Disease diagnosis in horses involves the identification and characterization of illnesses through various diagnostic methods and tools. This process is essential for effective veterinary care and management of equine health. Techniques used in diagnosing diseases in horses include clinical examinations, laboratory tests, imaging modalities such as ultrasonography and radiography, and molecular diagnostics. Blood tests are frequently utilized to assess parameters such as complete blood count and biochemical profiles, which can indicate underlying health issues. Additionally, advancements in genetic testing and biomarker identification have enhanced the ability to detect specific diseases early. This page aggregates peer-reviewed research studies and scholarly articles that explore diagnostic methodologies, their applications, and their impact on equine health management.
van der Graaf L, Leigh W, Szmatoła T, Roberts K, Ryan S, Brown B, Van Buren S, Finno CJ, Petersen JL.Anhidrosis is defined as a decreased or absent ability to sweat in response to heat and exercise. In horses, this condition can increase the risk of life-threatening hyperthermia. A prior study has suggested that equine anhidrosis is associated with a missense variant (rs68643109) in the Potassium Voltage-Gated Channel Subfamily E Regulatory Subunit 4 (KCNE4) gene. This project aimed to validate this association in a population of well-phenotyped horses and to determine the allele frequency of this variant in publicly available whole-genome sequence data. Fifty horses within the University of ...
Stricklin OE, McKenzie EC, Sriboonyapirat P, Russell DS, White CN.To determine whether Miniature Horse mares are predisposed to hemoperitoneum from nonneoplastic ovarian hemorrhage and report the clinical characteristics of this disorder. Methods: 51 equines with hemoperitoneum, including 22 nonminiature mares and 9 Miniature Horse mares, identified by searching medical records of a tertiary large animal hospital for confirmed hemoperitoneum cases between 2012 and 2023. Methods: Signs of hemoperitoneum in miniature mares included lethargy, inappetence, colic, tachycardia, and moderate to severe anemia (PCV ranging from 11% to 19%). Five miniature mares did n...
Poizat E, Gérard M, Macaire C, De Azevedo E, Denoix JM, Coudry V, Jacquet S, Bertoni L, Tallaj A, Audigié F, Hatrisse C, Hébert C, Martin P....Lameness detection in horses is a critical challenge in equine veterinary practice, particularly when symptoms are mild. This study aimed to develop a predictive system using a support vector machine (SVM) to identify the affected limb in horses trotting in a straight line. The system analyzed data from inertial measurement units (IMUs) placed on the horse's head, withers, and pelvis, using variables such as vertical displacement and retraction angles. A total of 287 horses were included, with 256 showing single-limb lameness and 31 classified as sound. The model achieved an overall accuracy o...
Wright CA, Lawton K, Barnum S, Craig BW, Farwell BR, Blea J, McCook C, Pusterla N.This study aimed to determine if exercise increases the frequency of selected respiratory viruses/bacteria shedding in non-clinical horses using nose wipes. Nose wipes were taken pre- and post- exercise from 133 healthy horses of various ages and disciplines. Wipes were assayed for the presence of selected common (equine herpesvirus-1 (EHV), EHV-4, S. equi spp equi) and commensal (EHV-2, EHV-5, S. equi spp zooepidemicus) respiratory pathogens. The frequency of detection increased significantly (p < 0.05) in the post-exercise wipes for EHV-1, EHV-2, EHV-5, and S. zooepidemicus. EHV-4 and S. equ...
Finno CJ, Rogers SL, Donnelly CG, Affolter VK, Woolard K, Miller AD, Bellone RR, Petersen JL.Equine spinal neurodegenerative conditions are frequently encountered in sport and racing horses and may be career-ending diagnoses. To further define the spatial transcriptomic landscape of equine dorsal root ganglia (DRG) in healthy adult horses, we investigated gene expression differences in distinct DRG regions using the GeoMx Digital Spatial Profiling from NanoString. Four human cell markers demonstrated high fidelity for equine cells; microtubule-associated protein 2 (MAP2), myelin basic protein (MBP), allograft inflammatory 104 factor 1/ionized calcium-binding adaptor molecule 1 (IBA1/A...
Facile V, Magliocca M, Dini FM, Imposimato I, Mariella J, Freccero F, Urbani L, Rinnovati R, Sel E, Gallina L, Castagnetti C, Galuppi R, Battilani M....Equine piroplasmosis is a tick-borne disease caused by and species. Despite its presence in Europe, no laboratory testing is required for animal movement, even though some countries remain free of this disease. Differentiating between species and genotypes is crucial to determine the most effective treatment, as dosage, active compounds, and duration vary. However, diagnosis is often challenging due to genetic variability and the limited sensitivity of molecular methods. The aims of this study were to compare the performances of different molecular diagnostic tests to identify the most effec...
Tretow M, Hain AM, Bienert-Zeit A.Equine odontoclastic tooth resorption and hypercementosis (EOTRH) is a widespread dental disease with an unknown aetiology, mainly affecting the incisors and canine teeth of senior horses. Being clinically asymptomatic in early stages but progressively destructive and painful in many cases highlights the need for improvements in early diagnosis of EOTRH. This study describes how clinical and radiological findings correlate with distinguishing EOTRH-specific symptoms from non-specific findings. Clinical and radiographic examinations of the rostral oral cavity were performed in 154 Icelandic hor...
Valberg SJ.Although horses most commonly develop exertional rhabdomyolysis, there are numerous causes for nonexertional rhabdomyolysis (nonER) that pose a serious health threat to horses. Their etiologies can be broadly categorized as toxic, genetic, inflammatory/infectious, nutritional, and traumatic and a variety of diagnostic tests are available to discern among them. This study discusses causes of nonER as well as diagnostics and treatments that are specific to each etiology. General treatment of acute rhabdomyolysis is covered in detail in the study in this issue on sporadic and recurrent exertional...
Kozak S, Merda D, Chesnais V, Breuil MF, Harrison M, Zdovc I, Golob M, Petry S, Duquesne F.Taylorella equigenitalis is the causative agent of contagious equine metritis, an internationally regulated sexually-transmitted infection in horses, which is of great concern as it usually results in temporary infertility. Taylorella asinigenitalis, the second member of the genus, is mainly found in donkeys and is considered non-pathogenic, although a first natural outbreak was reported in 2019 in the United Arab Emirates. Multilocus sequence typing (MLST) is currently used to study the epidemiology of Taylorella spp. but, while highly transposable and reproducible, it only focuses on < 0.5...
Helbig H, Berghaus LJ, Venner M, Berghaus R, Hart KA.Adequate vitamin availability is vital for cellular and immune function and for normal growth. Available data on age-related changes in serum concentrations of vitamins in foals are limited. In addition, associations between circulating vitamin concentrations and the development of bronchopneumonia in foals are not described. Objective: (1) To quantify circulating concentrations of vitamins C, D and E from birth to weaning in foals; (2) to determine associations between vitamin concentrations and the development of bronchopneumonia during this period. Methods: Prospective cohort study. Methods...
McKenzie E.The equine muscle system is complex and prone to a large range of hereditary and acquired diseases that often have overlapping clinical signs with orthopedic, neurologic, and other disorders. Obtaining a clinical history that fully outlines the client concerns and any known information about the disorder and following with a comprehensive physical examination and screening clinical pathology tests are fundamental to achieve definitive diagnosis. A methodical and comprehensive approach aids accurate diagnosis and development of an optimal treatment and management plan. This article describes th...
Yu YT, Olarte Castillo X, Reboul G, Zehr J, Sun Y, Anderson R, Wang M, Sun Q, Tallmadge R, Sams K, Brown J, Marra N, Stanhope B, Grenier J.... is a parvovirus that was identified in the blood of four horses in the United States. Here, we report one genome from a horse in New York State. This genome may represent a new species within the genus .
Finno CJ.In the field of equine muscle disorders, many conditions have a genetic basis. Therefore, genetic testing is an important part of the diagnostic evaluation. Validated genetic tests are currently available for 5 equine muscle disorders: hyperkalemic periodic paralysis, malignant hyperthermia, glycogen branching enzyme disease, type 1 polysaccharide storage myopathy, and myosin heavy chain myopathy. These diseases should be tested for in the appropriate breeds with clinical signs of disease or as part of breeding management. Genetic testing in veterinary medicine is not regulated, and therefore,...
Jurisic L, Auerswald H, Marcacci M, Di Giallonardo F, Coetzee LM, Curini V, Averaimo D, Ortiz-Baez AS, Cammà C, Di Teodoro G, Richt JA, Holmes EC....Members of the RNA virus order infect hosts ranging from marine invertebrates to terrestrial mammals. As such, understanding the determinants of host range in this group of viruses, as well as their patterns of emergence and disease potential, is of clear importance. The are a recently documented family within the . To date, mesoniviruses have only been associated with the infection of arthropod species, particularly mosquitoes, and hence are regarded as insect-specific viruses (ISVs). Herein, we report the first detection of a mesonivirus-Alphamesonivirus-1 -in mammals. Specifically, we uti...
Shi Y, Maga EA, Mienaltowski MJ.Diarrhea is a common disease that could threaten the welfare of newborn foals. While there are several forms of foal diarrhea, the etiologies can be considered known pathogenic or non-pathogenic in nature. Moreover, there are likely differences in the composition of microbial populations in the gastrointestinal tracts of foals depending upon the etiology of diarrhea. Our study aims to examine the microbial population in the feces of foals with both pathogenic and non-pathogenic diarrheas to discern differences in their microbial compositions. Results: Foal diarrhea samples tested positive or n...
Hinrichs K, Gleason K, Dobbie T, Felix MR.Transvaginal ultrasound-guided follicle aspiration (TVA) is being performed frequently in equine practice, to recover oocytes for in vitro embryo production via intracytoplasmic sperm injection. While complications from TVA are rare, one of the most prevalent major complications is formation of an ovarian abscess, which can result in the necessity for euthanasia. The acute-phase serum proteins, fibrinogen and serum amyloid A (SAA), are markers of inflammation that might be of use in diagnosis of ovarian abscess. However, no information is available on the effect of standard TVA on these acute ...
Nugent Z, Jensen A, Owen N, Peffers AJ, Moothanchery M, Peffers MJ.Equine odontoclastic tooth resorption and hypercementosis (EOTRH) is a painful disorder primarily affecting the incisor teeth of horses over 15 years of age. Clinical signs of the disease include prehension problems, halitosis and in severe cases weight loss. The disease predominately affects the reserve crown and presents as a loss of dental tissue and excessive build-up of cementum. Objective: To determine the radiographic scores of horses with EOTRH and age-matched controls and to increase understanding of EOTRH using microCT to compare teeth from horses with EOTRH and age-matched control...
Nemoto M, Kawanishi N, Kambayashi Y, Bannai H, Yamanaka T, Tsujimura K.Equine influenza virus (EIV) can be transmitted by inhalation of aerosolized droplets, direct contact, and contaminated fomites. However, to our knowledge, there are no reports of the recovery of EIV from the air surrounding infected horses. Here, we evaluated whether EIV can be recovered from the air in the stalls of experimentally infected horses by using an air sampler. Furthermore, we examined whether rapid molecular test kits with reaction times of less than 30 min can detect EIV from air samples for potential field application. Two horses kept in individual stalls were experimentally i...
Jensen A, Clarke EJ, Nugent Z, Paice E, Gringel I, Yamamoto K, Rocchigiani G, Peffers AJ, Cooper L, Peffers MJ.Equine dental diseases significantly impact a horse's overall health, performance and quality of life. They can result in secondary infections and digestive disturbances, potentially leading to colic. A recently described disease affecting the incisors of horses is equine odontoclastic tooth resorption and hypercementosis (EOTRH). Understanding EOTRH is crucial for early diagnosis, effective management and prevention of its severe consequences. Objective: To determine proteomic differences in incisor cementum in horses with and without clinical EOTRH. Methods: Comparative and observational cli...
Albert E, Biksi I, Laczkó L, Miló L, Cseri K, Bőkényné Tóth R, Papp D, Halmay D, Bódai E, Bakos Z.Here we report the isolation of Streptococcus hillyeri from a thoracic sample from a horse. A 17-y-old Hungarian Sport Horse mare was referred to the equine clinic of the University of Veterinary Medicine Budapest, Hungary, with suspected pleuritis. Upon arrival, the horse was febrile and had tachycardia, severe inspiratory dyspnea, and tachypnea. Thoracic ultrasonography revealed severe bilateral pleural effusion, and a large area of lung consolidation. After sampling of both hemithoraces, 66 L of turbid exudate were drained. Based on these findings, a tentative diagnosis of septic pleuritis ...
Carvalho Serena G, Marchezan Piva M, Viezzer Bianchi M, Fernandes da Fonseca HC, Chitolina Pupin R, Martins Basso R, Secorun Borges A....In horses, systemic calcinosis is a rare syndrome characterised by muscle lesion associated with the mineralisation of large muscle groups or other organs, in the absence of an alternative cause for the calcification, such as toxic, enzootic or metabolic. Molecular and histopathological aspects of the disease are still poorly elucidated. Objective: To describe the epidemiological, pathological and molecular aspects of systemic calcinosis in a convenience sample of six horses submitted to necropsy in the Southern and Midwestern regions of Brazil. Methods: Retrospective exploratory study. Method...
Torcivia C, McDonnell SM.Gastric ulcer disease and other potentially painful gastric conditions are among the most common afflictions adversely affecting the welfare of domestic equids. A large percentage of affected animals may not display the classic signs of gastric disease, such as unexplained weight loss, poor hair coat, and inappetence until the disease becomes severe. As a clinical service within our equine referral hospital, we routinely evaluate 24-h video recorded samples of horses to assist clinicians in identifying subtle discomfort and potential sources or to scan for infrequent neurologic or cardiac-rela...
Daradics Z, Bungărdean D, Lupșan AF, Popescu M, Bulmez O, Ciulu-Angelescu V, Chelaru VF, Morar I, Mircean M, Cătoi C, Tripon MA, Crecan CM.Ethylene glycol toxicosis is a common occurrence in dogs and cats but has been reported in other species as well. Up to date, only one case of ethylene glycol toxicosis has been described in horses, and specific guidelines for treating ethylene glycol intoxication in this species are not available. Here we describe the case of 39 sport horses that ingested water contaminated with ethylene glycol. The main clinical sign was apathy, but more severely affected individuals also developed abdominal pain and laminitis. Treatment was initiated around 24 h after the exposure, using ethanol as an antid...
Fernandes T, Robin M, Freeman KP.Biological variation in laboratory results refers to physiological fluctuations that occur around a homeostatic setpoint (HSP) for various laboratory measurands. Assessment of biological variation includes determining individual variation (CV), group variation (CV), and analytical variation (CV). Reference change value (RCV) is an objective tool for an evidence-based approach to interpret data by assessing the significance of consecutive results in an individual for the diagnosis, prognosis, and monitoring of disease. The individualised reference intervals (iRI) are derived from the determinat...
Castro D, Clark-Price S.Pre-existing muscle disorders in horses can often be subtle and may only become evident during or after anesthesia. Advancements in veterinary medicine, along with increased knowledge and research in this field, help minimize anesthesia-related problems. Adequate preanesthesia assessment, early disease diagnosis, and proper management are crucial in minimizing risks to the neuromuscular system during general anesthesia.
Ekinci G, Deniz O, Tüfekci E, Timur MC, Onmaz AC, Günes V, Citil M, Keles I, Hoven RVD.Rhodococcus equi (R. equi) is a primary cause of pyogranulomatous pneumonia of foals between three weeks and five months of age. Early diagnosis of rhodococcal pneumonia has always been considered a preferable approach as it can lead to more successful treatment and better outcomes. Horse stud farms where the disease is common, neonatal foals are subjected to tests such as complete blood count and fibrinogen analysis at certain intervals. However, new biomarkers are needed in addition to blood count and fibrinogen measurement in this field for early diagnosis of diseases. Based on this need, i...
Vinijkumthorn R, Kingkaw A, Yanyongsirikarn P, Phaonakrop N, Roytrakul S, Vongsangnak W, Tesena P.Equine melanocytic neoplasm (EMN) represents a form of skin tumor observed predominantly in grey horses aged over 15 years. Despite its prevalence, current therapeutic and preventive strategies for EMN have been subject to limited investigation. This study endeavors to shed light on potential phosphoproteins present in equine serum and fecal samples, potentially linked to EMN, with a specific focus on functional interactions in EMN pathogenesis. We examined 50 samples (25 serum, 25 feces), divided into three groups based on EMN severity: normal (n = 16), mild (n = 18), and severe EMN (...
Baghdadi HBA, Abdelsalam M, Attia MM.Strongylus vulgaris, a devastating parasitic nematode in equids, causes life-threatening verminous aneurysms that are challenging to diagnose early. This study pioneered integrating nanotechnology into an indirect enzyme-linked immunosorbent assay (i-ELISA) system to enhance the sensitivity and specificity for detecting S. vulgaris larval antigens in equine serum samples, with PCR confirmation of the species. A conventional i-ELISA and an innovative nano-based ELISA were developed using excretory-secretory antigens from adult S. vulgaris worms. The nano-ELISA incorporated gold nanoparticles (1...
Benitez-Ibalo AP, Debárbora VN, Mangold AJ, Nava S, Sebastian PS.After the previous description and characterization of Theileria equi sensu stricto (Genotype A) in Argentina, the aim of the present study was to investigate the possible heterogeneity of 18 S rDNA genotypes circulating in this country. Therefore, blood samples from 18 horses from two different neighborhoods of Corrientes City, Corrientes Province, were analyzed for infection with Theileria species. Theileria DNA was detected in five samples (27.8%). Four nearly complete 18 S rDNA gene sequences were obtained and phylogenetic analyses were carried out. The maximum likelihood tree constructe...
Valderrama-Martinez C, Packham A, Zheng S, Smith W, Plancarte M, Aleman M.Evaluating antibody titers for Sarcocystis neurona for the diagnosis of equine protozoal myeloencephalitis from serum samples is a common practice. However, ensuring timely and proper refrigeration is not always possible. Objective: To evaluate immunofluorescent antibody (IFA) titers for S. neurona from serum samples stored at room temperature and 4°C. Methods: Twenty-two serum samples. Methods: Prospective longitudinal study. Two serum aliquots of 1 mL each were stored at room temperature (20-23.3°C) and 4°C. The unrefrigerated aliquot was immediately tested for IFA titers. Both aliquots...
van Duijkeren E, Moleman M, Sloet van Oldruitenborgh-Oosterbaan MM, Multem J, Troelstra A, Fluit AC, van Wamel WJ, Houwers DJ, de Neeling AJ....At the Veterinary Microbiological Diagnostic Center, the Netherlands, the percentage of methicillin-resistant Staphylococcus aureus (MRSA) isolates found in equine clinical samples increased from 0% in 2002 to 37% in 2008. MRSA of spa-type t064, belonging to MLST ST8 and spa-types t011 and t2123, both belonging to the livestock-associated MLST ST398, predominated. During an outbreak of post-surgical MRSA infections in horses at a veterinary teaching hospital in 2006/2007, MRSA isolates of spa-type t2123 were cultured from 7 horses and 4/61 personnel which indicated zoonotic transmission. After...
Eddy AL, Van Hoogmoed LM, Snyder JR.Equine thermography has increased in popularity recently because of improvements in thermal cameras and advances in image-processing software. The basic principle of thermography involves the transformation of surface heat from an object into a pictorial representation. The colour gradients generated reflect differences in the emitted heat. Variations from normal can be used to detect lameness or regions of inflammation in horses. Units can be so sensitive that flexor tendon injuries can be detected before the horse develops clinical lameness. Thermography has been used to evaluate several dif...
Giguère S, Viel L, Lee E, MacKay RJ, Hernandez J, Franchini M.Work in humans and laboratory animals has identified a central role for cytokines and chemokines in development and persistence of lower airway inflammation. The objectives of this study were to determine interleukin (IL)-1 beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha induction in bronchoalveolar lavage (BAL) of control horses and horses with heaves both during remission and exacerbation of the disease, and to determine the effect of therapy with inhaled fluticasone propionate on the cytokine profile of horses with heaves. IL-1 beta an...
Giguère S, Cohen ND, Chaffin MK, Hines SA, Hondalus MK, Prescott JF, Slovis NM.Pneumonia is a major cause of disease and death in foals. Rhodococcus equi, a gram-positive facultative intracellular pathogen, is a common cause of pneumonia in foals. This article reviews the clinical manifestations of infection caused by R. equi in foals and summarizes current knowledge regarding mechanisms of virulence of, and immunity to, R. equi. A complementary consensus statement providing recommendations for the diagnosis, treatment, control, and prevention of infections caused by R. equi in foals can be found in the same issue of the Journal.
Hilbe M, Herrsche R, Kolodziejek J, Nowotny N, Zlinszky K, Ehrensperger F.Borna disease virus (BDV) is the causative agent of severe T-cell-mediated meningoencephalitis in horses, sheep, and other animal species in central Europe. Here we report the first unequivocal detection of a BDV reservoir species, the bicolored white-toothed shrew, Crocidura leucodon, in an area in Switzerland with endemic Borna disease.
Carter RA, Treiber KH, Geor RJ, Douglass L, Harris PA.The ability to predict ponies at increased risk of laminitic episodes, when exposed to nutrient dense pasture, would facilitate management to avoid disease. Objective: To identify variables and clinically useful cut-off values with reproducible diagnostic accuracy for the prediction of ponies that subsequently developed laminitis when exposed to nutrient dense pasture. Methods: A cohort of predominantly Welsh and Dartmoor ponies from a closed herd was evaluated in March 2006 (n = 74) and March 2007 (n = 57). Ponies were categorised as never laminitic or previously laminitic according to report...
Metallinos DL, Bowling AT, Rine J.Lethal White Foal Syndrome is a disease associated with horse breeds that register white coat spotting patterns. Breedings between particular spotted horses, generally described as frame overo, produce some foals that, in contrast to their parents, are all white or nearly all white and die shortly after birth of severe intestinal blockage. These foals have aganglionosis characterized by a lack of submucosal and myenteric ganglia from the distal small intestine to the large intestine, similar to human Hirschsprung Disease. Some sporadic and familial cases of Hirschsprung Disease are due to muta...
Pauvolid-Corrêa A, Campos Z, Juliano R, Velez J, Nogueira RM, Komar N.A recent study reported neutralizing antibodies to West Nile virus (WNV) in horses from four ranches of southern Pantanal. To extend that study, a serosurvey for WNV and 11 Brazilian flaviviruses was conducted with 760 equines, 238 sheep and 61 caimans from 17 local cattle ranches. Among the tested equines, 32 were collected from a ranch where a neurologic disorder outbreak had been recently reported. The sera were initially screened by using a blocking ELISA and then titrated by 90% plaque-reduction neutralization test (PRNT90) for 12 flaviviruses. Employing the criterion of 4-fold greater ti...
De Cock AW, Mendoza L, Padhye AA, Ajello L, Kaufman L.Pythium insidiosum sp. nov., the etiologic agent of pythiosis, a cosmopolitan disease of horses, cattle, and dogs, is described and illustrated.
Thorpe CT, Udeze CP, Birch HL, Clegg PD, Screen HR.Age-related tendinopathy is common in both humans and horses; the initiation and progression of which is similar between species. The majority of tendon injuries occur to high-strain energy storing tendons, such as the human Achilles tendon and equine superficial digital flexor (SDFT). By contrast, the low-strain positional human anterior tibialis tendon and equine common digital extensor (CDET) are rarely injured. It has previously been established that greater extension occurs at the fascicular interface in the SDFT than in the CDET; this may facilitate the large strains experienced during l...
Wagner B, Freer H.The detection and quantification of equine cytokines has been hampered by the lack of antibodies for many years. With the development of antibody pairs for equine cytokines during the past years, the quantification of these essential regulators of the immune response became possible. After being successfully tested by enzyme-linked immunosorbent assays (ELISA), three of these anti-cytokine reagents were used here to establish the first cytokine multiplex assay for equine IL-4, IL-10 and IFN-alpha. A fluorescent bead-based system was used as matrix for this assay that allows the simultaneous de...
Marsh GA, Wang LF.Henipavirus, including Hendra and Nipah viruses, is a group of emerging bat-borne paramyxoviruses which were responsible for severe disease outbreaks in humans, horses and pigs. The mortality rate of human infection varies between 50 and 100%, making them one of the most deadly viruses known to infect humans. Its use of highly conserved cell surface molecules (ephrin) as entry receptors and its highly effective replication and fusion strategies are believed to be important characteristics responsible for its high pathogenicity. Henipavirus also encodes multiple accessory proteins which play a ...
Kappmeyer LS, Thiagarajan M, Herndon DR, Ramsay JD, Caler E, Djikeng A, Gillespie JJ, Lau AO, Roalson EH, Silva JC, Silva MG, Suarez CE, Ueti MW....Transmission of arthropod-borne apicomplexan parasites that cause disease and result in death or persistent infection represents a major challenge to global human and animal health. First described in 1901 as Piroplasma equi, this re-emergent apicomplexan parasite was renamed Babesia equi and subsequently Theileria equi, reflecting an uncertain taxonomy. Understanding mechanisms by which apicomplexan parasites evade immune or chemotherapeutic elimination is required for development of effective vaccines or chemotherapeutics. The continued risk of transmission of T. equi from clinically silent,...
Labruna MB, Kasai N, Ferreira F, Faccini JL, Gennari SM.Natural tick infestations were assessed every 14 days on horses over a 2-year period. Amblyomma cajennense adult ticks were counted individually, without detachment from the horses. Larvae and nymphs of A. cajennense were collected using a rubber scraper that scratched engorged immature ticks from the host. Adult females of Anocentor nitens larger than 4mm length were counted on the horses. Blood samples were also obtained from the horses every 14 days and macroclimatic data were obtained for the study period. Infestations of A. cajennense demonstrated distinct peaks of activity for each of th...
Kriek NP, Kellerman TS, Marasas WF.An isolate of Fusarium verticillioides (MRC826) that induced experimental leukoencephalomalacia, also caused acute toxicity when fed to pigs and administered per rumen fistula to sheep. Pigs developed severe pulmonary oedema while sheep manifested severe nephrosis and hepatosis. A less toxic isolate (F. verticillioides MRC602), fed to baboons, resulted in acute congestive heart failure or hepatic cirrhosis, depending on the dose. Both isolates were toxic to rats and caused similar lesions, namely, hepatic cirrhosis and intraventricular cardiac thrombosis.
Mehdizadeh Gohari I, Parreira VR, Nowell VJ, Nicholson VM, Oliphant K, Prescott JF.A role for type A Clostridium perfringens in acute hemorrhagic and necrotizing gastroenteritis in dogs and in necrotizing enterocolitis of neonatal foals has long been suspected but incompletely characterized. The supernatants of an isolate made from a dog and from a foal that died from these diseases were both found to be highly cytotoxic for an equine ovarian (EO) cell line. Partial genome sequencing of the canine isolate revealed three novel putative toxin genes encoding proteins related to the pore-forming Leukocidin/Hemolysin Superfamily; these were designated netE, netF, and netG. netE a...
Müller N, Welle M, Lobsiger L, Stoffel MH, Boghenbor KK, Hilbe M, Gottstein B, Frey CF, Geyer C, von Bomhard W.The present report describes a novel etiological agent of cutaneous leishmaniasis in horses that, at least for some cases, sporadically appeared as autochthonous infections in geographically distant regions of Germany and Switzerland. The infection was initially diagnosed upon clinical and immunohistological findings. Subsequent comparative sequence analysis of diagnostic PCR products from the internal transcribed spacer 1 (ITS1) of ssrRNA classified the respective isolates as neither Old World nor New World Leishmania species. However, four isolates subjected to molecular analyses all exhibit...
Rossdale PD, Hopes R, Digby NJ, offord K.An epidemiological study of wastage among racehorses was conducted in 1982 and 1983 among six stables, five of which were in Newmarket. The basis of the survey was the inability of horses to take part in cantering exercise as a result of injury or disease. The greatest number of days lost to training was caused by lameness (67.6 per cent) and respiratory problems (20.5 per cent). Conditions of the foot (19 pe cent), muscle (18 per cent), carpus (14 per cent), fetlock joints (14 per cent), tendons (10 per cent) and sore shins (9 per cent) were the major reasons for training days being lost in 1...
Pirie RS.Recurrent airway obstruction is a widely recognised airway disorder, characterised by hypersensitivity-mediated neutrophilic airway inflammation and lower airway obstruction in a subpopulation of horses when exposed to suboptimal environments high in airborne organic dust. Over the past decade, numerous studies have further advanced our understanding of different aspects of the disease. These include clarification of the important inhaled airborne agents responsible for disease induction, improving our understanding of the underlying genetic basis of disease susceptibility and unveiling the fu...
Cheevers WP, McGuire TC.Equine infectious anemia (EIA) is a chronic, relapsing infectious disease of horses caused by a nononcogenic retrovirus. Virus persists in infected animals for life and can be reliably detected by serologic tests that measure levels of antibody to the major structural protein of the virus. Periodic virus replication in macrophages leads to an immunologically mediated acute disease characterized primarily by severe anemia. Recrudescence of acute EIA is the result of antigenic variation of the surface glycoprotein of EIA virus. The frequency and severity of clinical episodes of EIA decrease in m...
Lyons S, Kapoor A, Sharp C, Schneider BS, Wolfe ND, Culshaw G, Corcoran B, McGorum BC, Simmonds P.Although the origin of hepatitis C virus infections in humans remains undetermined, a close homolog of this virus, termed canine hepacivirus (CHV) and found in respiratory secretions of dogs, provides evidence for a wider distribution of hepaciviruses in mammals. We determined frequencies of active infection among dogs and other mammals in the United Kingdom. Samples from dogs (46 respiratory, 99 plasma, 45 autopsy samples) were CHV negative by PCR. Screening of 362 samples from cats, horses, donkeys, rodents, and pigs identified 3 (2%) positive samples from 142 horses. These samples were gene...
Bond S, Léguillette R, Richard EA, Couetil L, Lavoie JP, Martin JG, Pirie RS.The term "equine asthma" has been proposed as a unifying descriptor of inflammatory airway disease (IAD), recurrent airway obstruction (RAO), and summer pasture-associated obstructive airway disease. Whilst the term will increase comprehensibility for both the lay and scientific communities, its biologic relevance must be compared and contrasted to asthma in human medicine, recognizing the limited availability of peer-reviewed equine-derived data, which are largely restricted to clinical signs, measures of airway obstruction and inflammation and response to therapy. Such limitations constrain ...
Ramsay JD, Evanoff R, Wilkinson TE, Divers TJ, Knowles DP, Mealey RH.Equine hepacivirus (EHCV; nonprimate hepacivirus) is a hepatotropic member of the Flaviviridae family that infects horses. Although EHCV is the closest known relative to hepatitis C virus (HCV), its complete replication kinetics in vivo have not been described, and direct evidence that it causes hepatitis has been lacking. In this study, we detected EHCV in 2 horses that developed post-transfusion hepatitis. Plasma and serum from these horses were used to experimentally transmit EHCV to 4 young adult Arabian horses, two 1-month-old foals (1 Arabian and 1 Arabian-pony cross), and 2 foals (1 Ara...
Lobsiger L, Müller N, Schweizer T, Frey CF, Wiederkehr D, Zumkehr B, Gottstein B.The present case report describes a novel etiological agent of cutaneous leishmaniasis that appears for the first time in a cow. A similar agent had recently been described as causing autochthonous infections in horses of Germany and Switzerland. The infection in the cow was initially diagnosed upon clinical and immunohistological findings. Subsequent comparative sequence analysis of diagnostic PCR products from the internal transcribed spacer 1 (ITS1) of ssrRNA classified the respective isolate as neither Old World nor New World Leishmania species, but yielded complete identity of the analyse...
Bryant NA, Rash AS, Russell CA, Ross J, Cooke A, Bowman S, MacRae S, Lewis NS, Paillot R, Zanoni R, Meier H, Griffiths LA, Daly JM, Tiwari A....Equine influenza virus (EIV) surveillance is important in the management of equine influenza. It provides data on circulating and newly emerging strains for vaccine strain selection. To this end, antigenic characterisation by haemaggluttination inhibition (HI) assay and phylogenetic analysis was carried out on 28 EIV strains isolated in North America and Europe during 2006 and 2007. In the UK, 20 viruses were isolated from 28 nasopharyngeal swabs that tested positive by enzyme-linked immunosorbent assay. All except two of the UK viruses were characterised as members of the Florida sublineage w...
Harr KE, Flatland B, Nabity M, Freeman KP.As all laboratory equipment ages and contains components that may degrade with time, initial and periodically scheduled performance assessment is required to verify accurate and precise results over the life of the instrument. As veterinary patients may present to general practitioners and then to referral hospitals (both of which may each perform in-clinic laboratory analyses using different instruments), and given that general practitioners may send samples to reference laboratories, there is a need for comparability of results across instruments and methods. Allowable total error (TEa ) is ...
Shin EK, Perryman LE, Meek K.The equine SCID defect is more severe than its murine counterpart in that SCID foals are incapable of forming either coding or signal joints, whereas SCID mice manifest normal signal joint formation. To determine the basis of this difference and whether DNA-dependent kinase, catalytic subunit (DNA-PK(CS)), is involved in signal joint formation, equine DNA-PK(CS) transcripts were cloned and sequenced from normal and SCID cell lines. In the mutant allele, a frame-shift mutation truncates the protein N terminal of the domain with homology to the phosphatidylinositol 3-kinase family resulting in c...
Couëtil LL, Hoffman AM, Hodgson J, Buechner-Maxwell V, Viel L, Wood JL, Lavoie JP.The purpose of this consensus statement is to provide a review of current knowledge and opinions concerning inflammatory airway disease (IAD) and to help practitioners differentiate IAD from heaves (or recurrent airway obstruction; RAO) and other inflammatory respiratory diseases of horses.
Cantile C, Di Guardo G, Eleni C, Arispici M.West Nile (WN) virus infection is a mosquito-borne flavivirosis endemic in Africa and Asia. Clinical disease is usually rare and mild and only in a few cases the infection causes encephalomyelitis in horses, fever and meningoencephalitis in man. We report here the clinical and pathological findings in an epidemic of the disease involving 14 horses from Tuscany, Italy. All cases were observed from August to October 1998. Affected horses showed ataxia, weakness paresis of the hindlimbs and, in 6 cases, there was paraparesis progressing to tetraplegia and recumbency within 2 to 9 days. Eight anim...
