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.
Johnson AL, McAdams-Gallagher SC, Sweeney RW.Botulism in horses in the USA is attributed to Clostridium botulinum types A, B or C. In this study, a duplex quantitative real-time PCR (qPCR) for detection of the neurotoxin genes of C. botulinum types A and B, and a singleplex qPCR for detection of the neurotoxin gene of C. botulinum type C, were optimized and validated for equine gastrointestinal, faecal and feed samples. The performance of these assays was evaluated and compared to the standard mouse bioassay (MBA) using 148 well-characterized samples, most of which were acquired from a repository of veterinary diagnostic samples from cas...
Arroyo LG, Ter Woort F, Baird JD, Tatiersky L, Delay J, van Dreumel T.This report describes 5 cases of fatal Lawsonia intracellularis-associated ulcerative and necro-hemorrhagic enteritis in weanling Thoroughbred and Standardbred foals. The lesions are similar to those of the L. intracellularis-associated ulcerative and necro-hemorrhagic enteritis syndrome in pigs. Two foals had concurrent severe typhlo-colitis as a result of a large burden of encysted cyathostomes. The clinical, diagnostic, and therapeutic challenges, and the potential complications encountered during the management of such cases are discussed. Entérite ulcérative et nécro-hémorragique asso...
Furness MC, Snyman HN, Abrahams M, Moore A, Vince A, Anderson ME.A 13-year-old Percheron gelding was presented for refractory gastric impaction. At necropsy a pedunculated 10 cm × 11 cm × 14 cm mass, histologically identified as an inflammatory polyp, was suspected to have been partly obstructing the pylorus. This is the first report of a polyp resulting in gastric outflow obstruction in a horse. Un hongre Percheron âgé de 13 ans a été présenté pour une surcharge gastrique réfractaire. À la nécropsie, une masse pédonculée de 10 cm × 11 cm × 14 cm, identifiée à l’histologie comme un polype inflammatoire, a été soupçonnée d’avoir par...
Baird JD, Arroyo LG.In the summer of 1924 Dr. Frank W. Schofield conducted investigations into an endemic disease of horses in the Kent and Essex counties of Ontario. According to farmers in these counties the disease had existed in this region for at least 50 years previously. The clinical, pathological, histopathological, and epidemiological findings outlined in Schofield's detailed report strongly suggest that this endemic disease was what was designated in 1979 as "Potomac horse fever" (PHF). This assumption is further substantiated by transmission experiments involving horses and laboratory animals that were...
Leadon DP, Jeffery R, O'Toole D, Duggan V.This report compiles the available information on unwanted horses in Ireland for 2011 and 2012 and builds upon the previous report for the period 2005 to 2010. Similar trends are present in the high value responsible ownership category and the practicing veterinary profession although extensively involved in horse welfare, euthanises a small proportion of Ireland's unwanted horses. Welfare groups have limited resources and a limited ability to deal with such an extensive problem, which has involved very large numbers of horses. Local authorities continue to have to devote significant efforts a...
Swerczek TW.Reports of 148 cases of Tyzzer's disease in foals in central Kentucky were analyzed to identify features of the disease and factors associated with it. The records indicate that Tyzzer's disease is a rapidly progressive, highly fatal hepatitis caused by Clostridium piliforme. Common clinical findings are lethargy, fever, anorexia, and icterus. Seizures, coma, and death may rapidly ensue. Laboratory findings are leukopenia, metabolic acidosis, hypoglycemia, and increased activity of hepatic enzymes. Diagnosis is primarily based on clinical signs and postmortem findings but a polymerase chain re...
Tatarniuk DM, Bracamonte JL, Wilson DG, Sharma A, Perry AW.A 6-year-old Canadian Warmblood gelding was presented for suspicion of keratoma growth, based on a history of recurring abscesses in the right front foot. Radiographic examination and computed tomography identified 2 bilaterally symmetrical, laminar epidermal ingrowths adhered to the hoof wall at the level of the lateral and medial heels. Hyperplasie épidermique laminaire et hyperkératose dans un sabot équin. Un hongre Canadian Warmblood âgé de 6 ans a été présenté en raison de soupçons relativement à la croissance de kératomes, basés sur des antécédents d’abcès récurrents d...
Bishop RM, Scott I, Gee EK, Rogers CW, Pomroy WE, Mayhew IG.To ascertain whether resistance was present in Parascaris equorum to the macrocyclic lactone anthelmintic ivermectin, using faecal egg count reduction tests. Methods: Thirty-nine foals aged between 11 and 28 weeks on three Thoroughbred stud farms (Farms A; n=20, B; n=5 and C; n=14) were treated with ivermectin (Day 0) and faecal egg counts (FEC) were monitored before and for 21 (Farms A and B) or 14 (Farm C) days after treatment. On Farms A and B, the foals were treated with a macrocyclic lactone/benzimidazole/praziquantel combination on Day 21 and FEC assessed on Day 35. The three farms were ...
Sampieri F, Vannucci FA, Allen AL, Pusterla N, Antonopoulos AJ, Ball KR, Thompson J, Dowling PM, Hamilton DL, Gebhart CJ.Lawsonia intracellularis infection causes proliferative enteropathy (PE) in many mammalian species, with porcine and equine proliferative enteropathy (PPE and EPE) known worldwide. Hamsters are a well-published animal model for PPE infection studies in pigs. There is no laboratory animal model for EPE infection studies and it is not known whether there is species-specificity for equine or porcine isolates of L. intracellularis in animal models. The objective of this study was to determine whether it is possible to generate typical EPE lesions in hamsters after inoculation with an equine strain...
Van Eeden C, Zaayman D, Venter M.Recently Shuni virus (SHUV) has been identified in clinical cases of neurological disease in horses in South Africa. Being that it was one of the less recognized orthobunyaviruses, with limited clinical descriptions of disease dating back to the 1960s and 1970s, SHUV-specific assays were never developed. In this study, the development of a nested real-time PCR assay is described for the detection of SHUV by means of melt-curve analysis using fluorescence resonance energy transfer (FRET) probe technology. The assay was validated against previously positive clinical specimens and a dilution seri...
Sloet van Oldruitenborgh-Oosterbaan MM, Grinwis GC.Equine sarcoidosis seems to be an emerging problem. As more horses are referred for dermatologic disease, equine sarcoidosis should be considered in any case of exfoliative and/or nodular skin disease with or without systemic involvement, including generalized granulomatous disease affecting most internal organs. Multiple breeds are affected with mares being predisposed. Affected horses are typically 3 years or older. The prognosis for generalized granulomatous disease is generally poor, whereas the prognosis for the localized cutaneous form is favorable but may require lifelong treatment.
Wijnberg ID, van der Ree M, van Someren P.Short-duration electroencephalography (EEG) recordings in horses are helpful in diagnosing intracranial disorders. Potentially, long-duration ambulatory EEG (AEEG) recordings in horses will enhance the chance of detecting abnormal brain activity independent of the presence of an insult. Objective: The objective of this study was to test if AEEG recordings in unsedated horses can be acquired and benefit diagnosing abnormal brain activity. Methods: Recordings were taken from 8 adult control horses and 10 patients suspected of intracranial abnormalities. Self-adhesive electrodes and the 'Porti-5'...
Mazzei M, Savini G, Di Gennaro A, Macchioni F, Prati MC, Guzmàn LR, Tolari F.West Nile virus (WNV) is a mosquito-borne virus belonging to the family Flaviviridae included in the Japanese encephalitis antigenic complex (JEAC). A seroepidemiological study was carried out in 2011 using 160 horse sera collected from different areas of Bolivia to investigate the presence of WNV antibody. A high proportion (59.4%) of the tested sera were positive to a commercially available WNV competitive enzyme-linked immunosorbent assay (C-ELISA). Sixty-six randomly selected C-ELISA-positive sera were further tested by WNV plaque reduction neutralization test (PRNT), virus neutralization ...
Ziegler U, Skrypnyk A, Keller M, Staubach C, Bezymennyi M, Damiani AM, Osterrieder N, Groschup MH.West Nile virus (WNV) is a mosquito-borne virus of global importance. Over the last two decades, it has been responsible for significant numbers of cases of illness in humans and animals in many parts of the world. In Ukraine, WNV infections in humans and birds were first reported more than 25 years ago, yet the current epidemiological status is quite unclear. In this study, serum samples from over 300 equines were collected and screened in order to detect current WNV activity in Ukraine with the goal to estimate the risk of infection for humans and horses. Sera were tested by enzyme-linked im...
Boudreaux MK, Humphries DM.Platelet alloantigens in horses may play an important role in the development of neonatal alloimmune thrombocytopenia (NAIT). Objective: The objective of this study was to evaluate genes encoding major platelet glycoproteins within the Equidae family in an effort to identify potential alloantigens. Methods: DNA was isolated from blood samples obtained from Equidae family members, including a Holsteiner-Oldenburg cross, a Quarter horse, a donkey, and a Plains zebra (Equus burchelli). Gene sequences encoding equine platelet membrane glycoproteins IIb, IIIa (integrin subunits αIIb and β3), Ia (...
Riet-Correa F, Rivero R, Odriozola E, Adrien Mde L, Medeiros RM, Schild AL.In the current study, mycotoxicoses of ruminants and horses are reviewed, with an emphasis on the occurrence of these diseases in South America. The main mycotoxicoses observed in grazing cattle include intoxications by indole-diterpenoid mycotoxins (Paspalum spp. contaminated by Claviceps paspali, Lolium perenne infected by Neotyphodium lolii, Cynodon dactylon infected by Claviceps cynodontis, and Poa huecu), gangrenous ergotism and dysthermic syndrome (hyperthermia) caused by Festuca arundinacea (syn. Festuca elatior) infected by Neotyphodium coenophialum (syn. Acremonium coenophialum), and ...
Sampieri F, Allen AL, Pusterla N, Vannucci FA, Antonopoulos AJ, Ball KR, Thompson J, Dowling PM, Hamilton DL, Gebhart CJ.The objective of this study was to demonstrate the susceptibility of rabbits to Lawsonia intracellularis obtained from a case of clinical equine proliferative enteropathy (EPE). This is a preliminary step toward developing a rabbit infection model for studying pathogenesis and therapy of EPE in horses. Nine does were equally assigned to 3 groups. Animals in 2 groups (Group 1 and Group 2) were orally inoculated with different doses of cell-cultured L. intracellularis. Controls (Group 3) were sham-inoculated. Feces and blood were collected before the rabbits were infected and at 7, 14, and 21 da...
Biddle AS, Black SJ, Blanchard JL.Laminitis is a chronic, crippling disease triggered by the sudden influx of dietary starch. Starch reaches the hindgut resulting in enrichment of lactic acid bacteria, lactate accumulation, and acidification of the gut contents. Bacterial products enter the bloodstream and precipitate systemic inflammation. Hindgut lactate levels are normally low because specific bacterial groups convert lactate to short chain fatty acids. Why this mechanism fails when lactate levels rapidly rise, and why some hindgut communities can recover is unknown. Fecal samples from three adult horses eating identical di...
Mir IA, Kumar B, Taku A, Faridi F, Bhat MA, Baba NA, Maqbool T.Present study was undertaken to study the prevalence of β-haemolytic streptococci in equine of northern temperate region of Jammu and Kashmir, India. One hundred and forty one samples were collected in duplicate from nasopharyngeal tract of diseased (53) and apparently healthy equine (88) for isolation and direct PCR. A total of 77 isolates of streptococci were recovered from 141 samples with an overall prevalence rate of 54.60%. Out of these 77 isolates, 52 were from diseased and 25 from apparently healthy animals. Of the 77 isolates, 4 were identified as Streptococcus equi subsp. equi, 56 a...
Grosche A, Morton AJ, Graham AS, Polyak MM, Freeman DE.To determine the effect of large colon ischemia and reperfusion on concentrations of the inflammatory neutrophilic protein calprotectin and other clinicopathologic variables in jugular and colonic venous blood in horses. Methods: 6 healthy horses. Methods: Horses were anesthetized, and ischemia was induced for 1 hour followed by 4 hours of reperfusion in a segment of the pelvic flexure of the large colon. Blood samples were obtained before anesthesia, before induction of ischemia, 1 hour after the start of ischemia, and 1, 2, and 4 hours after the start of reperfusion from jugular veins and ve...
Misumi K, Vilim V, Clegg PD, Thompson CC, Carter SD.This study was designed to assay cartilage oligomeric matrix protein (COMP) in equine synovial fluids and to compare the concentration in synovial fluids from normal horses with joint diseased horses. The relationship between the COMP degradation and the matrix metalloproteinase activity in synovial fluids was also investigated. Methods: Using COMP antigen prepared from equine articular cartilage and murine monoclonal antibody (12C4) raised against human COMP, an inhibition ELISA was developed. COMP in equine synovial fluids from normal and diseased joints was quantified. Metalloproteinase act...
Shipton WA.The equine phycomycotic agent known commonly as Hyphomyces destruens or occasionally as Pythium gracile, is described as a new species Pythium destruens. Separation is on the basis of morphological features, temperature growth profiles, esterase/lipase activity, and carbohydrate utilization ability. P. diclinum (synonymous with P. gracile sensu Middleton) showed minor differences in vesicle, oospore and oogonium size from P. destruens. P. destruens grew at 40 degrees C on corn meal agar and hydrolysed esters of lauric and oleic acids. These abilities were not displayed by P. diclinum, but this...
Serteyn D, Deby-Dupont G, Pincemail J, Mottart E, Philippart C, Lamy M.Arachidonic acid cyclooxygenase metabolites, thromboxane B2 (TXB2), prostaglandin E2 (PGE2) and 6-keto-prostaglandin F1 (6-keto-PGF1) were measured in horses where anaesthesia was maintained with halothane. Two horses suffering from postanaesthetic myositis were compared with four normal horses. TXB2 and PGE2 levels were higher in mixed venous blood drawn from the myopathic horses. An increase of TXB2 and PGE2 levels appeared when myopathic horses were rolled into dorsal recumbency after a prolonged period of lateral recumbency. One hour after the end of anaesthesia, TXB2 had continued to incr...
de Keyser K, Janssens S, Buys N.The objective of this review was to summarise and evaluate the current state of knowledge about chronic progressive lymphoedema in draught horses. Clinical signs of this multifactorial disorder are mainly restricted to the lower limbs, comprising progressively deteriorating skin, swelling and deformation. Although typical lesions were first reported at the beginning of the 20th century, chronic progressive lymphoedema was recognised as a specific syndrome only in 2003, and since then research has driven forward. Despite the high prevalence in some breeds and the serious economic impact, the pa...
Charbonneau ARL, Taylor E, Mitchell CJ, Robinson C, Cain AK, Leigh JA, Maskell DJ, Waller AS.The availability of next-generation sequencing techniques provides an unprecedented opportunity for the assignment of gene function. subspecies is the causative agent of strangles in horses, one of the most prevalent and important diseases of equids worldwide. However, the live attenuated vaccines that are utilized to control this disease cause adverse reactions in some animals. Here, we employ transposon-directed insertion-site sequencing (TraDIS) to identify genes that are required for the fitness of in whole equine blood or in the presence of HO to model selective pressures exerted by th...
Madison JB, Reid BV, Raskin RE.Infectious arthritis caused by Candida spp was diagnosed in 2 horses. Source of infection was by direct inoculation in 1 horse and was presumed to be hematogenous in the other horse. On microbial culturing of synovial fluid and synovial membrane specimens, the organisms were isolated in both horses. In both horses, the joint infections resolved after i.v. administration of amphotericin B and joint drainage; however, 1 horse was eventually euthanatized because of signs of cervical pain and progressively worsening ataxia. Fungal organisms isolated on microbial culturing of joint specimens in hor...
Byars TD, Becht JL.The historical, clinical, diagnostic, and therapeutic aspects of pleuropneumonia are reviewed with emphasis placed on aggressive treatment and ultrasound diagnosis. The common sequelae are described, and appropriate treatment recommendations are included. A favorable prognosis may be expected for horses receiving long-term treatment.
Weese JS, Slovis N, Rousseau J.Understanding the epidemiology of Clostridium difficile is important for the development and assessment of infection prevention and control practices, as well as surveillance methods and interpretation of diagnostic testing results. Objective: Our objective was to longitudinally evaluate C. difficile shedding in neonatal foals and mares admitted to a referral hospital neonatal intensive care unit. Methods: Foals admitted to a neonatal intensive care unit, along with their dams. Methods: Rectal swabs were collected from mares and foals at admission, and then approximately every 3 days, when p...
Platt H.Abortion in the Thoroughbred mare has been studied from the standpoint of its statistical incidence and the factors that predispose to its occurrence. The pathological findings in a series of aborted foetuses submitted for autopsy are described. Some aspects of the aetiology of abortion in the mare are discussed.
Mainguy-Seers S, Diaw M, Lavoie JP.While the prevalence of asthma is higher in boys than in girls during childhood, this tendency reverses at puberty, suggesting an effect of sex hormones on the disease pathophysiology. Fluctuations of asthma severity concurring with the estrus cycle are reported in women, but this phenomenon has never been investigated in mares to date. The objective of this exploratory study was to determine whether the estrus cycle modulates airway obstruction in severe equine asthma (SEA). Five mares with SEA during exacerbation of the disease were studied. The whole breath, expiratory and inspiratory resis...
Soule C, Dupouy-Camet J, Georges P, Ancelle T, Gillet JP, Vaissaire J, Delvigne A, Plateau E.Three groups of three horses each were, respectively, infected with 5000, 20,000 and 50,000 larvae of Trichinella spiralis. The strain used was isolated from a human biopsy during horsemeat-related outbreaks of trichinellosis in France. Transient muscular disorders were only observed in two of the horses infected with 50,000 larvae but none of the horses had fever. A significant increase in blood eosinophils was noticed in 5 horses. Serum LDH, aldolase and CPK peaked at the fifth week post-infection. Specific IgG assayed by indirect immunofluorescence and ELISA, appeared 2-5 weeks post-infecti...
Frymus T, Kita J, Woyciechowska S, Ganowicz M.On 6 farms with a history of EHV-1 abortions the overall prevalence of losses due to abortion, stillbirth and neonatal foal mortality during 5 foaling seasons preceding the introduction of vaccination against EHV-1 were compared with corresponding data for 8 subsequent seasons in which all horses were immunized with a modified live EHV-1 vaccine. Although both sporadic and epizootic EHV-1 abortions occurred in immunized mares, the numbers of foetal and neonatal foal losses decreased significantly (chi 2 = 15.75; p less than 0.001) from 11.8% (343 of 2897 pregnancies) during the seasons 1969-19...
Clabough DL, Levine JF, Grant GL, Conboy HS.The records of 361 Standardbred mares and their 1986 or 1987 foals were evaluated to identify factors associated with failure of passive transfer (FPT) of colostral antibodies in equine neonates. Sixty-five foals (18%) were classified as FPT based on a serum immunoglobulin concentration of less than 400 mg/dl at 24 to 36 hours of age, determined by the glutaraldehyde coagulation test. The potential association of mare- and foal-related factors with FPT were assessed by reviewing a series of multiple logistic regression models. The season in which the mare foaled and foal exam score, a subjecti...
de Raat IJ, van den Boom R, van Poppel M, van Oldruitenborgh-Oosterbaan MM.Insect bite hypersensitivity (IBH) in horses is most likely caused by Culicoides species, although other insects may also play a role. Until now no effective cure has been found for this condition, although numerous therapeutic and preventive measures have been used to control insect hypersensitivity. One such method is to apply a topical insecticide to horses. In this study, the effect of a topical insecticide containing permethrin (3.6%) was examined in seven pairs of horses. The horses were placed inside a tent trap to collect Culicoides spp. and other insects attracted to the horses on two...
Sandstedt K, Engvall A.Sera from 116 and 89 Swedish pigs and horses respectively were examined for the presence of antibodies to L. bratislava. Antibodies were found in 18.1 and 49.4% respectively of pigs and horses examined. Presence of serum antibodies was not associated with clinical signs of infection.
Friend SC.Two horses died of massive myonecrosis following surgery. The hematological, biochemical and pathological changes are described and compared with those previously reported in the literature.