care and Use Committee. The cephalic and the saphenous veins were used to perfuse the limbs. Synovial samples were collected from the metacarpo/metatarsophalangeal (MCP/MTP) joint. The Friedman Test was applied for asse...
Grimsrud KN, Ait-Oudhia S, Durbin-Johnson BP, Rocke DM, Mama KR, Rezende ML, Stanley SD, Jusko WJ.The present study characterizes the pharmacokinetic (PK) and pharmacodynamic (PD) relationships of the α2-adrenergic receptor agonists detomidine (DET), medetomidine (MED) and dexmedetomidine (DEX) in parallel groups of horses from in vivo data after single bolus doses. Head height (HH), heart rate (HR), and blood glucose concentrations were measured over 6 h. Compartmental PK and minimal physiologically based PK (mPBPK) models were applied and incorporated into basic and extended indirect response models (IRM). Population PK/PD analysis was conducted using the Monolix software implementing t...
Wooldridge AA, Waguespack RW, Schwartz DD, Venugopal CS, Eades SC, Beadle RE.Hyperinsulinemia causes laminitis experimentally and is a risk factor for naturally occurring laminitis. The aim of this study was to investigate the effects of insulin on laminar vascular relaxation and to induce insulin-associated vascular dysfunction in vitro. Relaxation responses of isolated laminar arterial and venous rings to acetylcholine and insulin were evaluated. To alter vascular function in response to insulin, all vessel rings were incubated with insulin or vehicle, submaximally contracted, administered insulin again and relaxation responses recorded. Laminar arteries were also in...
Lechartier A, Rossignol F, Brandenberger O, Vitte A, Mespoulhès-Rivière C, Rossignol A, Boening KJ.To compare mechanical properties of 2 techniques with a conventional technique for anchoring the muscular process in a laryngoplasty procedure. Methods: Experimental ex vivo study. Methods: Equine larynges (n = 60). Methods: A single loop (SL), a screw (SC), and a double loop technique (DL) were compared. Constructs were subjected to cyclic loading, oscillating from 5 to 50 N for 3000 cycles, followed by a single cycle to failure test. Mean distraction, load at failure, stiffness, and failure mode were compared between groups. Results: Mean ± SD distraction in cyclic loading was greater for D...
Braga PC, Dal Sasso M, Lattuada N, Greco V, Sibilia V, Zucca E, Stucchi L, Ferro E, Ferrucci F.Activated neutrophils (PMNs), the ROS/RNS released by PMNs and the derived inflammatory processes are involved in the pathogenesis and progression of human inflammatory airway diseases. Similar diseases are also present in horses which suffer from recurrent airway obstruction (RAO), exercise-induced pulmonary haemorrhage (EIPH) and inflammatory airway diseases (IAD). Hyaluronic acid (HA) plays numerous roles in modulating inflammatory processes. The aim of this study was to examine whether a preparation of HA (MW 900 000 Da) interferes with ROS/RNS during the course of equine PMN respiratory b...
Ben Hassine T, De Massis F, Calistri P, Savini G, BelHaj Mohamed B, Ranen A, Di Gennaro A, Sghaier S, Hammami S.In the last fifteen years, West Nile Virus (WNV) has dramatically expanded its geographic range and is now considered the most widespread arbovirus in the world. In Tunisia, West Nile Fever (WNF) outbreaks were reported in humans in 1997, 2003 and 2012. Usutu Virus (USUV), which is a 'new' emerging Flavivirus antigenically close to WNV, has never been reported in Tunisia. A serological investigation in 284 equids was conducted in 2012 in the southern west region of the country to assess the presence and prevalence of the WNV and USUV infection. Of the 284 samples tested by competitive enzyme-l...
Rezende ML, Grimsrud KN, Stanley SD, Steffey EP, Mama KR.The aim of the study was to describe the pharmacokinetics and selected pharmacodynamics of intravenous dexmedetomidine in horses. Eight adult horses received 5 μg/kg dexmedetomidine IV. Blood samples were collected before and for 10 h after drug administration to determine dexmedetomidine plasma concentrations. Pharmacokinetic parameters were calculated using noncompartmental analysis. Data from one outlier were excluded from the statistical summary. Behavioral and physiological responses were recorded before and for 6 h after dexmedetomidine administration. Dexmedetomidine concentrations dec...
Bingham AM, Burkett-Cadena ND, Hassan HK, McClure CJ, Unnasch TR.Studies investigating winter transmission of Eastern equine encephalitis virus (EEEV) were conducted in Hillsborough County, Florida. The virus was detected in Culiseta melanura and Anopheles quadrimaculatus in February 2012 and 2013, respectively. During the winter months, herons were the most important avian hosts for all mosquito species encountered. In collections carried out in the summer of 2011, blood meals taken from herons were still common, but less frequently encountered than in winter, with an increased frequency of mammalian- and reptile-derived meals observed in the summer. Four ...
Pedersen PJ, Moeller SB, Flethøj M, Kanters JK, Buhl R, Klaerke DA.Irregularities in cardiac repolarization are known to predispose for arrhythmias and sudden cardiac death in humans. The QT interval is a quantitative measurement of repolarization, and clinically, the QTc (QT interval corrected for heart rate) and Tpeak to Tend intervals (TpTe) are used as repolarization markers. To support the use of these markers in horses, we sought to describe the possible influence of the environment, time of day, day-to-day effects, T wave conformation, age, body weight (BW), and horse-to-horse variation on repolarization measurements. Methods: 12 Warmblood geldings, ag...
Ons E, Van Brussel L, Lane S, King V, Cullinane A, Kenna R, Lyons P, Hammond TA, Salt J, Raue R.The efficacy of Zylexis®, an immunomodulator in horses based on inactivated Parapoxvirus ovis (iPPVO), was assessed using an equine herpesvirus type 1 (EHV-1) challenge model in the presence of a natural infection with Streptococcus equi equi (S. equi). Eleven horses were treated with iPPVO and twelve were kept as controls. Six horses were challenged with EHV-1 and commingled with the horses on study. Animals were dosed on Days -2, 0 (just before commingling) and Day 7. On Day 11 significantly less nasal discharge, enlarged lymph nodes, EHV-1 shedding and lower rectal temperatures were observ...
Santonastaso A, Hardy J, Cohen N, Fajt V.In certain situations, an alternate route for parenteral drug administration in horses may be useful. The intra-osseous (IO) route may provide a safe alternative to the intravenous (i.v.) route for administration of sedatives to horses when the i.v. route is inaccessible or undesirable. Six adult horses were administered xylazine i.v. or IO in a block-randomized crossover design. For the i.v. trial, both jugular veins were catheterized, and one was used for xylazine administration, while the other was used for blood collection. For the IO trial, one jugular vein was catheterized for blood coll...
Dymock DC, Brown MP, Merritt KA, Trumble TN.To determine whether stromal cell-derived factor-1 (SDF-1) concentrations in serum, plasma, and synovial fluid differed among untrained, race-trained, and osteochondral-injured Thoroughbred racehorses. Methods: 22 racehorses without osteochondral injury and 37 racehorses with osteochondral injury. Methods: Horses without osteochondral injury were examined before and after 5 to 6 months of race training. Horses with osteochondral injury were undergoing arthroscopic surgery for removal of osteochondral fragments from carpal or metacarpophalangeal or metatarsophalangeal joints (fetlock joints). S...
Graham S, Solano M, Sutherland-Smith J, Sato AF, Maranda L.Disorders of the stifle are a common cause of lameness in horses yet the accuracy of scintigraphy for diagnosis of stifle conditions is controversial. The aim of retrospective cross-sectional study was to determine the diagnostic sensitivity (Se) of bone scintigraphy in detecting stifle disease and to determine if two orthogonal scintigraphic images improve diagnostic Se. Horses that underwent scintigraphic examination during a two-year period were included. Horses were divided into two groups: group 1 (N = 23) had lameness that was localized to the stifle by intra-articular analgesia and grou...
Watts AE, Ness SL, Divers TJ, Fubini SL, Frye AH, Stokol T, Cummings KJ, Brooks MB.To evaluate the effects of clopidogrel on clinical and clinicopathologic variables in healthy horses with experimentally induced endotoxemia. Methods: 12 adult mares. Procedures-Horses were assigned with a randomization procedure to receive clopidogrel (4 mg/kg, once, then 2 mg/kg, q 24 h; n = 6) or a placebo (6) through a nasogastric tube. After 72 hours of treatment, horses received lipopolysaccharide (LPS; 30 ng/kg, IV). Heart rate, respiratory rate, rectal temperature, CBC variables, plasma fibrinogen concentration, serum tumor necrosis factor-α concentration, plasma von Willebrand factor...
Vincze S, Brandenburg AG, Espelage W, Stamm I, Wieler LH, Kopp PA, Lübke-Becker A, Walther B.Increasing numbers of companion animals suffering from infections with methicillin-resistant Staphylococcus aureus (MRSA) have been reported in the recent past. These infections are of particular concern because of the limited treatment options for MRSA and their transferability to humans. Since MRSA lineages isolated from infected companion animals often mirror typical human epidemic strains circulating in the same region, successful strategies to combat MRSA need strong and coordinated efforts from both, the human and the veterinary field according to the "One Health" concept. Hence, to iden...
Sheta E, Ragab S, Farghali H, El-Sherif A.Electroacupuncture analgesia was used for surgery in horses and donkeys. A KWD-808 electrical stimulator was used to incrementally induce a dense, dispersed wave output at frequencies from 20 to 55 Hz, which was maintained at a frequency of 55 Hz, and to change the amplitude of the wave to the best grading number for the suggested operation in each animal. Induction of analgesia lasted for 20-30 minutes, and the effect of analgesia was maintained for 20-45 minutes depending on the type of surgery performed. The exhibited clinical signs, physical examination data, and the responses of all ani...
Campos JR, Breheny P, Araujo RR, Troedsson MH, Squires EL, Timoney PJ, Balasuriya UB.Equine arteritis virus (EAV) is the causal agent of equine viral arteritis (EVA), a respiratory and reproductive disease of equids. Some strains of EAV can cause fever, leukopenia, and dependent edema of the limbs, scrotum, and preputium in the acutely infected stallion. We hypothesized that fever and scrotal edema observed during the acute phase of the infection, but not the presence of EAV, have an adverse effect on semen quality. A group of seven stallions were intranasally inoculated with the Kentucky 84 (KY84) strain of EAV. Stallions were monitored for clinical signs of EVA until 42 days...
Ergunay K, Gunay F, Erisoz Kasap O, Oter K, Gargari S, Karaoglu T, Tezcan S, Cabalar M, Yildirim Y, Emekdas G, Alten B, Ozkul A.West Nile virus (WNV), a mosquito-borne flavivirus with significant impact on human and animal health, has recently demonstrated an expanded zone of activity globally. The aim of this study is to investigate the frequency and distribution of WNV infections in potential vectors and several mammal and avian species in Turkey, where previous data indicate viral circulation. The study was conducted in 15 provinces across Turkey during 2011-2013. In addition, the entomological study was extended to 4 districts of the Turkish Republic of Northern Cyprus. WNV exposure was determined in humans, horses...
Manuja BK, Manuja A, Dahiya R, Singh S, Sharma RC, Gahlot SK.Equine influenza (EI) is primarily an infection of the upper respiratory tract and is one of the major infectious respiratory diseases of economic importance in equines. Re-emergence of the disease, species jumping by H3N8 virus in canines and possible threat of human pandemic due to the unpredictable nature of the virus have necessitated research on devising strategies for preventing the disease. The myxovirus resistance protein (Mx) has been reported to confer resistance to Orthomyxo virus infection by modifying cellular functions needed along the viral replication pathway. Polymorphisms and...
Manuja A, Kumar P, Kumar R, Kumar B, Singha H, Sharma RK, Yadav SC.Trypanosoma evansi is the causative agent of surra, which is the most common and widespread trypansomal disease. The infection is mainly restricted to animals, but it has also been documented in human. Trypanosomes possess the thick immunogenic surface coat known as variant surface glycoprotein (VSG). The parasite modifies the VSG constantly resulting in continuous antigenic variations and thus evades the host immune response. Due to antigenic variations, vaccination against trypanosomosis is not useful. Therefore, alternate strategies to augment the immune response are required. CpG-ODN class...
Tünsmeyer J, Hopster K, Feige K, Kästner SB.To determine the agreement of high definition oscillometry (HDO) with direct arterial blood pressure measurements in normotensive, hypotensive and hypertensive horses during general anaesthesia. Methods: Experimental study. Methods: Seven healthy warmblood horses, aged 3-11 years, weighing 470-565 kg. Methods: Measurements from a HDO device with the cuff placed around the base of the tail were compared with pressures measured invasively from the facial artery. High blood pressures were induced by intravenous (IV) administration of dobutamine (5 μg kg(-1) minute(-1)) over ten minutes followed ...
Hooijberg EH, van den Hoven R, Tichy A, Schwendenwein I.A wide spectrum of laboratory tests is available to aid diagnosis and classification of equine inflammatory disease. Objective: To compare diagnostic efficacy and combined predictive capability of the myeloperoxidase index (MPXI), and plasma fibrinogen, iron and serum amyloid A (SAA) concentrations for the diagnosis of inflammation. Methods: Twenty-six hospitalized horses with systemic inflammation (SI), 114 with local inflammation (LI) and 61 healthy horses or those with noninflammatory disease (NI) were included. Methods: A retrospective study was performed; clinicopathologic data from horse...
Song KD, Cho HW, Lee HK, Cho BW.The objective of this study was to determine the molecular characteristics of the horse vascular endothelial growth factor alpha gene (VEGFα) by constructing a phylogenetic tree, and to investigate gene expression profiles in tissues and blood leukocytes after exercise for development of suitable biomarkers. Using published amino acid sequences of other vertebrate species (human, chimpanzee, mouse, rat, cow, pig, chicken and dog), we constructed a phylogenetic tree which showed that equine VEGFα belonged to the same clade of the pig VEGFα. Analysis for synonymous (Ks) and non-synonymous sub...
Khrustaleva TA, Khrustalev VV, Barkovsky EV, Kolodkina VL, Astapov AA.The SF23 peptide corresponding to the receptor binding fragment of diphtheria toxin (residues 508-530) has been synthesized. This fragment forming a protruding beta hairpin has been chosen because it is the less mutable B-cell epitope. Affine chromatography and ELISA show that antibodies from the sera of persons infected by toxigenic Corynebacterium diphtheriae and those immunized by diphtheria toxoid are able to bind the synthetic SF23 peptide. There are antibodies recognizing the SF23 peptide in the serum of horses hyperimmunized with diphtheria toxoid. Analysis of circular dichroism spectra...
Carmalt JL, Borg H, Näslund H, Waldner C.The aim of this study was to determine whether horses with a proximal palmar/plantar first phalangeal osteochondral fragment (POF) had comparable racing careers (prior to and following surgery) to horses without this fracture. A retrospective cohort study included 174 Swedish Standardbred trotters with osteochondral fragmentation in the palmar/plantar fetlock joint and 613 radiographically negative control horses presented for prepurchase examinations. Medical records and radiographs were examined for each horse. Racing data were retrieved from online Swedish Standardbred harness racing record...
Clark RK, Galantino-Homer HL.Equine laminitis is a common, painful, debilitating condition of the hoof that is a leading cause of disability in horses, often necessitating euthanasia. The equine hoof represents an extreme evolutionary adaptation of an epidermal structure homologous to the human or murine nail units. Immunohistochemistry is frequently utilized in the study of the pathophysiology of laminitis. The complex, multilayered, extensively interdigitated epidermal-dermal lamellar interface renders precise interpretation of immunofluorescence localization difficult, especially when effective technique and reagents r...
Beccati F, Gialletti R, Passamonti F, Nannarone S, Di Meo A, Pepe M.Septic arthritis/tenosynovitis in the horse can have life-threatening consequences. The purpose of this cross-sectional retrospective study was to describe ultrasound characteristics of septic arthritis/tenosynovitis in a group of horses. Diagnosis of septic arthritis/tenosynovitis was based on historical and clinical findings as well as the results of the synovial fluid analysis and/or positive synovial culture. Ultrasonographic findings recorded were degree of joint/sheath effusion, degree of synovial membrane thickening, echogenicity of the synovial fluid, and presence of hyperechogenic spo...
Dart AJ, Cries L, Jeffcott LB, Hodgson DR, Rose RJ.To evaluate the effect of intramuscular administration of recombinant equine growth hormone on healing of full thickness skin wounds on equine limbs. Methods: Experimental. Methods: Nine Standardbred horses. Methods: In study 1, standardized full thickness skin wounds (2.5 x 2.5 cm) were made over the dorsomedial aspect of the mid-cannon bone of 1 forelimb and 1 hindlimb in 9 horses. Wounds were bandaged without treatment (control subjects) and videorecorded twice weekly until healed. Then, in study 2, similar wounds were created on the opposite limbs; 6 horses were administered intramuscular ...
Aviles G, Bianchi TI, Daffner JF, Sabattini MS.It is shown here the WEE virus activity in ARgentina in 1983-1986 post-epizootic period. A surveillance system was established by the equine case notification and the sentinel animal method. Among the thirteen equine focus notified between September 1983-September 1985 in Córdoba and Santa Fe Provinces, 5 presumptive cases out of 16 sick horses were confirmed by the hemagglutination inhibition test for WEE epizootic virus. Twenty eight notified human cases were studied with negative results. The neutralizing antibody (Ac NT) prevalence among sentinel horses in Córdoba Province (4%) was lower...
Lyons ET, Tolliver SC, Collins SS.Population B, drug-resistant small strongyles have been studied in naturally infected horses in Kentucky for more than 40 years. These parasites first were found to be resistant to phenothiazine (PTZ) and thiabendazole (TBZ), later to other parasiticides. Studies have been on evaluation of antiparasitic efficacy of several compounds, especially the benzimidazoles, against Population B small strongyles in clinical (field) tests (1959-1983) on the commercial farm of origin and in clinical and critical tests (1966-2001) at the University of Kentucky (UK) research farm. Research on these nematodes...
Loftus JP, Belknap JK, Stankiewicz KM, Black SJ.REASONS FOR STUDY: Xanthine oxidase (XO)-dependent production of superoxide anion and hydrogen peroxide, a characteristic of ischaemia-reperfusion injury, may contribute to the development of equine laminitis. Objective: To determine the levels of XO and antioxidant enzymes (catalase, superoxide dismutase [SOD]) in the digital laminae of normal horses (CON) and horses in the developmental stage of laminitis using the black walnut extract (BWE) model. Methods: Healthy horses (n = 12) were administered BWE (BWE group, n = 6), or water (CON group, n = 6) through a nasogastric tube. At the onset o...
Zink MC, Johnson JA.Bronchoalveolar lavage was performed 5 times, sequentially, on 3 healthy foals when each was between 2 and 63 days of age. Total and differential counts were performed on recovered cells. The lungs of foals less than 19 days of age contained few alveolar macrophages recoverable by bronchoalveolar lavage. This number increased sharply during the first 2 to 3 weeks of life, but remained relatively constant subsequently. Approximately 86% of the alveolar cells in the lungs of foals up to 3 weeks of age were alveolar macrophages. During the first 2 months of life, this number decreased to approxim...
James KE, Smith WA, Conrad PA, Packham AE, Guerrero L, Ng M, Pusterla N.OBJECTIVE To describe the general seroprevalence of anti-Sarcocystis neurona and anti-Neospora hughesi antibodies among healthy equids by use of indirect fluorescent antibody tests and determine potential risk factors for seropositivity. DESIGN Cross-sectional study. SAMPLE Whole blood samples collected from 5,250 equids (1 sample/animal) across 18 states in the United States during October 2013. PROCEDURES Information regarding potential risk factors (geographic region, breed, primary use, sex, and age) was collected along with the blood samples. For each equid, an indirect fluorescent antibo...
Collins N, Milne E, Hahn C, Dixon P.The establishment of a single validated endoscopic laryngeal grading system for assessing recurrent laryngeal neuropathy (RLN) is desirable to facilitate direct comparisons between the findings of different clinical and research groups worldwide. The objective of this study was to assess the relationship between the Havemeyer endoscopic laryngeal grading system and histopathological changes consistent with RLN in the left cricoarytenoideus dorsalis (CAD) muscle of horses of different breeds with a full range of clinical severities of RLN, i.e., from normal endoscopic laryngeal function to comp...
Tidswell HK, Innes JF, Avery NC, Clegg PD, Barr AR, Vaughan-Thomas A, Wakley G, Tarlton JF.Fatigue fracture of cuboidal bones occurs in the human foot as well as the equine carpus. The racehorse provides a naturally-occurring model to study the effects of high-intensity exercise on the morphology and metabolism of cuboidal bones. We studied both the mineral and the collagenous matrix of the third (C(3)) and radial (C(r)) carpal bones of raced and non-raced Thoroughbred (TB) horses. We hypothesised that racehorses would show increases in the mineral component of these bones and post-translational modifications of the collagenous matrix alongside changes in markers of collagen remodel...
Page PC, Labuschagne K, Venter GJ, Schoeman JP, Guthrie AJ.The efficacy of alphacypermethrin-treated high density polyethylene (HDPE) mesh applied to jet stalls against Culicoides biting midges (Diptera: Ceratopogonidae) was determined by mechanical aspiration of midges from horses and using Onderstepoort 220 V downdraught black light traps in four blocks of a 3 × 2 randomised design under South African field conditions. The alphacypermethrin-treated HDPE mesh applied to the stall significantly (P = 0.008) reduced the number of Culicoides midges, predominantly Culicoides (Avaritia) imicola Kieffer, mechanically aspirated from horses housed in the sta...
Zhou W, Cook RF, Cook SJ, Hammond SA, Rushlow K, Ghabrial NN, Berger SL, Montelaro RC, Issel CJ.The env gene is an excellent candidate for inclusion in any DNA-based vaccine approach against equine infectious anemia virus (EIAV). Unfortunately, this gene is subjected to mutational pressure in E. coli resulting in the introduction of stop codons at the 5' terminus unless it is molecularly cloned using very-low-copy-number plasmid vectors. To overcome this problem, a mammalian expression vector was constructed based on the low-copy-number pLG338-30 plasmid. This permitted the production of full-length EIAV env gene clones (plcnCMVenv) from which low-level expression of the viral surface un...
Chateau H, Degueurce C, Denoix JM.Sharp turns are suspected to increase expression of several distal forelimb lamenesses even at the walk but the biomechanical consequences of such a movement remain unknown. Objective: To quantify the effects of a sharp turn at the walk on the 3-dimensional movements of the distal segments of the forelimb. Methods: Kinematics of the distal segments were measured in 4 healthy horses invasively with an ultrasonic system. Three-dimensional rotations of the digital joints were calculated by use of a joint coordinate system. Data obtained for a turn at the walk were compared to those obtained in a ...
Eyre P, Elmes PJ, Strickland S.Spirally cut digital arteries and veins were mounted isotonically in organ baths containing oxygenated Krebs' Q-Henseleit solution. Twelve arterial and 12 venous preparations all contracted dose dependently when epinephrine, norepinephrine, serotonin, or histamine were added to the bathing fluid. Addition of hydrocortisone or betamethasone alone did not cause contractions in any of the tissues tested. However, when hydrocortisone or betamethasone was added to vessel strips that were partially contracted (40% to 60% maximal) by epinephrine, norepinephrine, or serotonin, each vessel strip invari...
Castro ER, Arbiza J.Infection with equid alphaherpesvirus 1 (EHV-1) causes respiratory disease, abortion and neurological disorders in horses. Molecular epidemiology studies have demonstrated that a single nucleotide polymorphism (A2254/G2254) in the genome region of open reading frame 30 which results in an amino acid variation (N752/D752) of the EHV-1 DNA polymerase, is significantly associated with the neuropathogenic potential of naturally occurring strains. In recent years, an increase in the number of cases of equine neurological disease caused by neuropathogenic variants of EHV-1 has been observed in numer...
Jindra C, Hainisch EK, Brandt S.Horses and other equid species are frequently affected by bovine papillomavirus type 1 and/or 2 (BPV1, BPV2)-induced skin tumors termed sarcoids. Although sarcoids do not metastasize, they constitute a serious health problem due to their BPV1/2-mediated resistance to treatment and propensity to recrudesce in a more severe, multiple form following accidental or iatrogenic trauma. This review provides an overview on BPV1/2 infection and associated immune escape in the equid host and presents early and recent immunotherapeutic approaches in sarcoid management.
Engen RL, Clark CL.High-performance liquid chromatography (HPLC) was used to determine the phospholipid (PL) composition of ovine, equine, bovine, porcine, and canine RBC membranes. Procedural modifications of established techniques provided for separation of 7 PL within a 15- to 20-minute sample run. Significant (P less than 0.05) differences were detected in RBC membrane PL composition among the various species. The concern for physiologic properties associated with hemolysis and/or sedimentation rate must include evaluation of differences in the PL bilayer structure.
Nagata S, Miyake YI, Nambo Y, Nagamine N, Watanabe G, Tsunoda N, Taniyama H, Hondo E, Yamada J, Taya K.To examine the physiological role of inhibin in the stallion, a heterologous radioimmunoassay (RIA) based on a bovine RIA was validated and used to measure immunoreactive (ir)-inhibin concentrations in plasma and testicular homogenates. The bioactivity of equine testicular inhibin was also examined using an assay for suppression of FSH secretion from rat anterior pituitary cells. In addition, to identify the cell responsible for secreting testicular inhibin, the localisation of inhibin in the testis was investigated by an immunohistochemical method using a polyclonal antibody against (Tyr30)-p...
Frellstedt L, McKenzie HC, Barrett JG, Furr MO.Endotoxemia is responsible for severe illness in horses. Individuals can become clinically unresponsive to the endotoxin molecule after an initial exposure; a phenomenon referred to as 'endotoxin tolerance' (ET). ET has been observed clinically in horses in vivo; however, cytokine expression associated with ET has not been investigated. The purpose of this study was to develop and validate a method for inducing ET in equine peripheral blood mononuclear cells (PBMC) in vitro, and to describe selected cytokine responses which are associated with ET. ET was induced by culturing cells with three c...
Rossdale PD, Cash RS, Leadon DP, Jeffcott LB.Total protein content and a variety of enzyme activities and electrolyte values were determined in 73 cerebrospinal fluid (CSF) samples from 66 horses and ponies. The foals (48) were divided into 3 categories-spontaneously delivered normal foals (Group A), full term induced normal foals (Group B) and premature induced non-surviving foals (Group C). CSF samples from a group of 18 normal adults (Group D) were included for comparison. Paired serum and CSF samples were collected on 32 occasions and subjected to similar analyses. CSF sodium and chloride were always higher than serum sodium and chlo...
Lentz LR, Valberg SJ, Herold LV, Onan GW, Mickelson JR, Gallant EM.To determine whether alterations in myoplasmic calcium regulation can be identified in muscle cell cultures (myotubes) and intact muscle fiber bundles derived from Thoroughbreds affected with recurrent exertional rhabdomyolysis (RER). Methods: 6 related Thoroughbreds with RER and 8 clinically normal (control) Thoroughbred or crossbred horses. Methods: Myotube cell cultures were grown from satellite cells obtained from muscle biopsy specimens of RER-affected and control horses. Fura-2 fluorescence was used to measure resting myoplasmic calcium concentration as well as caffeine- and 4-chloro-m-c...
Issouf M, Vargas A, Boivin R, Lavoie JP.Airway wall remodeling, including hyperplasia and hypertrophy of smooth muscle (ASM) cells leading to an increased smooth muscle mass, is considered central to asthma. However, molecular pathways responsible for ASM remodeling remain poorly understood. MicroRNAs (miRNAs) have emerged as key regulators of inflammatory and repair processes affecting the lungs and can downregulate protein expression by inhibiting target mRNA translation. We therefore hypothesized that miRNAs are involved in ASM remodeling in asthma by modulating ASM proliferation. We have analyzed the expression of miRNAs in bron...
Ho EN, Kwok WH, Lau MY, Wong AS, Wan TS, Lam KK, Schiff PJ, Stewart BD.A veterinary preparation known as TB-500 and containing a synthetic version of the naturally occurring peptide LKKTETQ has emerged. The peptide segment (17)LKKTETQ(23) is the active site within the protein thymosin β(4) responsible for actin binding, cell migration and wound healing. The key ingredient of TB-500 is the peptide LKKTETQ with artificial acetylation of the N-terminus. TB-500 is claimed to promote endothelial cell differentiation, angiogenesis in dermal tissues, keratinocyte migration, collagen deposition and decrease inflammation. In order to control the misuse of TB-500 in equin...
Schneider N, Lejeune JP, Deby C, Deby-Dupont GP, Serteyn D.Ischaemia and reperfusion are suspected to alter chondrocyte metabolism. Here, we studied the effects of three oxygen (O2) tensions on the viability of equine articular chondrocytes isolated from the cartilage of the distal interphalangeal joint of horses. Chondrocytes were cultured in alginate beads under 1%, 5% or 21% gas phase O2 concentration for 14 days, cellular growth kinetics were measured (n=6), and the cells were observed by light microscopy after staining for necrotic and apoptotic cell detection. For information about the metabolic status, the intracellular adenosine triphosphate (...
Teifke JP, Weiss E.Unfixed and formalin-fixed frozen sections and paraffin-sections of histopathologically confirmed sarcoids of 20 horses were studied in the PCR. The used set of primers was located in the E5 open reading frame fitting both to bovine papillomavirus 1 (BPV-1) and BPV-2. Independent of the quality of the used tissues BPV-DNA was detected in all 20 sarcoids. By cleaving with restriction endonuclease Bst XI it was shown that the DNA-sequences amplified by PCR were identical with that of BPV-1. The results support the general view that BPV play an important role in equine sarcoids.
Santschi EM, Leibsle SR, Morehead JP, Prichard MA, Clayton MK, Keuler NS.There is little information available about conformational changes in the forelimbs of growing foals. Objective: To describe the conformation of the carpus and fetlock of Thoroughbred foals from birth to yearling sale age. Methods: Subjective assessments of the fetlock and carpal conformation of 119 Thoroughbred foals were made within the first month of life and then at 30 day intervals until at least age 120 days. At least 70 subjects were examined further at 60 day intervals until September of their second year. Conformation grades are reported for 5 age groups: first 7 days and at a mean of...
Elshafie EI, Sani RA, Hassan L, Sharma R, Bashir A, Abubakar IA.Apart from occasional reports of clinical disease affecting horses, there is no information about Trypanosoma evansi in horses in Peninsula Malaysia. Thus, a cross-sectional study was conducted in eight states in Peninsula Malaysia to determine the active presence of T. evansi in horses. A total of 527 blood samples were obtained and examined by haematocrit centrifugation technique (HCT), Giemsa-stained thin blood smear (GSS), morphometric measurements, polymerase chain reaction (PCR) and cloning of PCR products. The results showed an overall parasitological prevalence of 0.57% (3/527, CI: 1.6...
Hartmann E, Christensen JW, Keeling LJ.The intensity with which a horse responds to separation from its group and subsequently to being alone is relevant for both horse and handler safety. Identification of training methods that may reduce responses to separation would be useful in practice. Objective: To investigate whether the initial presence of a familiar companion horse modifies responses to separation from the group, lowers stress levels (as measured by heart rate) and increases training efficiency. Objective: Habituation to separation proceeds more quickly if the horse is first trained with a companion, and heart rate is low...
Schwinghamer R, Massolo A, Knight C, Klein C.This study evaluated equine endometrial explants following 12, 24, and 48 hr in culture. Measurement of an indicator of cell death in explant supernatant, light microscopy, and gene expression of biomarkers of endometrial function and cellular stress were used to compare the effect of six different media on explant viability and morphology. Viability of explants was assessed indirectly through measuring LDH activity in the culture supernatant. Regardless of culture medium composition, a significant increase in LDH activity was observed within 12 hr of culture, indicating occurrence of cell dam...