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.
Tulloch JSP, Fleming KM, Pinchbeck G, Forster J, Lowe W, Westgarth C.Animal-related injuries pose a significant risk to the veterinary profession. This study aimed to describe the incidence, demographics, context and consequences of animal-related injuries at UK veterinary schools. A multicentre audit of accident records (2009-2018) across five UK veterinary schools was performed. Injury rates were stratified by school, demographics and species. The context and cause of the injury were described. Multivariable logistic models explored factors associated with medical treatment, hospital visits and time off work. An annual rate of 2.60 (95% confidence interval 2....
Hoerdemann M, Yarbrough T.To describe the technique, postoperative complications, and outcome after autologous fascia lata grafting with conjunctival flap overlay in horses with ulcerative keratitis and keratomalacia. Methods: Retrospective case series. Methods: Eleven horses with ulcerative keratitis and keratomalacia. Methods: Horses included had undergone fascia lata grafting with conjunctival flap overlay due to impending or recent corneal perforation. Preceding therapy, lesion characteristics, postoperative complications, and short- and long-term outcomes were recorded. Results: Postoperative complications include...
Leon A, Pillon C, Tebourski I, Bruyas JF, Lupo C.Abortions in horses represent an important health and economic challenge for equine industry. Primary causes of abortion are divided in non-infectious and infectious. Non-infectious causes include abnormalities of foetal appendices (umbilical cord and placenta essentially), abnormalities of gestation, maternal and foetal origins. Infectious abortions are caused in almost cases by bacterial infections, followed by viruses, fungi and parasites. New abortive pathogens (as Leptospira, Neospora caninum, Coxiella burnetii, Chlamydophila abortus, and) have been confirmed in equines by comparison alre...
Mousavi SF, Razmkabir M, Rostamzadeh J, Seyedabadi HR, Naboulsi R, Petersen JL, Lindgren G.Indigenous Iranian horse breeds were evolutionarily affected by natural and artificial selection in distinct phylogeographic clades, which shaped their genomes in several unique ways. The aims of this study were to evaluate the genetic diversity and genomewide selection signatures in four indigenous Iranian horse breeds. We evaluated 169 horses from Caspian (n = 21), Turkmen (n = 29), Kurdish (n = 67), and Persian Arabian (n = 52) populations, using genomewide genotyping data. The contemporary effective population sizes were 59, 98, 102, and 113 for Turkmen, Caspian, Persian Ar...
Tozaki T, Ohnuma A, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Takahashi Y, Nagata SI.Gene doping, which is prohibited in horseracing and equestrian sports, can be performed by introducing exogenous genes, known as transgenes, into the bodies of postnatal animals. To detect exogenous genes, a method utilizing quantitative polymerase chain reaction (qPCR) with a hydrolysis probe was developed to test whole blood and plasma samples, thereby protecting the fairness of competition and the rights of stakeholders in horseracing and equestrian sports. Therefore, we aimed to develop sample storage methods suitable for A and B samples in gene doping tests using blood. For sample A, suff...
Scalco R, de Oliveira GN, da Rosa Curcio B, Wooten M, Magdesian KG, Hidai ST, Pandit P, Aleman M.Rapid and accurate markers to aid diagnosis of sepsis are needed in neonatal foals. The CBC variable red blood cell distribution width (RDW) to platelet ratio (RPR) is associated with inflammatory response and linked to poor outcomes of sepsis in human patients. Objective: Explore the correlation of RPR with sepsis in neonatal foals and evaluate RPR predictive and prognostic value. Methods: Three hundred seventeen hospitalized neonatal foals ≤7 days of age that had a CBC and physical exam performed at admission between 2012 and 2021. Methods: Retrospective case-control study. Clinical reco...
Dolin A, Schweiger P, Waselau M, Egerbacher M, Walter I.Sex cord-stromal tumors (SCSTs), generally referred to as granulosa cell tumors (GCTs) or granulosa-theca cell tumors (GTCTs) in equids, show complex compositions and variable numbers of hormone-producing cells. These tumors can be difficult to diagnose, especially in early stages. Therefore, we tested a panel of antibodies for vimentin, smooth muscle actin, laminin, Ki-67, E-cadherin, calretinin, moesin, p-ezrin, AMH, and aromatase, markers used for tumor composition and classification, progression, and prognosis in human SCSTs, on an exemplary grapefruit-size equine GCT within the left ovary...
Akinniyi OO, Sackey AKB, Ochube GE, Mshelia PW, Musa FA, Elijah MO, Jolayemi KO.Insulin dysregulation (ID) is central to the pathophysiology of equine metabolic syndrome (EMS), putting the horse at risk of laminitis. There is a paucity of information on the status of EMS in Nigeria. This study aimed to determine the occurrence of EMS, clinical manifestations, and associated risk factors in Nigeria. A cross-sectional study was carried out. Selected horses underwent an insulin 2-step response test to ascertain insulin dysregulation; a physical examination was carried out to diagnose laminitis and obesity. Risk factors were assessed using a questionnaire. The overall prevale...
Kakoi H, Kikuchi M, Ishige T, Hirosawa Y, Tanaka S, Nagata SI.To confirm the positive conversion of antibodies against erythrocyte antigens in horses, possible blood transfusion donor horses selected from draft horse populations were periodically monitored with an indirect antiglobulin (Coombs) test for approximately 3 years. In this study, 19 horses (16 females and 3 males) were investigated, and five mares showed alloantibodies during the monitoring period. Four mares were typically pregnant when positive conversion was detected, whereas no particular cause of conversion could be observed for one mare based on its clinical records. In the analyzed hors...
Pye JL, Garcia TC, Kapatkin AS, Samol MA, Stover S.To compare (1) performance of compact versus standard flute drill bits, (2) screw insertion properties and (3) pullout variables between interlocking thread (ITS) and buttress thread (BTS) self-tapping screws in third metacarpi. Methods: In vitro experimental study. Methods: Paired third metacarpi from 11 Thoroughbreds aged 2-4 years. Methods: Screws were inserted into the lateral condylar fossae following bone preparation using the respective drill bit for each screw type. Screw pullout was achieved using a mechanical testing system. Density and porosity of bone surrounding screw holes was ...
Castro-Mesa AF, Resende Faleiros R, Martínez-Aranzales JR.Ultrasonography is commonly used to evaluate equine lameness-related structures, but traditional hoof approaches cannot adequately visualize internal structures such as the lamellar layer. To address this limitation, we used 62 healthy hooves without digital radiographic abnormalities, made up of thirty anatomical pieces (phase 1) and thirty-two hooves from living horses (phase 2). In both phases, half of the digits were submerged in water (group 1) and the other half in water and ice (group 2) for 24 h. Ultrasonographic views and temperature and humidity measurements were taken every two hour...
Mathewos M, Bukero R, Endale H, Mekbib B, Giday W, Mekore D.Epizootic lymphangitis is a contagious, chronic and overwhelming disease of equids, characterized by chronic discharging skin nodules. This study was aimed to investigate the prevalence and associated risk factors of epizootic lymphangitis in equines at Nagele Arsi town, southeastern Ethiopia. A cross-sectional study using a random sampling technique was employed from December 2021 to June 2022 via clinical and microscopic examinations of the lesions. The overall prevalence of epizootic lymphangitis was 4.37% with a prevalence of 6.69%, 0.72%, and 0% in horses, donkeys, and mules, respectively...
Tukia E, Hallman I, Penttilä M, Hänninen S, Kareskoski M.Endometritis is one of the major causes of infertility in mares. and -haemolytic streptococci are among the bacterial species most frequently isolated from the equine uterus. Some bacteria such as -hemolytic streptococci, can persist in dormant forms and cause prolonged, latent or recurrent infections. Dormant bacteria may be present despite negative bacterial cultures, and they are resistant to antimicrobial treatment due to their resting metabolic state. The purpose of this study was to study formalin-fixed paraffin-embedded equine endometrial biopsies for the presence and localization of -...
Dyson S, Pollard D.The Ridden Horse Pain Ethogram (RHpE) was developed to facilitate the recognition of musculoskeletal pain. The aim of this study was to document changes in RHpE scores before and after diagnostic anaesthesia was performed to alleviate pain ± when the saddle was changed. One hundred and fifty horses underwent ridden exercise as part of an investigation of poor performance. The RHpE was applied before and after the interventions. Fifty-two (34.7%) horses exhibited a bilaterally symmetrical short step length and/or restricted hindlimb impulsion and engagement. Fifty-three (35.3%) horses had epis...
Norton AM, McGilp D, Vasey JR.A 4-month old, 200 kg, grey warmblood colt presented for a firm, non painful mass on the distal medial aspect of the left third metatarsus. Excisional biopsy revealed a diagnosis of haemangiosarcoma. Equine haemangiosarcoma is uncommon and only limited reports of successful treatment are available. The prognosis for survival is therefore considered to be poor. After two separate incidences of recurrence with incomplete excision of the tumour, intralesional treatment with cisplatin without excision or debulking was performed on three separate occasions. Intralesional cisplatin injection was p...
Lorga AD, Gomes ARC, Strugava L, Moreno JCD, Dornbusch PT.Thoracoscopy pericardiotomy consists of endoscopic access to the thoracic cavity to perform the opening of the pericardial sac, described in the equine species only through the intercostal access, and there are no studies addressing the singleport transdiaphragmatic access, so the objective was to develop the pericardiotomy technique by transdiaphragmatic thoracoscopy using a single port. The technique was performed using six cadavers of adult horses, positioned in dorsal decubitus, making it possible to initiate access with an incision in the region proximal to the xiphoid process, for the in...
Valberg SJ, Williams ZJ, Henry ML, Finno CJ.Shivers in horses is characterized by abnormal hindlimb movement when walking backward and is proposed to be caused by a Purkinje cell (PC) axonopathy based on histopathology. Objective: Define region-specific differences in gene expression within the lateral cerebellar hemisphere and compare cerebellar protein expression between Shivers horses and controls. Methods: Case-control study of 5 Shivers and 4 control geldings ≥16.2 hands in height. Methods: Using spatial transcriptomics, gene expression was compared between Shivers and control horses in PC soma and lateral cerebellar hemisphere w...
Maniego J, Giles O, Hincks P, Stewart G, Proudman C, Ryder E.We present here the use of targeted, long-read sequencing of the myostatin (MSTN) gene as a model to detect potential gene editing events in Thoroughbred horses. MSTN is a negative regulator of muscle development, making the gene a prime candidate target for gene doping. By sequencing the complete gene in one PCR product, we can catalogue all mutations without the need to produce short-fragment libraries. A panel of reference material fragments with defined mutations was constructed and successfully sequenced by both Oxford Nanopore and Illumina-based methods, showing that gene doping editing ...
Batcher K, Varney S, Raudsepp T, Jevit M, Dickinson P, Jagannathan V, Leeb T, Bannasch D.LINE-1 is an active transposable element encoding proteins capable of inserting host gene retrocopies, resulting in retro-copy number variants (retroCNVs) between individuals. Here, we performed retroCNV discovery using 86 equids and identified 437 retrocopy insertions. Only 5 retroCNVs were shared between horses and other equids, indicating that the majority of retroCNVs inserted after the species diverged. A large number (17-35 copies) of segmentally duplicated Ligand Dependent Nuclear Receptor Corepressor Like (LCORL) retrocopies were present in all equids but absent from other extant peris...
Dash RF, Minshall GJ, Wright IM.Slab fractures of the third carpal bone (C3) are a common cause of lameness in Thoroughbred racehorses. Information on fracture morphology is commonly obtained from radiographs or CT. This retrospective, methods comparison aimed to explore the agreement between radiography and CT for imaging C3 slab fractures and discuss the contribution of the latter to clinical case management. Thoroughbred racehorses with a slab or incomplete slab fracture of C3 identified on radiographs that subsequently underwent CT examination were included. Fracture characteristics (location, plane, classification, disp...
Ferreira LVO, Kamura BDC, Oliveira JPM, Chimenes ND, Carvalho M, Santos LAD, Dias-Melicio LA, Amorim RL, Amorim RM.Schwann cells (SCs) are essential for the regenerative processes of peripheral nerve injuries. However, their use in cell therapy is limited. In this context, several studies have demonstrated the ability of mesenchymal stem cells (MSCs) to transdifferentiate into Schwann-like cells (SLCs) using chemical protocols or co-culture with SCs. Here, we describe for the first time the in vitro transdifferentiation potential of MSCs derived from equine adipose tissue (AT) and equine bone marrow (BM) into SLCs using a practical method. In this study, the facial nerve of a horse was collected, cut into ...
Benvin I, Perko VM, Maljković MM, Habuš J, Štritof Z, Hađina S, Perharić M, Zečević I, Cvetnić M, Turk N.Leptospirosis is re-emerging zoonotic bacterial disease of global importance that affects domestic and wild animals and humans. Due to the public health importance, control of disease in Croatia is being implemented by monitoring the seroprevalence of equine leptospirosis and it is regulated by the law. In the period from 2012 to 2022, a total of 61,724 serum samples from apparently healthy horses were admitted to the Laboratory for leptospires, Faculty of Veterinary Medicine University of Zagreb. Serum samples were tested for Leptospira spp. antibodies using the microscopic agglutination test...
Higgins C, Huber L.Rhodococcus equi, a gram-positive facultative intracellular pathogen and a soil saprophyte, is one of the most common causes of pneumonia in young foals. It poses a threat to the economy in endemic horse-breeding farms and to animal welfare annually. Many farms use thoracic ultrasonographic screening and antimicrobial treatment of subclinically affected foals as a preventive measure against severe R. equi infections. The wide use antimicrobials to treat subclinically affected foals has contributed to the emergence of multidrug resistant (MDR)-R. equi in both clinical isolates from sick foals a...
Mercer MA, Davis JL, McKenzie HC, Byron CR, Kelleher ME, Trager L, Cecere TE, Wilson KE, Council-Troche RM, Werre SR.Acetaminophen is used clinically in horses with musculoskeletal pain; however, no studies have been performed in horses with chronic lameness. Objective: To determine the pharmacokinetics, safety and efficacy of chronic dosing of acetaminophen in horses with naturally occurring chronic lameness. Methods: Longitudinal. Methods: Twelve adult horses with chronic lameness were treated with acetaminophen (30 mg/kg PO) every 12 h for 21 days. Plasma concentrations of acetaminophen were analysed on days 7 and 21 via LC-MS/MS and noncompartmental pharmacokinetic analysis. Lameness was evaluated ...
Saklou N, Pleasant S, Lahmers K, Funk R.Equine Herpesvirus type 1 (EHV-1) typically causes mild respiratory disease, but it can also cause late-term abortion, neonatal foal death and neurologic disease. Once a horse is infected, the virus concentrates to local lymphoid tissue, where it becomes latent. The virus can be reactivated during times of stress, which can lead to the initiation of devastating outbreaks. Understanding the carriage rate of latent EHV-1 in different geographic regions is essential for managing the disease. The objective of the current study was to estimate the prevalence of latent EHV-1 and compare the frequenc...
Faulkner JE, Broeckx BJG, Martens A, Raes E, Haardt H, Vanderperren K.Metal artifacts in CT negatively impact the evaluation of surgical implants and the surrounding tissues. The aim of this prospective experimental study was to evaluate the ability of a single energy metal artifact reduction (SEMAR™, Canon) algorithm and virtual monoenergetic (VM) dual-energy CT (DECT) scanning techniques to reduce metal artifacts from stainless steel screws surgically inserted into the equine proximal phalanx. Seven acquisitions of 18 cadaver limbs were performed on a Canon Aquilion One Vision CT scanner (Helical +SEMAR, Volume +SEMAR, Standard Helical, Standard Volume and V...
Melzer M, Burk J, Guest DJ, Dudhia J.Mesenchymal stromal cells (MSC) isolated form bone marrow and adipose tissue are the most common cells used for cell therapy of orthopedic diseases. MSC derived from different tissues show differences in terms of their proliferation, differentiation potential and viability in prolonged cell culture. This suggests that there may be subtle differences in intracellular signaling pathways that modulate these cellular characteristics. The Rho/ROCK signaling pathway is essential for many cellular functions. Targeting of this pathway by the ROCK inhibitor Y-27632 has been shown to be beneficial for c...
Foth PW, Gardner A, Pereira CR, Cooper E, Schroeder E, Mudge MC.To assess oral buccal microcirculation by hand-held videomicroscopy in horses during colic surgery, comparing microcirculation values with macrocirculatory parameters and with those of healthy elective surgical horses. Methods: Clinical prospective study. Methods: Client-owned horses (nine in the colic group; 11 in the elective group). Methods: In the colic group, buccal mucosal side stream dark-field microscopy (DFM) videos, cardiac output (CO), mean arterial pressure (MAP), and lactate were obtained at three timepoints under general anesthesia (30, 90, and 150 min after induction). Video a...
Young N, Barker W, Minshall G, Wright I.To describe an arthroscopically guided technique for lag screw placement across subchondral bone cyst (SBC) in the medial femoral condyle (MFC) and to compare postoperative racing performance with corticosteroid injection and cyst debridement. Methods: Retrospective cohort study. Methods: One hundred twenty-three horses with 134 MFC SBCs undergoing treatment at a single referral hospital in the UK between January, 2009, and December, 2020. Methods: Sex, age, limb affected, radiographic cyst dimensions, preoperative and postoperative lameness, surgical technique (lag screw placement, cyst debr...
Kilcoyne I, Nieto J, Magdesian KG, Nottle BF.To determine the effect of a 10% dimethyl sulfoxide (DMSO) solution on the peak concentration (C ) of amikacin in the radiocarpal joint (RCJ) during intravenous regional limb perfusion (IVRLP) compared with 0.9% NaCl. Methods: Randomized crossover study. Methods: Seven healthy adult horses. Methods: The horses underwent IVRLP with 2 g of amikacin sulfate diluted to 60 mL using a 10% DMSO or 0.9% NaCl solution. Synovial fluid was collected from the RCJ at 5, 10, 15, 20, 25, and 30 minutes after IVRLP. The wide rubber tourniquet placed on the antebrachium was removed after the 30 min sample. A...
Szóstek-Mioduchowska AZ, Baclawska A, Okuda K, Skarzynski DJ.Equine endometrosis (endometrial fibrosis) is a degenerative chronic process that occurs in the uterus of the mare and disturbs proper endometrial function. Fibrosis is attributed to excessive deposition of extracellular matrix (ECM) components. The turnover of ECM is mediated by matrix metallopeptidases (MMP). Previously, it was shown that cytokines modulate MMP expression in other tissues and may regulate fibrosis indirectly by attracting inflammatory cells to the site of inflammation and directly on various tissues. However, the regulation of MMP expression in equine endometrosis is still r...
Irvine KL, Hopkins LJ, Gangloff M, Bryant CE.TLR2 recognises bacterial lipopeptides and lipoteichoic acid, and forms heterodimers with TLR1 or TLR6. TLR2 is relatively well characterised in mice and humans, with published crystal structures of human TLR2/1/Pam3CSK4 and murine TLR2/6/Pam2CSK4. Equine TLR4 is activated by a different panel of ligands to human and murine TLR4, but less is known about species differences at TLR2. We therefore cloned equine TLR2, TLR1 and TLR6, which showed over 80% sequence identity with these receptors from other mammals, and performed a structure-function analysis. TLR2/1 and TLR2/6 from both horses and hu...
Vázquez-Morón S, Avellón A, Echevarría JE.The Lyssavirus genus includes seven species or genotypes named 1-7. Rabies genotypes correlate with geographical distribution and specific hosts. Co-circulation of different lyssaviruses, imported cases, and the presence of unknown viruses, such as Aravan, Khujand, Irkut and West Caucasian Bat Virus, make it necessary to use generic methods able to detect all lyssaviruses. Primer sequences were chosen from conserved regions in all genotypes in order to optimise a generic RT-PCR. Serial dilutions of 12 RNA extracts from all seven Lyssavirus genotypes were examined to compare the sensitivity of ...
Franchini M, Gill U, von Fellenberg R, Bracher VD.To analyze effects of hay dust exposure on interleukin-8 (IL-8) concentration, percentage of neutrophils, and neutrophil chemotactic activity in bronchoalveolar lavage fluid (BALF) of horses with chronic obstructive pulmonary disease (COPD). Methods: 16 healthy horses and 29 horses with COPD. Methods: IL-8 concentration, percentage of neutrophils, and neutrophil chemotactic activity in BALF were measured. Values were analyzed with respect to hay dust exposure. These variables were also measured in 5 asymptomatic horses with COPD after the induction of clinical signs by changing feed from silag...
Song SD, Barker SC, Shao R.The genus Haematopinus contains 21 species of blood-sucking lice, parasitizing both even-toed ungulates (pigs, cattle, buffalo, antelopes, camels and deer) and odd-toed ungulates (horses, donkeys and zebras). The mitochondrial genomes of the domestic pig louse, Haematopinus suis, and the wild pig louse, Haematopinus apri, have been sequenced recently; both lice have fragmented mitochondrial genomes with 37 genes on nine minichromosomes. To understand whether the composition of mitochondrial minichromosomes and the gene content and gene arrangement of each minichromosome are stable within the g...
Imai DM, Barr BC, Daft B, Bertone JJ, Feng S, Hodzic E, Johnston JM, Olsen KJ, Barthold SW.Lyme neuroborreliosis--characterized as chronic, necrosuppurative to nonsuppurative, perivascular to diffuse meningoradiculoneuritis--was diagnosed in 2 horses with progressive neurologic disease. In 1 horse, Borrelia burgdorferi sensu stricto was identified by polymerase chain reaction amplification of B burgdorferi sensu stricto-specific gene targets (ospA, ospC, flaB, dbpA, arp). Highest spirochetal burdens were in tissues with inflammation, including spinal cord, muscle, and joint capsule. Sequence analysis of ospA, ospC, and flaB revealed 99.9% sequence identity to the respective genes in...
Mares-Guia MA, Rozental T, Guterres A, Gomes R, Almeida DN, Moreira NS, Barreira JD, Favacho AR, Santana AL, Lemos ER.Over the last recent years, the number of Q fever cases have has increased throughout the world. An epidemiological investigation was performed in the area in which the first molecular documentation of Q fever in Brazil was previously reported. Methods: Indirect immunofluorescence assay (IFA) and PCR of Coxiella burnetii targeting the htpAB gene were performed in samples from 14 dogs (blood); 1 cat (blood); 10 goats (blood, milk, vaginal swab and anal swab); 3 sheep (blood); and 2 horses (blood). Results: Two dogs, two sheep and five goats were seroreactive. DNA was amplified from 6 milk and 2...
Donadeu FX, Schauer SN.Relatively little is known about the physiological roles of microRNAs (miRNAs) during follicular development. Previous evidence from in vitro studies suggests specific roles for a subset of miRNAs, including miR-21, miR-23a, miR-145, miR-503, miR-224, miR-383, miR-378, miR-132, and miR-212, in regulating ovarian follicle development. The objective of this study was to gain insight on the involvement of these miRNAs during follicle maturation. Follicular fluid was aspirated from dominant follicles (>32 mm) during the ovulatory season (July to October) and the anovulatory season (January to M...
Simon EL, Gaughan EM, Epp T, Spire M.To determine the amount of time required for surface temperatures of thoracic and pelvic limbs in horses to return to pre-exercise temperatures after high-speed treadmill exercise, as detected via infrared thermographic imaging. Methods: Prospective study. Methods: 6 Thoroughbreds. Methods: All horses had been trained on and conditioned to use of a high-speed treadmill. Baseline thermographic images were obtained 3 days prior to exercise (baseline). Horses were exercised on a treadmill at a walk for 5 minutes, a slow trot (3 m/s) for 5 minutes, a trot (5 to 6 m/s) for 5 minutes, and a slow gal...
Leblond A, Pradier S, Pitel PH, Fortier G, Boireau P, Chadoeuf J, Sabatier P.Anaplasmosis is caused by the bacterium Anaplasma phagocytophilum and transmitted by Ixodes spp. ticks. According to some reports the disease can be introduced into disease-free zones by migrating birds. The purpose of this study was to evaluate the seroprevalence of A. phagocytophilum in horses in the Camargue. Data concerning 424 horses were gathered and the sera were tested for A. phagocytophilum and for piroplasmoses using an enzyme-linked immunosorbent assay and a complement fixation test, respectively. The seroprevalence rates were 11.3 % for A. phagocytophilum, 64.4 % for Theileria equi...
Boyko AR, Brooks SA, Behan-Braman A, Castelhano M, Corey E, Oliveira KC, Swinburne JE, Todhunter RJ, Zhang Z, Ainsworth DM, Robinson NE.Equine recurrent laryngeal neuropathy (RLN) is a bilateral mononeuropathy with an unknown pathogenesis that significantly affects performance in Thoroughbreds. A genetic contribution to the pathogenesis of RLN is suggested by the higher prevalence of the condition in offspring of RLN-affected than unaffected stallions. To better understand RLN pathogenesis and its genetic basis, we performed a genome-wide association (GWAS) of 282 RLN-affected and 268 control Thoroughbreds. Results: We found a significant association of RLN with the LCORL/NCAPG locus on ECA3 previously shown to affect body siz...
Townsend HG, Leach DH.The anatomical features of 21 equine thoracolumbar spines, obtained from horses with clinically normal backs, were examined and the results compared with recent data on the mobility of the joint complexes of the horse's spine. The thoracolumbar spine can be divided into four regions based upon the morphology of the joint complexes: the first thoracic intervertebral joint (T1-2), the cranial and mid thoracic region (T2-T16), the caudal thoracic and lumbar region (T16-L6) and the lumbosacral joint. The mobility of the intervertebral joints in each of these regions can be related to their morphol...
Johnson PJ, Wiedmeyer CE, Messer NT, Ganjam VK.There is growing recognition that obesity is common and represents a significant detriment to the health of companion animals in a manner similar to that by which it is affecting the human population. As is the case for other species, obesity appears to promote insulin resistance in horses and it is through this pathophysiological process that many of the adverse medical consequences of obesity are being characterized. Equine medical conditions that have been described in the context of obesity and insulin resistance differ from those in humans. Chronic human conditions that have been attribut...
Paillot R, Kydd JH, Sindle T, Hannant D, Edlund Toulemonde C, Audonnet JC, Minke JM, Daly JM.In horses, equine influenza virus (EIV) is a leading cause of respiratory disease. Conventional inactivated vaccines induce a short-lived immune response. By comparison, natural infection confers a long-term immunity to re-infection. An aim of new equine influenza vaccines is to more closely mimic natural infection in order to achieve a better quality of immunity. A new live recombinant vaccine derived from the canarypox virus vector and expressing haemagglutinin genes of EIV (subtype H3N8) has been developed. Stimulation of the immune system was studied after immunisation with this canarypox-...
van Loon JPAM, Macri L.The objective assessment of chronic pain is of utmost importance for improving welfare and quality of life in horses. Freedom from disease and pain is one of the 'five freedoms' that are necessary for animal welfare. The aim of this study was to develop a pain scale for the assessment of chronic pain in horses (Horse Chronic Pain Scale; HCPS), which is based on behavioural and facial expressions. The scale was used to assess 53 horses (26 horses diagnosed with chronic painful conditions by means of clinical examination and additional diagnostic procedures (consisting of osteoarthritis, chronic...
Raabe ML, Issel CJ, Cook SJ, Cook RF, Woodson B, Montelaro RC.We have previously reported that immunization of ponies with a baculovirus-expressed recombinant surface unit envelope protein (rgp90) for equine infectious anemia virus (EIAV) resulted in enhancement of disease symptoms and virus replication in 4 of 4 vaccine recipients subjected to a heterologous virus challenge (rpg90 I vaccine trial) (Wang et al., 1994). To extend these studies of EIAV vaccine enhancement, two additional and independent rgp90 vaccine trials (rgp90 II and rgp90 III) were performed. Combined, a total of 13 ponies were immunized with the rgp90 immunogen using our standard vac...
Gilger BC, Salmon JH, Wilkie DA, Cruysberg LP, Kim J, Hayat M, Kim H, Kim S, Yuan P, Lee SS, Harrington SM, Murray PR, Edelhauser HF, Csaky KG....To determine the feasibility, safety, and effectiveness of an episcleral or deep scleral lamellar sustained release cyclosporine (CsA) device in a naturally occurring animal model of uveitis. Methods: A two-compartment perfusion chamber was used to assess in vitro human and equine scleral permeability of fluorescein, dexamethasone-fluorescein, or CsA. A biodegradable, matrix-reservoir CsA implant was designed, and release rates of CsA were determined in vitro. Tissue CsA levels were measured in eyes with the implant. Horses with equine recurrent uveitis (ERU) received episcleral or deep sclera...
Habacher G, Pittler MH, Ernst E.Acupuncture is a popular complementary treatment option in human medicine. Increasingly, owners also seek acupuncture for their animals. The aim of the systematic review reported here was to summarize and assess the clinical evidence for or against the effectiveness of acupuncture in veterinary medicine. Systematic searches were conducted on Medline, Embase, Amed, Cinahl, Japana Centra Revuo Medicina and Chikusan Bunken Kensaku. Hand-searches included conference proceedings, bibliographies, and contact with experts and veterinary acupuncture associations. There were no restrictions regarding t...
Blanchard-Channell M, Moore PF, Stott JL.Two monoclonal antibodies (mAb), UC F6G-3 and UC F13C-5, were characterized as being specific for the apparent equine homologues of CD3 and CD5, respectively. Both antibodies exhibited characteristics of pan-T-lymphocyte markers based upon immunohistology and two-colour flow cytometry. UC F6G-3 precipitated a complex of proteins (up to seven) with molecular weights ranging from 18,000 to 42,000, similar to the human and murine CD3 complex. Upon further dissociation of the precipitated complex, two proteins were identified with molecular weights of 22,000 and 27,000. Immobilized UC F6G-3 was ef...
Riesenberg A, Feßler AT, Erol E, Prenger-Berninghoff E, Stamm I, Böse R, Heusinger A, Klarmann D, Werckenthin C, Schwarz S.The aim of this study was to determine the MICs of 32 antimicrobial agents for 200 isolates of Rhodococcus equi of animal origin by applying a recently described broth microdilution protocol, and to investigate isolates with distinctly elevated rifampicin MICs for the genetic basis of rifampicin resistance. Methods: The study included 200 R. equi isolates, including 160 isolates from horses and 40 isolates from other animal sources, from the USA and Europe. MIC testing of 32 antimicrobial agents or combinations thereof followed a recently published protocol. A novel PCR protocol for the joint ...
Haussler KK.The clinical assessment of pain is subjective; therefore, variations exist between practitioners in their ability to identify and localize pain. Due to differing interpretations of the signs or severity of pain equine practitioners may assign varying levels of clinical significance and treatment options. There is a critical need to develop better tools to qualify and quantify pain in horses. Palpation is the most common method to detect local tenderness or sensitivity. To quantify this applied pressure, pressure algometry has been used to gradually apply pressure over specified landmarks until...
Collins P.In vitro sensitivity data suggest that acyclovir should be effective against clinical manifestations of herpes simplex virus types 1 and 2, varicella-zoster virus and possibly Epstein-Barr virus. The clinical potential against herpes simplex virus types 1 and 2 is further supported by results in animal models. Human cytomegalovirus and the veterinary herpes viruses, with the possible exception of equine herpes virus type 1, may be insufficiently sensitive to be amenable to treatment.
Martin RB, Lau ST, Mathews PV, Gibson VA, Stover SM.We studied birefringence as an indicator of collagen fiber orientation in the diaphysis of the equine third metacarpal bone. We had previously shown that tissue from the lateral cortex of this bone is stronger monotonically, but less fatigue resistant, than tissue from the medial and dorsal regions. To learn whether collagen fiber orientation might play a role in this regional specialization, we tested three hypotheses using the same specimens: (1) collagen fiber orientation is regionally dependent; (2) remodeling changes collagen fiber orientation; (3) longitudinal collagen fibers correlate p...
Wennerstrand J, Johnston C, Roethlisberger-Holm K, Erichsen C, Eksell P, Drevemo S.Earlier studies have developed a clinical tool to evaluate objectively the function of the equine back. The ability to differentiate horses with back pain from asymptomatic, fully functioning horses using kinematic measures from this tool has not been evaluated. Objective: To compare the kinematics of the back at walk and trot in riding horses with back dysfunction to the same parameters in asymptomatic sport horses. Methods: The kinematics of the back in 12 horses with impaired performance and back pain were studied at walk and trot on a treadmill. Data were captured for 10 sees at 240 Hz. Ra...
Brownlow MA, Dart AJ, Jeffcott LB.Metabolic heat produced by Thoroughbred racehorses during racing can rapidly elevate core body temperature (1°C/min). When environmental conditions are hot and humid, the normal physiological cooling mechanisms become ineffective. The heat accumulated may exceed a critical thermal maximum (estimated to be 42°C), which may trigger a complex pathophysiological cascade with potentially lethal consequences. This syndrome has been labelled exertional heat illness (EHI). EHI is described in humans, but has not been well documented in Thoroughbred racehorses. The clinical signs described in racehor...
Roth D, Henry B, Mak S, Fraser M, Taylor M, Li M, Cooper K, Furnell A, Wong Q, Morshed M.In 2009, an expansion of West Nile virus (WNV) into the Canadian province of British Columbia was detected. Two locally acquired cases of infection in humans and 3 cases of infection in horses were detected by ELISA and plaque-reduction neutralization tests. Ten positive mosquito pools were detected by reverse transcription PCR. Most WNV activity in British Columbia in 2009 occurred in the hot and dry southern Okanagan Valley. Virus establishment and amplification in this region was likely facilitated by above average nightly temperatures and a rapid accumulation of degree-days in late summer....
Leise BS, Faleiros RR, Watts M, Johnson PJ, Black SJ, Belknap JK.There is a need to assess the laminar inflammatory response in a laminitis model that more closely resembles clinical cases of sepsis-related laminitis than the black walnut extract (BWE) model. Objective: To determine if a similar pattern of laminar inflammation, characterised by proinflammatory cytokine expression, occurs in the CHO model of laminitis as has been previously reported for the BWE model. Methods: Sixteen horses administered 17.6 g of starch (85% corn starch/15% wood flour)/kg bwt via nasogastric (NG) tube were anaesthetised either after developing a temperature>38.9°C (DEV ...
