The study of diseases in horses encompasses a wide range of conditions affecting equine health, including infectious diseases, metabolic disorders, and genetic abnormalities. These diseases can impact various systems within the horse, such as respiratory, gastrointestinal, and musculoskeletal systems, and can lead to significant health challenges. Research in this area focuses on understanding the pathophysiology, diagnosis, prevention, and treatment of equine diseases. Common diseases studied include equine influenza, equine herpesvirus, and laminitis. This page provides access to peer-reviewed research studies and scholarly articles that explore the etiology, clinical presentation, and management strategies of diseases in horses, contributing to the advancement of equine veterinary medicine.
Jennings JE.A 21-year-old Appaloosa mare was presented with a pigmented cutaneous mass at the base of the right side of the neck. The diagnosis of phaeohyphomycosis due to pigmented fungi, known as Pyrenophora phaeocomes and Drechslera nobleae, was made based on a histopathology report followed by polymerase chain reaction (PCR) and 18S rRNA gene sequencing. The mass was surgically excised with clean margins, which is usually curative. Une jument Appaloosa âgée de 21 ans a été présentée avec une masse cutanée pigmentée à la base du côté droit du cou. Le diagnostic de phæohyphomycose causée p...
Carfora V, Caprioli A, Grossi I, Pepe M, Alba P, Lorenzetti S, Amoruso R, Sorbara L, Franco A, Battisti A.A Methicillin-resistantStaphylococcus aureus(MRSA) was isolated in Italy from a pathological sample of a mare presenting chronic purulent sinusitis and that had undergone frontal-sinus surgery three months before. Humans, horses, dogs and environmental samples were subsequently collected at the mare's stable and at the Veterinary Hospital, where the mare was operated/hospitalized, and screened for the presence of MRSA that was detected from other horses and from the environment at both sites. All the MRSA isolates belonged to clonal complex (CC)8, ST8-t11469-SCCmec-IVa, and showed similar phen...
Mort JS, Beaudry F, Théroux K, Emmott AA, Richard H, Fisher WD, Lee ER, Poole AR, Laverty S.To characterize the initial events in the cleavage of type II collagen mediated by cathepsin K and demonstrate the presence of the resulting products in human and equine articular osteoarthritic cartilage. Equine type II collagen was digested with cathepsin K and the cleavage products characterized by mass spectrometry. Anti-neoepitope antibodies were raised against the most N-terminal cleavage products and used to investigate the progress of collagen cleavage, in vitro, and the presence of cathepsin K-derived products in equine and human osteoarthritic cartilage. Six cathepsin K cleavage sit...
Axling JM, Castle K, Velie BD, Tammen I, Thomson PC, Hamilton NA, Raadsma HW, Lindgren G, Jeffcott LB, Nicholas FW.Diagnostic reports written to assist stud managers in the sale of young Thoroughbreds have not previously been used as a data source for the study of skeletal lesions. However, analyses of these reports may provide efficient and cost-effective insights into the prevalence and distribution of skeletal lesions within a population. Diagnostic reports written by veterinarians were acquired from Thoroughbred stud managers in Australia and New Zealand. The reports were based on approximately 1300 sets of weanling and yearling radiographs taken between 2002 and 2007. The prevalence and anatomical dis...
Ayala-Valdovinos MA, Galindo-García J, Sánchez-Chiprés D, Duifhuis-Rivera T.Lethal white foal syndrome (LWFS) is an autosomal recessive disease of neonatal foals characterized by a white hair coat and a functional intestinal obstruction. Traditional techniques for identifying the dinucleotide mutation (TC→AG) of the endothelin receptor B gene (EDNRB) associated with LWFS are time-consuming. We developed a new technique based on mutagenically separated polymerase chain reaction (MS-PCR) for simple detection of the EDNRB genotype in horses.
Barr B.Diarrhoea is a common problem in the neonatal and suckling foal. In certain circumstances supplemental nutrition is necessary depending on the age of foal, severity of diarrhoea and presence of other systemic manifestations. Nutritional supplementation can be provided either enterally or parenterally. Enteral nutrition is superior to parenteral nutrition because it is the most natural and physiologically sound means to provide nutritional support. Parenteral nutrition may be warranted if the foal is unable to receive or tolerate enteral nutrition. Dextrose alone or with amino acids and lipids ...
Erol E, Jackson C, Horohov D, Locke S, Smith J, Carter C.Determination of fetal serum amyloid A (SAA) concentrations in aborted fetuses can provide valuable information regarding the infectious and/or inflammatory process of abortion in horses. To investigate the relationship between fetal SAA levels and the infectious/inflammatory disease process in feto-placental tissues, a SAA ELISA was used to test heart serum samples of 89 equine fetuses that were necropsied and diagnosed in the following groups: a multiorgan disease process diagnosed with an identified microorganism (14 cases, group 1); only placentitis diagnosed with an identified microorgan...
Natali AN, Carniel EL, Frigo A, Pavan PG, Todros S, Pachera P, Fontanella CG, Rubini A, Cavicchioli L, Avital Y, De Benedictis GM.What is the central question of this study? Prostheses for treatment of urinary incontinence elicit complications associated with an inadequate mechanical action. This investigation aimed to define a procedure addressed to urethral mechanical characterization. Experimental tests are the basis for constitutive formulation, with a view to numerical modelling for investigation of the interaction between the tissues and a prosthesis. What is the main finding and its importance? Horse urethra, selected for its histomorphometric similarity to human urethra, was characterized by integrated histologic...
Wang Y, Mao Q, Chang H, Wu Y, Pan S, Li Y, Zhang Y.Integrins can function as receptors for foot-and-mouth disease virus (FMDV) in epithelium. Horses are believed to be insusceptible to this disease, but the mechanism of resistance remains unclear. To detect whether FMDV can use integrin to attach to equine epithelial, we compared the utilities of αvβ3 and αvβ6 between bovine and equine kidney epithelial cells (KECs). Equine KECs showed almost equal efficiency to those of bovine. Further, the integrin αv, β3, and β6 subunits from bovine and equine were cloned and vectors were transfected into SW480 cells and COS-1 cells alone or together...
Diyes GC, Rajakaruna RS.Otobius megnini is a one host, nidicolous soft tick (Family Argasidae) whose larvae and nymphs parasitize the external ear canal of many wild and domestic animals and occasionally humans. The present study was conducted to determine the seasonal dynamics of O. megnini infesting stabled horses in Nuwara Eliya racecourses. Ticks were sampled biweekly for two years from May 2013 to May 2015 from the ear canal of seven thoroughbred male horses. Weather data: temperature, rainfall and humidity for the study period were obtained from the Meteorological Department, Colombo. A total of 23, 287 ticks o...
Chindera K, Mahato M, Sharma AK, Horsley H, Kloc-Muniak K, Kamaruzzaman NF, Kumar S, McFarlane A, Stach J, Bentin T, Good L.To combat infection and antimicrobial resistance, it is helpful to elucidate drug mechanism(s) of action. Here we examined how the widely used antimicrobial polyhexamethylene biguanide (PHMB) kills bacteria selectively over host cells. Contrary to the accepted model of microbial membrane disruption by PHMB, we observed cell entry into a range of bacterial species, and treated bacteria displayed cell division arrest and chromosome condensation, suggesting DNA binding as an alternative antimicrobial mechanism. A DNA-level mechanism was confirmed by observations that PHMB formed nanoparticles whe...
Westermann CM, van Leeuwen R, van Raamsdonk LW, Mol HG.Atypical myopathy (AM) in horses is caused by the plant toxin hypoglycin A, which in Europe typically is found in the sycamore maple tree (Acer pseudoplatanus). Owners are concerned about whether their horses are in danger if they graze near maple trees. Objective: To measure hypoglycin A in the most common maple tree species in the Netherlands, and to determine whether concentration of toxin is a predictor of AM in horses. Methods: A total of 278 samples of maple tree leaves, sprouts, and seeds were classified by species. Mean concentrations of hypoglycin A were compared for the type of sampl...
Alves Beuttemmüller E, Woodward A, Rash A, Dos Santos Ferraz LE, Fernandes Alfieri A, Alfieri AA, Elton D.An extensive outbreak of equine influenza occurred across multiple countries in South America during 2012. The epidemic was first reported in Chile then spread to Brazil, Uruguay and Argentina, where both vaccinated and unvaccinated animals were affected. In Brazil, infections were widespread within 3months of the first reported cases. Affected horses included animals vaccinated with outdated vaccine antigens, but also with the OIE-recommended Florida clade 1 strain South Africa/4/03. Methods: Equine influenza virus strains from infected horses were isolated in eggs, then a representative stra...
Kováts N, Horváth E, Jancsek-Turóczi B, Hoffer A, Gelencsér A, Urbán P, Kiss ÍE, Bihari Z, Fekete C.Air quality in the stables is characterized by elevated level of dust and aeroallergens which are supposed to directly cause or exacerbate several respiratory disorders. The most often recognized problem is recurrent airway obstruction (RAO), previously known as chronic obstructive pulmonary disease (COPD). There is some indication that aeroallergens (among them endotoxins) may also cause inflammation in human airways and may exceed safe levels in stables. Monitoring studies have covered mainly the determination of the concentration of respirable particles and of culturable fungi and their tox...
Hue ES, Fortier CI, Laurent AM, Quesnelle YF, Fortier GD, Legrand LJ, Pronost SL.The protocol describes a quantitative RT-PCR method for the detection and quantification of EHV-2 in equine respiratory fluids according to the NF U47-600 norm. After the development and first validation step, two distinct characterization steps were performed according to the AFNOR norm: (a) characterization of the qRT-PCR assay alone and (b) characterization of the whole analytical method. The validation of the whole analytical method included the portrayal of all steps between the extraction of nucleic acids and the final PCR analysis. Validation of the whole method is very important for vi...
Cruz F, Fores P, Mughini-Gras L, Ireland J, Moreno MA, Newton JR.Equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4) have a worldwide distribution and cause respiratory disease, abortion, neonatal death and myeloencephalopathy in susceptible horses. Given the scarcity of serological EHV-1/EHV-4 data in Spain, the objective of this cross-sectional study was to estimate the seroprevalence of EHV-1/EHV-4 and to identify potential horse-level and stud farm-level factors associated with EHV-1/EHV-4 in the breeding Spanish Purebred (SP) horse population in central Spain. Serum samples from 334 SP unvaccinated horses, collected between September 2011 and November...
Lyle-Dugas J, Giguère S, Mallicote MF, Mackay RJ, Sanchez LC.Neonatal encephalopathy is the most common neurological abnormality identified in neonatal foals, but its clinical course has been rarely characterised. Objective: To describe factors associated with nonsurvival in a population of foals diagnosed with neonatal encephalopathy. Methods: Retrospective cross-sectional clinical study. Methods: Cases were selected from equine neonatal (≤14 days of age) admissions between 1996 and 2007. Multivariable logistic regression was used to identify clinical parameters, laboratory variables and therapeutic interventions associated with nonsurvival. Results:...
Saey V, Ploeg M, Delesalle C, van Loon G, Gröne A, Ducatelle R, Duchateau L, Chiers K.Rupture of the aorta is much more common in Friesians compared with other breeds of horse. Rupture always occurs adjacent to the scar of the ligamentum arteriosum. Previous histological examination of ruptured aortic walls suggested the presence of an underlying connective tissue disorder. Therefore, the aim of the present study was to compare the structural characteristics of the tunica media of the mid-thoracic aorta, distant to the lesion, in warmblood and Friesian horses with and without thoracic aortic rupture. In unaffected Friesian horses, the thickness of the tunica media, as well as t...
Roy Chowdhury P, DeMaere M, Chapman T, Worden P, Charles IG, Darling AE, Djordjevic SP.Clostridium difficile infections (CDI) are a significant health problem to humans and food animals. Clostridial toxins ToxA and ToxB encoded by genes tcdA and tcdB are located on a pathogenicity locus known as the PaLoc and are the major virulence factors of C. difficile. While toxin-negative strains of C. difficile are often isolated from faeces of animals and patients suffering from CDI, they are not considered to play a role in disease. Toxin-negative strains of C. difficile have been used successfully to treat recurring CDI but their propensity to acquire the PaLoc via lateral gene transfe...
Liebenberg D, Piketh S, van Hamburg H.Africa horse sickness (AHS) is the most lethal infectious non-contagious horse disease and has accordingly been declared notifiable by the World Organisation for Animal Health. AHS is endemic to sub-Saharan Africa and causes considerable losses to the equestrian industry. The effect of diseases in livestock on socio-economic factors is well researched, but the effect of anthropogenic factors on the distribution of a disease is poorly understood. The purpose of the study was to assess Namibian and South African horse owners' perceptions and the effect of horse movement on AHS distribution. A cr...
Mendoza L, Lejeune JP, Caudron I, Detilleux J, Sandersen C, Deliège B, Serteyn D.Osteochondrosis dissecans (OCD) is a developmental orthopedic disease caused by a failure of the endochondral ossification in epiphyseal plates and joint cartilage. This trouble may induce the presence of osteochondral fragments in the articulation, fissures or subchondral bone cysts in the growth cartilage. Occurrence of osteochondrosis is influenced by a complex interaction of different factors. Among these, the effect of the housing and the feeding of the foals during their first months of life, have been described as risk factors for the development of osteochondrosis. The aim of this stud...
Campbell MLH.This paper assesses whether cloning horses is ethical by reviewing ethical arguments against cloning of nonequine species and determining whether they apply to horses, analysing ethical arguments about horse cloning which do not apply to noncompetitive species and considering the ethical dilemmas faced by veterinarians involved in horse cloning. The author concludes that concerns about the health and welfare of cloned horses render the technique ethically problematic and that the onus is on those providing commercial equine cloning services to collate data and provide a stronger evidence base ...
Hurley MJ, Riggs CM, Cogger N, Rosanowski SM.A 2 year prospective study was performed between February 2011 and January 2013 to determine the incidence and risk factors for shipping fever (SF) in horses transported by air to Hong Kong (HK). Using a questionnaire, data were collected from professional flying grooms regarding the journey to HK and horses in the shipment. Horses were monitored in quarantine for 2 weeks after arrival in HK, and clinical signs of SF recorded. Poisson and logistic regression models were used to identify risk factors for SF at the horse and shipment levels. The study analysed data from 869 horses on 81 flights ...
Durán MC, Marqués FJ.A horse with colitis from Manitoba referred to the Veterinary Medical Centre, Western College of Veterinary Medicine, was diagnosed with Potomac horse fever (PHF). Polymerase chain reaction analysis of the feces confirmed Neorickettsia risticii infection. This is the first reported case of PHF in Manitoba. Détection deNeorickettsia risticii,agent de la fièvre du Potomac, chez un étalon Gypsy Vanner du Manitoba. Un diagnostic de fièvre du Potomac a été posé pour un cheval du Manitoba atteint de colite qui avait été recommandé au Veterinary Medical Centre du Western College of Veterina...
Mullen KR, Yasuda K, Divers TJ, Weese JS.While certainly not a novel concept, faecal microbiota transplant (FMT) has recently garnered renewed interest in veterinary medicine due to its remarkable success in treating recurrent Clostridium difficile infection (CDI) in man. There is a dearth of information on indications and efficacy of FMT for the treatment of gastrointestinal disorders in the horse; however, based on evidence in man and other veterinary species, and anecdotal reports in horses, FMT may be a useful treatment for selected cases of acute and chronic diarrhoea and inflammatory bowel disease (IBD) in the horse. In the abs...
Skotarczak B, Wodecka B, Rymaszewska A, Adamska M.Ixodes ricinus has the potential to transmit zoonotic pathogens to humans and domestic animals. The feeding I. ricinus (n = 1737) collected from 49 Shetland ponies and questing ones from vegetation (n = 371) were tested for the presence and differentiation of the bacterial species. DNA of I. ricinus ticks was examined with PCR and sequencing analysis to identify species of Borrelia burgdorferi sensu lato (Bbsl), Anaplasma phagocytophilum and Rickettsia spp. Altogether, 24.3 % I. ricinus of the infested horses and 12.4 % ticks from vegetation carried at least one pathogen species. Horse-f...
Gülegen E, Girisgin O, Girisgin AO, Cirak VY.The aim of the present study was to examine sport horses in Northwest Turkey for Eimeria (E.) leuckarti infections. Between 2004 and 2008 fecal samples from 549 horses of different age, breed and sex of 21 farms were examined for E. leuckarti oocysts using a qualitative method which involved centrifugation/flotation and saturated sugar solution as medium. The prevalence of infection was evaluated relative to host age, sex, breed and pasture availability. 16 (2.9%) horses were found to be infected with E. leuckarti, whilst infected horses were located in nine (42.8%) farms. Younger horses (<...
Oliver J, Lukacik G, Kramer LD, Backenson PB, Sherwood JA, Howard JJ.In New York State (NYS), Eastern equine encephalitis (EEE) was first reported in a human in 1971, in horses in 1970, and in pheasants in 1952. Methods: Following work for the interval from 1970 to 1991, we identified cases in vertebrates from 1992 to 2012, through a passive surveillance system involving veterinarians in clinical practice, county health departments, and the Departments of Agriculture and Markets, Environmental Conservation, and Health, of the State of New York. Results: During an 11-year hiatus, from 1992 to 2002, no case in any vertebrate was observed. In a re-emergence, from ...
Geiser DR.There are several beneficial physiologic and therapeutic effects of hyperbaric oxygen therapy (HBOT). The indications list for the use of HBOT in the horse has been developed through extrapolation from a review of human indications and from anecdotal clinical experiences. Hyperbaric therapy is a safe treatment option with very few side effects when administered properly.
Southwood LL, Schott HC, Henry CJ, Kennedy FA, Hines MT, Geor RJ, Hassel DM.Thirty-five cases of disseminated hemangiosarcoma (21 clinical cases and 14 previously reported cases) were reviewed to describe the disease in horses. Hemangiosarcoma occurred in mature, particularly middle-aged horses, with no apparent sex predilection. Thoroughbreds seemed to be overrepresented (13 cases) but a true breed predilection could not be established. The respiratory and musculoskeletal systems were most commonly affected and presenting complaints included dyspnea (26%), subcutaneous or muscular swelling (24%), epistaxis (17%), and lameness (12%). Heart and respiratory rates were u...
Equine arteritis virus (EAV) is the causative agent of equine viral arteritis (EVA), a respiratory and reproductive disease of equids. There has been significant recent progress in understanding the molecular biology of EAV and the pathogenesis of its infection in horses. In particular, the use of contemporary genomic techniques, along with the development and reverse genetic manipulation of infectious cDNA clones of several strains of EAV, has generated significant novel information regarding the basic molecular biology of the virus. Therefore, the objective of this review is to summarize cur...
Madsen M, Christensen P.Semen samples were collected from 21 Danish Warmblood stallions by the Colorado artificial vagina (Colorado AV, 14 samples) or by the Missouri artificial vagina (Missouri AV, 7 samples). The semen was examined bacteriologically by direct plating (DP) on blood agar plates, and by plating of semen swabs stored in Stuart's transport media (TM) at 4 degrees C for 1-4 days. No significant differences were observed between results obtained by DP and cultures of identical TM samples. Of the 21 samples examined, only 1 TM (4.8%) and 2 DP samples (9.5%) were sterile, while the rest yielded a predominan...
Bannai H, Nemoto M, Tsujimura K, Yamanaka T, Kondo T, Matsumura T.Virus-neutralizing (VN) testing is essential for evaluating virus-specific immunity in equine herpesvirus type-1 (EHV-1) infection. We developed a focus-reduction neutralization test (FRNT) for EHV-1 using 96-well plates for faster large-scale testing with sufficient sensitivity. We used an overlay medium containing Avicel (FMC Biopolymer), a microcrystalline cellulose with lower viscosity than the methylcellulose. The foci were visualized by immuno-staining with anti-EHV-1 gp14 monoclonal antibody. The FRNT successfully detected seroconversion in horses experimentally infected with EHV-1 (n =...
Magnuson NS, Perryman LE, Wyatt CR, Mason PH, Talmadge JE.Peripheral blood mononuclear cells from foals with hereditary severe combined immunodeficiency (SCID) have morphologic characteristics of large granular lymphocytes (LGL). Attempts to demonstrate cytotoxic activity were without success unless the LGL were incubated with 100 U of human recombinant interleukin 2 (rIL 2)/ml for 24 hr. With rIL 2 incubation, low effector to target ratios (10:1) consistently yielded high levels of cytotoxic activity (30 to 50%) in a standard 4-hr 51Cr-release assay using YAC-1 lymphoma or K562 erythroleukemia cell lines as targets. Monoclonal antibody EqT12 reacted...
Gillespie CC, Adams SB, Moore GE.To determine common methods for intra-articular injections and variables associated with the risk of septic arthritis following intra-articular injection in the horse. Methods: Cross-sectional survey. Methods: Equine veterinarians. Methods: A link to an online survey was distributed to equine practitioners in 2014. Responses for descriptive data were tabulated. Data on infection rates obtained from medical records were analyzed. Variables associated with the risk of septic arthritis were determined using χ or Fisher's exact tests and logistic regression. Results: Common current methods for in...
Wilkins PA, Palmer JE.Botulism has been recognized as a clinical entity in foals since the 1960s. Also known as "Shaker foal" disease, the toxicoinfectious form of botulism affects foals, with the highest incidence in the United States seen in Kentucky and the mid-Atlantic region. The disease is characterized by progressive muscular weakness caused by the action of botulism neurotoxin at cholinergic neuromuscular junctions. Increased number of episodes and duration of recumbency, muscular trembling, and dysphagia are seen in affected foals. Left untreated, the disease can be rapidly fatal, with death occuring secon...
Brinkschulte M, Bienert-Zeit A, Lüpke M, Hellige M, Ohnesorge B, Staszyk C.Sinusitis is a common disease in the horse. In human medicine it is described, that obstruction of the sinonasal communication plays a major role in the development of sinusitis. To get spatial sense of the equine specific communication ways between the nasal cavity and the paranasal sinuses, heads of 19 horses, aged 2 to 26 years, were analyzed using three-dimensional (3D) reformatted renderings of CT-datasets. Three-dimensional models were generated following manual and semi-automated segmentation. Before segmentation, the two-dimensional (2D) CT-images were verified against corresponding fr...
Grobbel M, Lübke-Becker A, Alesík E, Schwarz S, Wallmann J, Werckenthin C, Wieler LH.A total of 417 isolates of Escherichia coli collected from five animal species/organ system combinations from swine [urinary/genital tract (UGT) incl. mastitis metritis agalactia syndrome], horses [genital tract (GT)] and dogs/cats [respiratory tract (RT), UGT and gastrointestinal tract (GIT)] were analysed quantitatively for their susceptibility against different antimicrobial agents by determination of minimum inhibitory concentrations. Regardless of which animal species the strains originated from, resistance appeared most frequently against sulfamethoxazole (18-59%), tetracycline (14-54 %)...
Schrenk D, Bignami M, Bodin L, Del Mazo JKCJ, Grasl-Kraupp B, Hogstrand C, Leblanc JC, Nielsen E, Ntzani E, Petersen A, Sand S, Schwerdtle T....In 2017, the EFSA Panel on Contaminants in the Food Chain (CONTAM) adopted a Scientific Opinion on the risks for animal health related to the presence of deoxynivalenol (DON) and its acetylated and modified forms in food and feed. No observed adverse effect levels (NOAELs) and lowest observed adverse effect levels (LOAELs) were derived for different animal species. For horses, an NOAEL of 36 mg DON/kg feed was established, the highest concentration tested and not showing adverse effects. For poultry, an NOAEL of 5 mg DON/kg feed for broiler chickens and laying hens, and an NOAEL of 7 mg DO...
Vijarnsorn M, Riley CB, Shaw RA, McIlwraith CW, Ryan DA, Rose PL, Spangler E.To evaluate use of infrared spectroscopy for diagnosis of traumatic arthritis in horses. Methods: 48 horses with traumatic arthritis and 5 clinically and radiographically normal horses. Methods: Synovial fluid samples were collected from 77 joints in 48 horses with traumatic arthritis. Paired samples (affected and control joints) from 29 horses and independent samples from an affected (n = 12) or control (7) joint from 19 horses were collected for model calibration. A second set of 20 normal validation samples was collected from 5 clinically and radiographically normal horses. Fourier transfor...
Blunden AS, Smith KC, Whitwell KE, Dunn KA.A severe multi-systemic form of equid herpesvirus-1 infection is described in an adult zebra stallion. There was multifocal necrotizing rhinitis, marked hydrothorax and pulmonary oedema, with viral antigen expression in degenerating epithelial cells, local endothelial cells and intravascular leucocytes of the nasal mucosa and lung. Specific localization of EHV-1 infection was seen in the testes and epididymides, including infection of Leydig cells and germinal epithelium, which would have facilitated venereal shedding of virus in life. The case provided a unique opportunity to study hitherto u...
Claessen C, Favoreel H, Ma G, Osterrieder N, De Schauwer C, Piepers S, Van de Walle GR.Equid herpesvirus 1 (EHV1) is an ubiquitous alphaherpesvirus that can cause respiratory disease, abortion and central nervous disorders. EHV1 is known to infect a variety of different cell types in vitro, but its tropism for cultured primary equine mesenchymal stem cells (MSC) has never been explored. We report that equine MSC were highly permissive for EHV1 and supported lytic replication of the virus in vitro. Interestingly, we observed that an infection of MSC with EHV1 resulted in a consistent downregulation of cell surface molecules CD29 (β1-integrin), CD105 (endoglin), major histocompat...
Stannard AA, Cello RM.In a study of Onchocerca cervicalis infection in a sample of 100 horses from the western United States, 48 were infected. Infection was more common in older horses and occurred in both sexes equally. Data about the distribution and the concentration of microfilariae within the skin are presented. The only cutaneous pathologic change that could be attributed to microfilariae was minimal perivascular inflammatory cell infiltrate. Invasion of the eye with microfilariae occurred in 60 percent of the infected horses. An attempt was not made to relate microfilarial invasion of the eye with ocular pa...
Giles CJ.Five out of 20 horses (25 per cent) on one farm died from an acute hepatic encephalopathy typical of ragwort toxicosis. Circumstantial evidence implicated pasture rather than hay as the principal source of the toxic alkaloids. Plasma levels of gamma glutamyl transferase (GGT) were determined on three occasions in all surviving ragwort-exposed horses. Elevated GGT levels were a useful early indicator of hepatic damage although not all horses with this biochemical sign developed clinical disease.
Schwartz EJ, Vaidya NK, Dorman KS, Carpenter S, Mealey RH.Understanding the dynamics of acute viral infection is crucial for developing strategies to prevent and control infection. In this study, lentiviral dynamics in a host without adaptive immunity were examined in order to determine kinetic parameters of infection and quantify the effect of neutralizing antibodies in preventing infection, using mathematical modeling of data from equine infectious anemia virus (EIAV) infection of horses with severe combined immunodeficiency (SCID). Estimated parameters were used to calculate the basic reproductive number and virus doubling time and found that the ...
Brown JJ, Thomson W, Clegg P, Eyre S, Kennedy LJ, Matthews J, Carter S, Ollier WE.The full extent of the polymorphism of ELA-DRA in Equidae is not yet known. Given the apparent differences in DRA polymorphisms between Equidae and other species, the aims of this study were to more fully characterize ELA-DRA, determine the extent of gene polymorphism and establish the allele-frequency distribution. An allele reference panel for the second exon of ELA-DRA was established by sequence-based typing of 69 equine DNA samples consisting of various breeds of domestic horse (Equus caballus), together with donkeys (Equus asinus), Grant's zebras (Equus boehmi) and one onager (Equus hemi...
Findley JA, Pinchbeck GL, Milner PI, Bladon BM, Boswell J, Mair TS, Suthers JM, Singer ER.The factors associated with outcome following solar foot penetration involving synovial structures treated using endoscopic lavage have not been described in the UK population. Objective: To provide descriptive data on horses with synovial contamination or sepsis following solar penetration in 4 UK equine referral hospitals and to identify specific factors associated with the outcome. Methods: Retrospective case series. Methods: Data were collected from 4 veterinary hospitals. Follow-up data were obtained via a telephone questionnaire. Two multivariable logistic regression models were generate...
Nemoto M, Tsujimura K, Yamanaka T, Kondo T, Matsumura T.Loop-mediated isothermal amplification (LAMP) is a novel method for the rapid and sensitive detection of DNA without the need for expensive equipment. In the present study, LAMP assays were developed for the specific detection of Equid herpesvirus 1 and 4 (EHV-1 and EHV-4, respectively) and for the differentiation of glycoprotein E (gE)-deleted EHV-1 (DeltagE) strain, a candidate strain for a live vaccine, from field EHV-1 strains. Specific primer sets were designed for the gC and gE genes of EHV-1 and for the gC gene of EHV-4. The analytical sensitivities of the LAMP assays were compared with...
Whitfield-Cargile CM, Cohen ND, Suchodolski J, Chaffin MK, McQueen CM, Arnold CE, Dowd SE, Blodgett GP.In equids, susceptibility to disease caused by Rhodococcus equi occurs almost exclusively in foals. This distribution might be attributable to the age-dependent maturation of immunity following birth undergone by mammalian neonates that renders them especially susceptible to infectious diseases. Expansion and diversification of the neonatal microbiome contribute to development of immunity in the gut. Moreover, diminished diversity of the gastrointestinal microbiome has been associated with risk of infections and immune dysregulation. We thus hypothesized that varying composition or reduced div...
Lykkjen S, Olsen HF, Dolvik NI, Grøndahl AM, Røed KH, Klemetsdal G.The pathogenesis of osteochondrosis (OC) and palmar/plantar first phalanx osteochondral fragments (POFs) is multifactorial, but specific knowledge of heritability is limited. Objective: To improve the precision of heritability estimates and to estimate the genetic correlation between tarsocrural OC and POFs in Standardbred trotters. Further aims were to examine whether the prevalence of OC/POFs was different in the American and French lineages that have contributed to the Norwegian population, and if the prevalence was affected by heterozygosity. Methods: Retrospective cohort study. Methods: C...
Thiemann AK, Sullivan RJE.A review of common gastrointestinal disorders of donkeys and mules is presented. Clinically relevant aspects of donkey behavior, anatomy, and physiology are highlighted. Diagnosis, management, and treatment of conditions affecting the gastrointestinal tract from stomach to rectum, including liver and pancreas, are discussed.
Spence KL, Cardwell JM, Slater J, Rosanowski SM.The potential for an exotic disease incursion is a significant concern for the United Kingdom (UK) equine industry. Horse owners' perceptions of, and attitudes towards, exotic diseases can influence decisions to adopt disease preparedness strategies. The objectives of this study were to describe horse owners' 1) perceptions of the term 'exotic disease', and 2) attitudes towards their risk of being affected by an exotic disease. In order to address these objectives, qualitative content analysis was undertaken on data collected using two open-ended survey questions. Results: Horse owners (n =...
Williams A, Christley RM, McKane SA, Roberts VL, Clegg PD, Williams NJ.The aim of this study was to determine whether hospitalisation of horses leads to increased antimicrobial resistance in equine faecal Escherichia coli isolates. E. coli were cultured from faecal samples of horses on admission and after 7 days of hospitalisation; antimicrobial susceptibility was determined for eight antimicrobial agents. Resistance profiles of E. coli isolates were grouped into clusters, which were analysed to determine resistance patterns. Resistance to 7/8 antimicrobial agents and multi-drug resistance (MDR; resistance to ≥3 antimicrobial classes) were significantly higher ...
Labelle AL, Hamor RE, Townsend WM, Mitchell MA, Zarfoss MK, Breaux CB, Thomasy SM, Hall T.To determine types and frequency of ophthalmic lesions detected in neonatal foals evaluated for nonophthalmic disease at 3 veterinary referral hospitals and to investigate associations between systemic and ophthalmic diseases in these foals. Methods: Prospective cross-sectional study. Methods: 70 foals < 30 days old. Methods: Complete ophthalmic examinations were performed. Signalment, clinical signs, mentation during ophthalmic examination, results of clinicopathologic tests, and diagnosis of systemic disease were recorded. Descriptive data analysis including a χ(2) test for associations was...
Cope SE, Catts EP.Parahost behavior of adult Gasterophilus intestinalis (DeGeer) was observed during the summers of 1978 and 1979 near pastured horses on two farms near Newark, Del. Adult fly occurrence, although sparse in early summer, indicated a gradual increase, with three surges in emergence. In the laboratory, males lived 1-3 d and females 1-2 d. In the field, marked flies were not seen on days following their release. Adult behavior indicated an urgency in mating and oviposition dictated by a short life span. Male flight patterns were characterized by in-flight searches for females and intraspecific conf...
Adams AP, Oriol JG, Campbell RE, Oppenheim YC, Allen WR, Antczak DF.This research tested the hypothesis that immunological sensitization of mares by skin allografting, followed by the establishment of pregnancy using semen from the skin-graft donor, would give rise to secondary immune responses to the developing horse conceptus, resulting in an earlier demise of the fetally derived endometrial cups. Maiden mares received skin allografts from a stallion homozygous for Major Histocompatibility Complex (MHC) antigens and/or equivalent autografts and were subsequently mated to the skin-graft donor stallion during the next two breeding seasons. Mares that had been ...
Ranz AI, Miguet JG, Anaya C, Venteo A, Cortés E, Vela C, Sanz A.A panel of 32 hybridoma cell lines secreting monoclonal antibodies (MAbs) reactive with African horsesickness virus serotype 4 (AHSV-4) has been developed. Four of the MAbs recognized the major core antigen VP7, twenty recognized the outer capsid protein VP2 and eight reacted with the non-structural protein NS1. With the VP7-specific MAbs a rapid and sensitive double antibody sandwich immunoassay has been developed to detect viral antigen in infected Vero cells and in spleen tissue from AHSV-infected horses. The sensitivity of the assay is 10 ng viral antigen per 100 microliters. The NS1-speci...
Larson EM, Wagner B.Horses have many naturally occurring diseases that mimic similar conditions in humans. The ability to conduct environmentally controlled experiments and induced disease studies in a genetically diverse host makes the horse a valuable intermediate model between mouse studies and human clinical trials. This review highlights important similarities in the immune landscape between horses and humans using current research on two equine diseases as examples. First, equine herpesvirus type 1 (EHV-1) infection initiates a series of innate inflammatory signals at its mucosal entry site in the upper res...
Sun C, Zhang B, Jin J, Montelaro RC.The identification and characterization of a functional cellular receptor for equine infectious anemia virus (EIAV), designated equine lentivirus receptor-1 (ELR1), a member of the tumour necrosis factor receptor protein family, has been reported previously [Zhang, B. et al. (2005). Proc Natl Acad Sci U S A, 102 , 9918-9923]. The finding of a single receptor for EIAV is distinct from feline, simian and human immunodeficiency viruses, which typically utilize two co-receptors for infection, but is similar to avian and murine oncoviruses, which use single receptors. This study sought to determine...