Equine diseases encompass a wide range of health conditions that can affect horses, including infectious diseases, metabolic disorders, and genetic conditions. These diseases can impact the overall health, performance, and well-being of horses. Common equine diseases include equine influenza, equine herpesvirus, laminitis, and equine metabolic syndrome. Diagnosis and management of these diseases often require a combination of clinical evaluation, laboratory testing, and appropriate treatment strategies. This page gathers peer-reviewed research studies and scholarly articles that explore the etiology, pathophysiology, diagnosis, and treatment options for various equine diseases, providing valuable insights for veterinarians and researchers in the field.
Baldani CD, Hilario E, Nakaghi AC, Bertolini MC, Machado RZ.The erythrocytic-stage surface protein, Equi Merozoite Antigen 1 (EMA-1), is a major candidate for the development of a diagnostic antigen for equine piroplasmosis. In order to establish an effective diagnostic method for practical use, the gene encoding the entire EMA-1 of Theileria equi Jaboticabal strain was cloned and expressed in Escherichia coli as a histidine-tagged protein (His6-EMA1). The expressed EMA-1 reacted with specific antibodies in Western blot and had an apparent molecular mass of 34 kDa which was largely consistent with its theoretical value. The nucleotide sequence of the E...
Ataseven VS, Oğuzoğlu TÇ, Başaran-Karapınar Z, Bilge-Dağalp S.Equine adenovirus type 1 (EAdV-1) is a cause of repiratory tract infection in equids. In present study for the first time in Turkey, the prevalence of EAdV-1 in nasal swab samples obtained from horses showing respiratory symptoms was investigated by polymerase chain reaction (PCR), and molecular characterization of the hexon gene detected in the Turkish (TR) strain was performed. Overall, the prevalence of EAdV-1 was found low (1.4%) as indicated by a positive PCR reaction from the nasal swab extracts tested. Phylogenetic analysis based on the partial sequences of the hexon gene of a TR-EAdV-1...
García BM, Moran AM, Fernández LG, Ferrusola CO, Rodriguez AM, Bolaños JM, da Silva CM, Martínez HR, Tapia JA, Peña FJ.Cryopreservation introduces extreme temperature and osmolality changes that impart lethal and sublethal effects on spermatozoa. Additionally, there is evidence that the osmotic stress induced by cryopreservation causes oxidative stress to spermatozoa. The main sources of reactive oxygen species in mammalian sperm are the mitochondria. In view of this, the aim of our study was to test whether or not osmotic stress was able to induce mitochondrial damage and to explore the osmotic tolerance of the mitochondria of stallion spermatozoa. Ejaculates from 7 stallions were subjected to osmolalities ra...
Spirito S, Campi S, Boquet M, Fernández H, Ferrari M.The aims of this study were to estimate the ability of the Feulgen reaction to identify equine sperm nuclei with different ploidy levels, to determine the frequency of haploid, diploid and polyploid sperm nuclei in the semen of fertile equines and to evaluate the relationship between the nuclear DNA content and the nuclear area. Determination of the ploidy level of Feulgen-stained spermatozoa using a scanning microspectrophotometer was very similar to the subjective estimations made with a light microscope. This indicates that the Feulgen reaction is a simple, inexpensive and reliable techniqu...
Watts AE, Johnson AL, Felippe MJ, Divers TJ.A Thoroughbred gelding in North America was evaluated for Actinobacillus peritonitis on three different occasions over a 4-year period. At each presentation, peritoneal fluid had an elevated nucleated cell count (220,000-550,000 cells/µL) characterised by non-degenerate neutrophils, no visible bacteria, an elevated total protein (4.6-5.5 g/dL) and bacterial culture yielding Actinobacillus spp. Actinobacillus peritonitis appears to be a regional disease occurring in Australia and less commonly in New Zealand and North America. Recurrence, other than incomplete resolution, has not been previous...
Abdel-Moneim AS, Shehab GM, Abu-Elsaad AA.Phylogenetic and evolutionary patterns of the six internal genes of an equine H5N1 influenza A virus isolated in Egypt on 2009 were analyzed using direct sequencing. All of the internal genes of the equine H5N1 strain showed a genetic pattern potentially related to Eurasian lineages. Variable dendrogram topologies revealed an absence of reassortment in the equine strain while confirming its close relatedness to other Egyptian H5N1 strains from human and avian species. The equine strain is characterized by a variety of amino acid substitutions in six internal proteins compared to the available ...
Rottensteiner U, Palm F, Kofler J.The purpose of this study was to map the coxofemoral region in foals to obtain ultrasonographic reference values for the interpretation of potentially pathological findings in hip joints. Using a 7.5 MHz linear transducer, 38 examinations were carried out: 10 (20 joints) on cadavers and 28 (55 joints) on live healthy foals up to 8 weeks of age. The chosen plane of examination was caudolateral-craniomedial oblique on an imaginary line connecting the greater trochanter and the cranial edge of the tuber sacrale. The relatively thin muscular layer covering the coxofemoral joint allowed good image ...
de Laat MA, van Eps AW, McGowan CM, Sillence MN, Pollitt CC.Laminitis has many triggers and comparing the histopathology of lesions induced by different causes may help to establish whether a common mechanism or multiple pathologies are involved. The aim of this study was to describe the microscopical lesions and to quantify morphometric changes in the lamellae of horses with insulin-induced (n=4) and oligofructose (OF)-induced laminitis (n=4) compared with normal controls (n=4). Archived lamellar samples collected during two previous studies were used. Laminitis was induced within 48 h in standardbred horses with either a euglycaemic, hyperinsulinaemi...
Hobson-Peters J, Arévalo C, Cheah WY, Blitvich BJ, Tan CS, Sandis A, Araya LN, Hernández JL, Toye P, Hall RA.We conducted a serosurvey for West Nile virus (WNV) infection in equines in Costa Rica in 2004. Antibodies to WNV were detected in 28% of the horses using an epitope blocking ELISA that is specific for WNV. WNV infection was confirmed for a subset of these sera by plaque reduction neutralization tests and Western blot. This is the first evidence of WNV activity in Costa Rica.
Burns TA, Westerman T, Nuovo GJ, Watts MR, Pettigrew A, Yin C, Belknap JK.Oxidative stress reportedly plays a role in sepsis-induced organ dysfunction and failure in many species. In septic horses, laminae are targeted; evidence of laminar oxidative stress has been reported experimentally in the black walnut extract (BWE) model. Carbohydrate (CHO)-induced laminitis may be more similar to clinical sepsis-related laminitis than the BWE model in that animals with CHO-induced disease commonly develop laminar failure. The role of oxidative stress in the CHO model remains unknown. Objective: Markers of oxidative stress will be increased in laminae from horses with BWE- an...
Gildea S, Arkins S, Walsh C, Cullinane A.Protection against equine influenza virus (EIV) relies largely on the production of circulating antibodies specific for the haemagglutinin (HA) glycoprotein. The objective of this study was to determine the antibody response of National Hunt horses in training to booster vaccination. The antibody response to the six equine influenza vaccines available in Ireland (three whole inactivated vaccines, two subunit vaccines and a canary pox recombinant vaccine), was monitored by single radial haemolysis (SRH) for six months post vaccination. There was no significant difference between antibody respon...
Broaddus CC, Balasuriya UB, White JL, Timoney PJ, Funk RA, Holyoak GR.To determine whether it is safe to vaccinate pregnant or postpartum mares with a commercial modified-live virus vaccine against equine viral arteritis (EVA). Design-Randomized controlled study. Animals-73 mares and their foals. Methods: Mares were vaccinated during mid gestation, during late gestation, or 2 or 3 days after parturition with a commercial modified-live virus vaccine or were not vaccinated. Foaling outcomes were recorded, and serum, blood, milk, and nasopharyngeal samples were obtained. Results: All mares vaccinated during mid gestation foaled without any problems; 21 of 22 mares ...
Costa MF, Davies HM, Anderson GA, Slocombe RF.Studies in man have shown a correlation between Angiotensin I-converting enzyme (ACE) genetic polymorphisms, ACE activity in the blood and superior athletic performance in sports requiring endurance. It has been hypothesised that the same correlation occurs in horses. There is no information in the literature concerning the effects of training on ACE activity in equine plasma. Objective: Exercise training influences the activity of circulating ACE and the response observed is dependent on the exercise protocol. Methods: Thirteen horses of mixed breeds were randomly allocated 2 different traini...
Venugopal CS, Eades S, Holmes EP, Beadle RE.One of the causes of equine laminitis is hyperinsulinaemia, which may be associated with endothelial dysfunction and insulin resistance of vessels. Objective: Insulin resistance can be induced in palmar digital vessels by continued exposure to insulin in vitro. The objective was to evaluate this in vitro model for future studies. Methods: Palmar digital vessel segments were collected immediately after euthanasia from horses with normal insulin/glucose blood values. Four arterial and 4 venous rings (3 mm wide) were prepared and each ring mounted in a tissue bath, containing Tyrode's solution at...
Brault LS, Penedo MC.A putative mutation causative of cerebellar abiotrophy (CA), a genetic defect found almost exclusively in Arabian horses, was recently identified. Objective: To investigate the presence of the CA mutation in breeds other than Arabian and ascertain whether the mutation had been introduced into these breeds by Arabian ancestry. The CA mutation is present in breeds of horses with Arabian ancestry. Methods: Allele-specific PCR was used to genotype 1845 non-Arabian horses for the CA mutation. For those breeds in which at least one carrier was identified, an additional 266 horses were genotyped to d...
Stubbs NC, Kaiser LJ, Hauptman J, Clayton HM.In human subjects with back pain, the deep spinal stabiliser m. multifidus is inhibited ipsilaterally leading to atrophy, asymmetry and intervertebral instability. Specific physiotherapeutic exercises are required to reactivate m. multifidus. This study assesses the effect of dynamic mobilisation exercises on size and symmetry of m. multifidus in the equine caudal thoracic and lumbar spine. Objective: Regular performance of dynamic mobilisation exercises over a period of 3 months increases cross sectional area (CSA) and left-right symmetry of m. multifidus muscles in the caudal thoracic and lu...
Cardwell JM, Wood JL, Smith KC, Newton JR.Rates of airway inflammation in young racehorses decrease with time but it is not clear whether this is associated with increasing age or time exposed to the training environment. The structure of the British National Hunt (NH) population allowed closer examination of this relationship. Objective: To compare rates of inflammatory airway disease diagnosed by tracheal sampling (trIAD), and its components, in NH racehorses by age and training history and with published rates in young racehorses. Methods: A prospective, longitudinal study was conducted on 5 NH yards over 2 years. Period sample pre...
Keller MD, Pollitt CC, Marx UC.NMR-metabonomics is an unbiased evaluation method, which allows to comprehensively study changes of the equine metabolic profile in early time point laminitis. This might give insight into the early stages of disease development. Objective: To detect hitherto unknown changes in blood metabolites during the development of oligofructose-induced laminitis by comparing pre- and post induction blood samples. Methods: Prior to laminitis induction blood was sampled to establish control values. Post oligofructose administration (POA) blood was collected every 3 h for 24 h. One-dimensional (1) H-NMR sp...
Liu Y, Uboh CE, Soma LR, Li X, Guan F, You Y, Rudy JA, Chen JW.Gabapentin (GPT) is an antiepileptic drug that was approved in 1993 for use in the management of neurotrophic pain and as an adjunctive therapy for refractory partial seizure in humans. It is also being tested in veterinary medicine as an adjunctive medication in the treatment of pain due to laminitis, neuropathic, or chronic pain. Gabapentin is readily available by prescription and even on the internet; therefore, it has the potential of being used in racehorses to mask pain. It is for this reason that a sensitive liquid chromatography-tandem mass spectrometry method has now been developed fo...
Faramarzi B.Hoof health is a major concern of horse owners as well as the equine industry. However, many questions remain concerning regional variations of laminar junction and its potential to remodel. Objective: To examine regional variations in the morphology of the laminar junction and thickness of the hoof wall in Thoroughbred horses. Methods: The forefeet of 25 Thoroughbred cadavers were examined. Each hoof was divided into 20 blocks through 4 proximodistal slices (below the coronary band, each 1 cm apart) and 5 circumferential positions (toe, medial and lateral quarters and heels). In each block, 2...
Hudgens E, Tompkins D, Boyd P, Lunney JK, Horohov D, Baldwin CL.This report describes the cloning and characterization of expressed gene sequences of bovine, equine, and swine CXCL9 from RNA obtained from peripheral blood mononuclear cells (PBMC) and other tissues. The bovine coding region was 378 nucleotides in length, while the equine and swine coding regions were 381 nucleotides. Mapping showed that all three sequences were coded for in four exons in the genome, as are the human and mouse genes. The bovine, equine, and swine coding regions shared 83%, 86%, and 84% homology with human CXCL9, respectively, and all three were 74% homologous with mouse CXCL...
Toribio RE.Calcium and phosphate have structural and nonstructural functions, and their concentrations in the extracellular compartment are affected by the physiologic status of the animal as well as diseases. Important progress in understanding calcium and phosphorus metabolism in healthy and diseased horses and foals has been made in recent years. For example, several studies have confirmed that hypocalcemia is frequent in horses with gastrointestinal disease and that calcium endocrine dysregulation is associated with survival in foals. One critical point in the homeostasis of these minerals is their i...
Frank N.The concept of an equine metabolic syndrome (EMS) was first proposed in 2002. This concept has developed over time, and EMS was recently described in a consensus statement released by the American College of Veterinary Internal Medicine. In human medicine, metabolic syndrome (MetS) refers to a set of risk factors that predict the risk of cardiovascular disease, including obesity, glucose intolerance and insulin resistance (IR), dyslipidemia, microalbuminuria, and hypertension. EMS shares some of the features of MetS, including increased adiposity, hyperinsulinemia, IR, but differs in that lami...
Barsnick RJ, Toribio RE.Hormonal control of energy metabolism plays an important role in the peripartum development and health of the equine neonate. The endocrine system is generally functional at birth, but the maturation of the endocrine system and the associated energy metabolism is delayed and continues during the postnatal period. The energy metabolism is susceptible to disturbances, especially when illness occurs. Hormones involved in energy metabolism have recently been studied in healthy and critically ill neonatal foals. Understanding these hormones in the equine neonate will support appropriate therapeutic...
Toribio RE.Critical illness challenges many endocrine homeostatic systems to overcome diseases, stress, and hostile conditions that threaten survival. Coordinated and consecutive responses by the autonomic nervous system, endocrine metabolic adaptations to mobilize and conserve energy and electrolytes, cardiovascular adjustments to maintain organ perfusion, and immunomodulation to overcome infections and inflammation are required. Because most admissions to equine intensive care units are related to horses with gastrointestinal disease and septic foals, most endocrine information during critical disease ...
Sloboda M, Jirků M, Lukešová D, Qablan M, Batsukh Z, Fiala I, Hořín P, Modrý D, Lukeš J.Equine piroplasmosis caused by Babesia caballi and Theileria equi is widespread in Asia. The presence of these haemozoans in Mongolia was previously confirmed in domestic as well as in reintroduced Przewalski horses in which they cause significant pathology. The data on occurrence of piroplasms from Bactrian camels in Asia is lacking. A total of 192 horses, 70 Bactrian camels, and additional 16 shepherd dogs from the Hentiy province were included in our study. No clinical signs typical for piroplasmid infection were observed during the field survey. Microscopic examination revealed the presenc...
McKenzie HC.Hyperlipidemia is the presence of elevated lipid concentrations in the blood and is associated with periods of negative energy balance and physiologic stress. In increased concentrations, circulating lipids typically occur in the triglyceride form, which may interfere with numerous normal physiologic functions, particularly by reducing insulin sensitivity. Although the hyperlipidemia risk is greatest in ponies, miniature horses, and donkeys, all equids are at risk if they are in a situation involving negative energy balance. The sedentary lifestyle of many modern horses and the frequent feedin...
McFarlane D.Equine pituitary pars intermedia dysfunction (PPID), also known as equine Cushing's syndrome, is a widely recognized disease of aged horses. Over the past two decades, the aged horse population has expanded significantly and in addition, client awareness of PPID has increased. As a result, there has been an increase in both diagnostic testing and treatment of the disease. This review focuses on the pathophysiology and clinical syndrome, as well as advances in diagnostic testing and treatment of PPID, with an emphasis on those findings that are new since the excellent comprehensive review by Sc...
Bolt DM, Burba DJ, Hubert JD, Pettifer GR, Hosgood GL.Extracorporeal shock wave therapy is becoming increasingly used in equine practice to treat musculoskeletal disorders. Although the exact effects of extracorporeal shock waves on tissues still need to be elucidated, transient cutaneous analgesia has been observed within treated areas in humans and horses. The purpose of this study was to determine the onset, magnitude, and duration of cutaneous analgesia after non-focused extracorporeal shock wave (ESW) application by comparing the limb withdrawal reflex latency (LWRL) in treated and untreated areas on the metacarpus of horses, using a focused...
Varner DD, Blanchard TL, Love CL, Garcia MC, Kenney RM.Two experiments were conducted to examine the effects of cooling rate and storage temperature on motility parameters of stallion spermatozoa. In Experiment 1, specific cooling rates to be used in Experiment 2 were established. In Experiment 2, three ejaculates from each of two stallions were diluted to 25 x 10(6) sperm/ml with 37 degrees C nonfat dry skim milk-glucose-penicillin-streptomycin seminal extender, then assigned to one of five treatments: 1) storage at 37 degrees C, 2) storage at 25 degrees C, 3) slow cooling rate to and storage at 4 degrees C, 4) moderate cooling rate to and storag...
Sanders RE, Kearney CM, Buckley CT, Jenner F, Brama PA.To evaluate knot security for 3 knot types created in 3 commonly used 5 metric suture materials incubated in physiological and pathological fluids. Methods: In vitro mechanical study. Methods: Knotted suture loops (n = 5/group). Methods: Loops of 3 different suture materials (glycolide/lactide copolymer; polyglactin 910; polydioxanone) were created around a 20 mm rod using 3 knot types (square [SQ], surgeon's [SK], and triple knot [TK]) and were tested to failure in distraction (6 mm/min) after tying (day 0) and after being incubated for 14 and 28 days in phosphate buffered saline (PBS...
Torbert BJ, Kramer BS, Klei TR.A controlled test was used in ponies to compare the antiparasitic efficacy of ivermectin (22,23-dihydro-avermectin B1) in an injectable micelle solution administered IM with the efficacy of the same drug in an oral paste formulation. Parasite infections were naturally acquired in southern Louisiana. The drug was tested in both formulations at a dosage level of 0.2 mg/kg of body weight. Ivermectin in both formulations tested had an efficacy greater than 98% against Gasterophilus intestinalis and G nasalis larvae. Trichostrongylus axei, Habronema spp, Strongylus vulgaris, S. edentatus, and speci...
Doube M, Firth EC, Boyde A.Combined backscattered electron scanning electron microscopy (BSE SEM) and confocal scanning laser microscopy (CSLM) have been used to put tissue mineralization data into the context of soft tissue histology and fluorescent label information. Mineralization density (Dm) and linear accretion rate (LAR) are quantifiable parameters associated with mineralizing fronts within calcified tissues. Quantitative BSE (qBSE) may be used to determine Dm, while CSLM may be used to detect label fluorescence from which LAR is calculated. Eighteen-month old Thoroughbred horses received single calcein injection...
Starik E, Ginter A, Coppe P.A monoclonal antibody (mAb) directed against the equine arteritis virus (EAV) nucleocapsid (N) protein was used for indirect enzyme-linked immunosorbent assays (ELISAs) using viral antigen from different sources. The same mAb was labelled with fluorescein isothiocyanate for direct immunofluorescence tests (DIFTs). The N-specific mAb appeared to be suitable for the detection in both ELISA and DIFT of different EAV strains and field isolates from semen and tissue samples after passage in lines of RK-13, Vero and fetal equine kidney cells. The ELISA described is an easy and fast method which can ...
Parmentier JIM, Bosch S, van der Zwaag BJ, Weishaupt MA, Gmel AI, Havinga PJM, van Weeren PR, Braganca FMS.Vertical ground reaction force (GRFz) measurements are the best tool for assessing horses' weight-bearing lameness. However, collection of these data is often impractical for clinical use. This study evaluates GRFz predicted using data from body-mounted IMUs and long short-term memory recurrent neural networks (LSTM-RNN). Twenty-four clinically sound horses, equipped with IMUs on the upper-body (UB) and each limb, walked and trotted on a GRFz measuring treadmill (TiF). Both systems were time-synchronised. Data from randomly selected 16, 4, and 4 horses formed training, validation, and test dat...
Fales-Williams A, Sponseller B, Flaherty H.A 6-year-old, gelded, Paint horse displayed clinical signs of muscle wasting and limb stiffness for a 6-month period. The horse's clinical signs abated with corticosteroid therapy, but returned upon cessation of treatment. Upon necropsy, severe lesions of aortic thickening and aortic valve rigidity were observed. Histologically, the tunica media of the aorta, coronary arteries, and pulmonary arteries were expanded by foci of elastin fiber calcification and extracellular matrix with lacunae formation. The vascular lesions are comparative to what has been described as medial arterial calcificati...
Allen D, Clark ES, Moore JN, Prasse KW.A carbohydrate overload model was used in 8 horses to evaluate Starling forces and hemodynamics of the digit during the prodromal stage of acute laminitis. A pump-perfused extracorporeal digital preparation was used to evaluate blood flow, arterial pressure, venous pressure, capillary pressure, isogravimetric capillary filtration coefficient, osmotic reflection coefficient, and vascular compliance. From these data, pre- and postcapillary resistances and pre- to postcapillary resistance ratios were determined. Vascular and tissue oncotic pressures were estimated from plasma and lymph protein co...
DiMaio Knych HK, DeStefano Shields C, Buckpitt AR, Stanley SD.Substantial gaps exist in our knowledge of the metabolic clearance of therapeutic agents in horses. Accordingly, a cytochrome P450 monooxygenase in the 2C family was cloned from an equine liver, sequenced and expressed in a baculovirus expression system. Catalytic activities of the recombinant protein were measured with a number of substrates. The protein, assigned CYP2C92, displayed optimal catalytic activity with diclofenac using molar ratios of CYP2C92 to NADPH CYP450 reductase of 1:18. Addition of cytochrome b(5) to diclofenac incubations had no significant effect on metabolic turnover. CY...
Mimoun L, Steinman A, Kliachko Y, Tirosh-Levy S, Schvartz G, Blinder E, Baneth G, Mazuz ML.Equine Neospora infection has been linked to neurological disorders and infertility in horses. This study looked into the risk factors for infection and the exposure to Neospora spp. in horses. The study was performed in two independent populations in Israel. The first consisted of apparently healthy horses, and the second consisted of mares examined during pregnancy and after parturition. Sera samples collected from horses and mares were tested for Neospora exposure by the indirect fluorescent antibody test (IFAT). The study revealed seroprevalence of 24% in apparently healthy horses and 66.4...
Luo Y, Uboh CE, Soma LR, Guan F, Rudy JA, Tsang DS.This method describes the simultaneous separation, identification, quantification and confirmation of betamethasone (BTM) and dexamethasone (DXM) in equine plasma by liquid chromatography (LC) integrated with multidimensional tandem mass spectrometry. Analytes were directly extracted from equine plasma by methyl tert-butyl ether (MTBE). The residues were reconstituted with sample solvent. LC separation of the analytes was performed on a Hypercarb column using acetonitrile/water/formic acid (95:5:0.5, v/v/v) as the mobile phase. Sample screening, quantification and confirmation were performed i...
Davies Morel MC, Gunnarsson V.Very limited information is available on the breeding performance of Icelandic stallions, let alone the effect that management practices may have had on such performance. As an extensively kept, largely genetically isolated breed of horse it provides a good model for the study of factors that affect reproductive performance without the additional complication of selective breeding, infectious infertility and breed effect. A survey was conducted using 27 Icelandic stallions covering 1590 mares within the normal Icelandic breeding system (May to September). During the season, stallions cover mar...
Easley JT, Freeman DE.The diagnosis and treatment of equine dental-related sinus disease is often challenging. Dental-related sinus disease is common and knowledge of these diseases is becoming increasingly important in veterinary medicine. Diagnostic capabilities are continually improving, leading to early diagnostic and therapeutic successes. With advanced imaging modalities, such as computed tomography and magnetic resonance imaging, understanding of the intimate anatomic relationship between teeth and the paranasal sinuses continues to progress. There are many therapeutic options available for the treatment of ...
Heinrich A, Riethmüller D, Gloger M, Schusser GF, Giese M, Ulbert S.Equine Arteritis Virus (EAV) belongs to the Arteriviridae and causes viral arteritis in horses. In an attempt to develop novel and save therapies against the infection it was tested whether EAV is susceptible to RNA interference (RNAi) in an equine in vitro system. Horse cells were transfected with chemically synthesized small interfering RNA oligonucleotides (siRNAs) and challenged with EAV. Application of these siRNAs led to a significant protection of the cells, and virus titers decreased drastically. siRNAs derived from DNA plasmids expressing small hairpin RNAs (shRNAs) were also effectiv...
Craigo JK, Ezzelarab C, Cook SJ, Chong L, Horohov D, Issel CJ, Montelaro RC.Lentiviral envelope (Env) antigenic variation and associated immune evasion present major obstacles to vaccine development. The concept that Env is a critical determinant for vaccine efficacy is well accepted, however defined correlates of protection associated with Env variation have yet to be determined. We reported an attenuated equine infectious anemia virus (EIAV) vaccine study that directly examined the effect of lentiviral Env sequence variation on vaccine efficacy. The study identified a significant, inverse, linear correlation between vaccine efficacy and increasing divergence of the ...
Lees VW, Gale SP.Sera from horses in Alberta, submitted to Agriculture and Agri-Food Canada for routine testing for equine infectious anemia from January 1987 to June 1989, were tested for antibody against 13 serovars of pathogenic Leptospira spp., using the microscopic agglutination test. The purpose of the study was to investigate the prevalence of serum titers to those serovars in horses in Alberta, and to analyze the associated risk factors. Descriptive statistics were compiled and logistic regressions were computed. Titers to L. interrogans serovars icterohaemorrhagiae, bratislava, copenhageni, and autumn...
Prieto D, Arcos LR, Martínez P, Benedito S, García-Sacristán A, Hernández M.The distribution of neuropeptide Y (NPY)-immunorective nerves and the receptors involved in the effects of NPY upon electrical field stimulation (EFS)- and noradrenaline (NA)-elicited contractions were investigated in horse penile small arteries. NPY-immunoreactive nerves were widely distributed in the erectile tissues with a particularly high density around penile intracavernous small arteries. In small arteries isolated from the proximal part of the corpora cavernosa, NPY (30 nM) produced a variable modest enhancement of the contractions elicited by both EFS and NA. At the same concentration...
Wysocka B, Kluciński W.The goal of the present study was to establish the occurrence of structural disorders in the larynx and pharynx during treadmill exercise tests in horses diagnosed with Equine Asthma (EA). Investigation was performed in 29 horses, patients of the Equine Clinic of the Warsaw University of Life Sciences in Poland, admitted with poor exercise performance. Upper and lower airway examinations were performed in all patients revealing both mild to moderate Equine Asthma (13 horses), and no lower airway abnormalities (16 animals). In the group of horses with EA, 11 did not have structural disorders of...
Kirschvink N, Fiévez L, Dogné S, Bureau F, Art T, Lekeux P.Solute analysis in bronchoalveolar lavage fluid involves the use of dilutional markers to correct for variable recovery of pulmonary epithelial lining fluid (PELF). Urea is the best characterised endogenous marker, whereas inulin appears to meet the requirements of an exogenous marker. In horses, the use of inulin has never been investigated and the impact of lower airway diseases such as heaves, on PELF recovery is unknown. In this study, five healthy and five heaves-affected horses underwent airway endoscopy and bronchoalveolar lavage. PELF recovery from bronchoalveolar lavage was calculated...
Blunden AS, Mackintosh ME.A series of 31 thoroughbreds and 18 non-thoroughbreds was examined post mortem to assess what bacteria might be present in the lower respiratory tract, and to assess their significance by correlating the bacteriological findings with histological changes in the lung. The distal trachea and seven representative lung sites were swabbed in each case. Sixty-six per cent of the sites were sterile with remaining sites producing scanty growths of mainly coagulase negative Staphylococcus spp., E. coli, Bacillus spp. and Pseudomonas spp. Anaerobes, mainly Clostridium perfringens, Bacteroides fragilis a...
Sano Y, Matsuda K, Osaki K, Miyasho T, Tsuda T, Taniyama H.A male Thoroughbred fetus was aborted on day 251 of pregnancy. Gross and histological examinations detected systemic granulomatous lesions in many superficial and visceral lymph nodes and organs including the liver, tonsils, lungs, thymus, spleen, right thyroid gland and gastrointestinal tract, and suppurative placentitis, pyogranulomatous amnionitis and intralesional acid-fast bacilli were also detected. An examination of the DNA base sequence of the β subunit of RNA polymerase demonstrated that Mycobacterium avium strain 104 had infected several organs. To the best of our knowledge, this is...
Turner TA, Fessler JF, Lamp M, Pearce JA, Geddes LA.The distal forelimbs of 10 clinically normal horses with hair clipped on 1 limb were thermographically scanned before and after exercise. The thermal patterns, temperature distribution, and temperature changes after exercise were determined and compared with those of 8 horses with podotrochlosis. Clipping the hair did not cause changes in the thermal patterns, but the clipped limbs were warmer than the unclipped limbs. The temperature of the limbs of horses with podotrochlosis did not increase as much after exercise as did the limbs of normal horses. The failure of skin temperature increase co...
Linardi RL, Stokes AM, Andrews FM.Methadone is an effective analgesic opioid that may have a place for the treatment of pain in horses. However, its absorption seems to be impaired by the presence of a transmembrane protein, P-glycoprotein, present in different tissues including the small intestine in other species. This study aims to determine the effect of the P-glycoprotein on methadone flux in the equine intestinal mucosa, as an indicator of in vivo drug absorption. Jejunum tissues from five horses were placed into the Ussing chambers and exposed to methadone solution in the presence or absence of Rhodamine 123 or verapami...
Nostell K, Lindåse S, Edberg H, Bröjer J.There is little evidence that horses with equine metabolic syndrome (EMS) have higher resting blood pressures than horses with normal insulin sensitivity. However, there are indications that EMS horses have an altered dynamic response to the cardiovascular effects of insulin. Objective: To examine heart rate and the systemic blood pressure response in EMS and control horses during insulin infusion. Methods: Cross-sectional study. Methods: Horses were examined with an oral sugar test (OST) and a euglycaemic hyperinsulinaemic clamp (EHC). Based on the results from the OST, the horses were classi...
Gygax D, Lischer C, Auer JA.To compare the precision of computer-assisted surgery with a conventional technique (CV) using a special guiding device for screw insertion into the distal sesamoid bone in horses. Methods: In vitro experimental study. Methods: Cadaveric forelimb specimens. Methods: Insertion of a 3.5 mm cortex screw in lag fashion along the longitudinal axis of intact (non-fractured) distal sesamoid bones was evaluated in 2 groups (8 limbs each): CV and computer-assisted surgery (CAS). For CV, the screw was inserted using a special guiding device and fluoroscopy, whereas for CAS, the screw was inserted using ...
Sluyter FJ.The accelerated speed of animal transport and the existence of complex and intricate movement systems have created an equine population in motion. This ease in the international movement of horses has an impact on the risk of introduction or spread of disease, specifically in relation to competition horses. Facilitating trade in Equidae, whilst simultaneously safeguarding the health status of the receiving country is a major challenge. To date, the international regulatory bodies are prepared to consider movement of registered horses as a relatively 'low risk' occurrence and thereby apply the ...
Braucke AFGV, Frederiksen NL, Berg LC, Aarsvold S, Müller FC, Boesen MP, Lindegaard C.Joint pain and osteoarthritis (OA) are some of the most common causes of lameness in horses, and most of the available treatments focus on symptomatic relief without a disease-modifying effect. TRPV1 is a potential target for treating joint diseases, including OA, and the present study aims to investigate if the TRPV1 receptor is present in equine articular tissue and determine whether the number of receptors is upregulated in joint inflammation. Metacarpo/metatarsophalangeal (MCP/MTP) joints from 15 horses euthanised for reasons unrelated to this study were included. Based on synovial fluid a...
Morris DD, Moore JN, Ward S.A study, at a university in south eastern USA, aimed to determine whether age, sex, breed, management and history differed in colic cases. A detailed history was obtained for 229 horses between January 1987 and June 1988. Causes for colic determined by clinical examination, exploratory laparotomy and/or necropsy included: gastric rupture (GR, 6); ileal impaction (II, 17); small intestinal strangulating obstruction (SIO, 22); proximal enteritis (PE, 16); transient small intestinal distension (TSID, 18); large colon displacement (LCD, 52); large colon impaction (LCI, 34); colitis (8); small colo...
Stewart RH, Reed SM, Weisbrode SE.We compared the frequency and severity of osteochondrosis lesions in young Thoroughbred horses with cervical stenotic myelopathy (CSM) vs that in clinically normal Thoroughbreds of the same age. All lesions of the cervical vertebrae and appendicular skeleton were classified histologically as osteochondrosis or nonosteochondrosis and were measured for severity. Minimal sagittal diameter was significantly smaller in horses with CSM from C2 through C6; no difference was detected at C7. Severity of cervical vertebral osteochondrosis was greater in the horses with CSM, however frequency was not dif...