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.
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...
Esparza J.Mystery surrounds the extent to which horsepox virus may have contributed to the vaccinia virus used to eradicate smallpox. With few documented cases of horsepox in recent years it may never be solved, says José Esparza, who seeks to raise awareness of the potential historical and scientific importance of identifying new cases.
Duquesne F, Hébert L, Breuil MF, Matsuda M, Laugier C, Petry S.We describe here the development of a multilocus sequence typing (MLST) scheme for Taylorella equigenitalis, the causative agent of contagious equine metritis (CEM), and Taylorella asinigenitalis, a nonpathogenic bacterium. MLST was performed on a set of 163 strains collected in several countries over 35 years (1977-2012). The MLST data were analyzed using START2, MEGA 5.05 and eBURST, and can be accessed at http://pubmlst.org/taylorella/. Our results revealed a clonal population with 39 sequence types (ST) and no common ST between the two Taylorella species. The eBURST analysis grouped the 27...
Sanz M, Loynachan A, Sun L, Oliveira A, Breheny P, Horohov DW.While Rhodococcus equi remains the most common cause of subacute or chronic granulomatous bronchopneumonia in foals, development of a relevant model to study R. equi infection has proven difficult. The objective of this study was to identify a challenge dose of R. equi that resulted in slow progressive disease, spontaneous regression of lung lesions and age-dependent susceptibility. Foals less than one-week of age were challenged intratracheally using either 10(6), 10(5), 10(4), 10(3) or 10(2) cfu of R. equi. Two doses (10(3) cfu and 10(5) cfu) were used to challenge 2 and 3-week-old, and 3 an...
Marenzoni ML, Bietta A, Lepri E, Casagrande Proietti P, Cordioli P, Canelli E, Stefanetti V, Coletti M, Timoney PJ, Passamonti F.Herpesviral infections frequently occur in horses. The objective of this study was to investigate the possible association of equine herpesviruses (EHV-1, EHV-2, EHV-3, EHV-4, EHV-5) with other causes of abortion, neonatal mortality or placental disorder. Sixty-seven abortions, 22 stillbirths, 14 cases of neonatal foal mortality and 3 cases of placental disease were investigated for infectious and non-infectious causes. Type-specific nested PCR assays and virus isolation were performed to detect EHV infections. A cause of fetal loss or placental disease was reached in 68 out 116 (58.7%) cases....
Leroux AA, Detilleux J, Sandersen CF, Borde L, Houben RM, Al Haidar A, Art T, Amory H.Risk factors for cardiac diseases in horses have not been explored in a large population of animals. Objective: To describe risk factors for various cardiac diseases in a hospital-based population of horses. Methods: Files of 3,434 horses admitted at the Internal Medicine Department of the Liege Equine Teaching Hospital between 1994 and 2011 were reviewed and of those, 284 were categorized as having moderate-to-severe cardiac disease. Methods: Observational study. After calculating prevalence for each cardiac disease, we tested whether breed (chi-square test) or sex, age, body weight (BW), and...
Silva JR, Medeiros LC, Reis VP, Chavez JH, Munhoz TD, Borges GP, Soares OA, Campos CH, Machado RZ, Baldani CD, Silva ML, Faria JL, Silva EE....Since the emergence of West Nile virus (WNV) in North America in 1999, there have been several reports of WNV activity in Central and South American countries. To detect WNV in Brazil, we performed a serological survey of horses from different regions of Brazil using recombinant peptides from domain III of WNV. Positive samples were validated with the neutralisation test. Our results showed that of 79 ELISA-positive horses, nine expressed WNV-specific neutralising antibodies. Eight of the infected horses were from the state of Mato Grosso do Sul and one was from the state of Paraíba. Our resu...
Caffara M, Piva S, Pallaver F, Iacono E, Galuppi R.Fourteen Cryptosporidium isolates from hospitalized foals were genotyped and subtyped using PCR-RFLP analysis of the 18S rDNA. Cryptosporidium parvum and Cryptosporidium horse genotype were detected in 3 and 11 stool specimens, respectively. Sequences of the gp60 gene of Cryptosporidium horse genotype allowed identification of the subtype family VIaA15G4, defining a novel microsatellite pattern within horse subtype VIa. Cryptosporidium horse genotype has only been described occasionally worldwide and this is the first time it has been identified in foals from Italy.
Wong D, Hepworth K, Yaeger M, Miles K, Wilgenbusch C.An 8-year-old Thoroughbred mare presented for decreased appetite, ataxia, and weakness. Abdominal ultrasound revealed a large volume of anechoic fluid along with multiple masses involving the spleen, liver, and diaphragm. Pleural fluid was identified via ultrasonography and thoracic radiography. Thoracic radiographs also identified pulmonary interstitial nodules, an undulant dorsal diaphragmatic margin and enlargement of tracheobronchial lymph nodes. Clinical signs of weakness and mild seizures were concurrent with hypoglycemic episodes. The final diagnosis was cholangiocarcinoma with extensiv...
Hemberg E, Einarsson S, Jones B, Mikko S.The objective of this study was to investigate the presence and origin of polymorphonuclear leucocytes (PMNLs) in the amniotic fluid of mares giving birth to healthy foals. Material from 25 mares was included. Amniotic fluid was collected during parturition before breakage of the amniotic vesicle. Manual microscopic cytologic evaluation was made on cytospin preparations after staining. PMNLs were found in all amniotic samples examined. The genomic DNA was extracted from 12 of the amniotic fluid samples and was genotyped. The results indicate that the PMNLs originate from the foetus.
Whitton RC, Jackson MA, Campbell AJ, Anderson GA, Parkin TD, Morton JM, Boden LA.A retrospective cohort study was performed to compare the rates of musculoskeletal injury (MSI) in horses receiving local corticosteroid injection (LCI) with those that were untreated and those prior to treatment. Of the 1911 study horses, 392 had been treated. A LCI was defined as any injection of corticosteroid into or adjacent to a synovial structure, muscle, or tendon/ligament. A MSI was defined as any limb injury identified by a veterinarian, following which the horse did not race for at least 6 months, or was retired. Hazard ratios (HR) comparing hazard of injury following injection to t...
Theelen MJ, Wilson WD, Edman JM, Magdesian KG, Kass PH.Sepsis is an important cause of death in foals. Knowledge of which pathogens are likely to be involved is important for selection of antimicrobial drugs for initial treatment. Objective: To identify temporal trends in prevalence of bacteria isolated from foals with sepsis between 1979 and 2010. Methods: Retrospective review of medical records. Methods: All foals ≤30 days of age presented to the Veterinary Medical Teaching Hospital (VMTH) at the University of California, Davis between 1979 and 2010, with a diagnosis of sepsis confirmed by culture of bacteria from blood or internal organs (ant...
Theelen MJ, Wilson WD, Edman JM, Magdesian KG, Kass PH.Monitoring the development of antimicrobial resistance is important for the rational selection of appropriate antimicrobial drugs to initiate treatment of foals with sepsis. Objective: To identify temporal trends in antimicrobial susceptibility patterns of bacteria isolated from foals with sepsis. Methods: Retrospective review of medical records. Methods: Foals aged <30 days with a diagnosis of sepsis, confirmed by culture of bacteria, were included. Susceptibility data, expressed as minimum inhibitory concentrations (MICs) (MIC50 , MIC90 , MIC range) and percent of isolates that were suscepti...
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...
Calzolari M, Monaco F, Montarsi F, Bonilauri P, Ravagnan S, Bellini R, Cattoli G, Cordioli P, Cazzin S, Pinoni C, Marini V, Natalini S, Goffredo M....West Nile virus (WNV) is one of the most serious public health threats that Europe and the Mediterranean countries are currently facing. In Italy, WNV emerged in 1998 and has been circulating since 2008. To tackle its continuous incursions, Italian national and regional institutions set up a surveillance program, which includes the serological screening of sentinel horses, sentinel-chickens and backyard poultry flocks and the surveillance on all equine neurological cases, resident captured and wild dead birds, and vectors. This communication aims to assess the importance of the entomological s...
da Piedade I, Skive B, Christensen H, Bojesen AM.We present the draft genome sequence of Streptococcus equi subsp. zooepidemicus S31A1, a strain isolated from equine infectious endometritis in Denmark. Comparative analyses of this genome were done with four published reference genomes: S. zooepidemicus strains MGCS10565, ATCC 35246, and H70 and S. equi subsp. equi strain 4047.
Canisso IF, Pinn TL, Gerdin JA, Ollivett TL, Buckles EL, Schweizer CM, Ainsworth DM.A 5-year-old Quarter horse broodmare was evaluated for inappetence, depression, and diarrhea 13 days after aborting a 9-month gestation fetus. Clinical and laboratory examination ruled out uterine rupture and peritonitis. Ultrasonography of the uterus combined with cytological analysis of peritoneal fluid suggested the existence of diffuse lymphoma. A multicentric B-cell lymphoma involving the uterus and ovary was confirmed at necropsy and histopathological examination. Lymhome multicentrique à cellules B comme cause possible d’avortement chez une jument poulinière Quarter Horse. Une jumen...
Voynick BT, Sweeney CR.Philippine polo and racing horses were examined for exercise-induced pulmonary hemorrhage after their competitive exercise. Exercise-induced pulmonary hemorrhage occurred in 11.1% of the polo horses and 64% of the racing horses. None of the horses had blood at the nostrils.
Chiewsilp D, McCown JM.Repeated clot formation in mouse ascitic fluids containing antiviral antibody was eliminated by acid precipitation of the fibrinogen.
Wysocka B, Kluciński W.The aim of the present study was to use endoscopic evaluation to compare the grade of accumulation of discharge in the lower airways of horses with recurrent airway obstruction (RAO) and inflammatory airway disease (IAD), and to estimate the usefulness of endoscopic evaluation in differential diagnosis of these diseases. Endoscopic evaluation consists of: the amount of discharge in the lower part of the trachea and tracheal bifurcation, and the assessment of tracheal septum thickness. This study was performed on 248 horses, 10 were healthy, 97 were diagnosed as RAO, and 141 were diagnosed as I...
Cole DJ, Snowden K, Cohen ND, Smith R.Feces collected from three asymptomatic horses and seeded with Cryptosporidium parvum oocysts (10(1) to 10(6)/g of feces) were evaluated by acid-fast staining (AF), an immunofluorescent antibody (IFA) technique, and flow cytometry. The thresholds of detection were 5 x 10(5) oocysts/g of feces for the IFA and AF techniques and 5 x 10(4) oocysts/g for flow cytometry.
Traub-Dargatz JL, Dargatz DA, Morley PS, Dunowska M.Infection control entails preventing or minimizing exposure to infectious agents or optimizing resistance to infection at the individual and population levels should exposure occur. The degree to which each of these strategies is applied varies according to the attributes of the disease agent and the population at risk. In developing an infection control, biosecurity, or biocontainment plan, it is important to decide which agent or agents are to be controlled, the method by which they might be introduced to the individual or population, and methods by which they might spread once at a farm or ...
Arseneau AM, Hrabak TM, Waibel KH.A wealth of literature exists regarding common allergies to household pets such as cat or dog. Allergy to horse, however, is infrequently discussed in the medical literature despite significant sensitization rates among urban-dwelling subjects without direct exposure to horses. A literature search was conducted in PubMed and additional references were collected from surveying the references of the pulled articles. This review summarizes aspects of IgE-mediated horse allergy including the prevalence and mechanisms for sensitization, clinical presentation, molecular characterization of the major...
Burrows GE.Endotoxins are non-protein fragments of the cell wall of Gram-negative bacteria. They must be absorbed into the circulation to produce disease and systemic effects are similar, regardless of bacterial source. Absorption of endotoxins occurs in obstructive bowel disease and may play a significant part in determining the severity of the disease. Many of the responses to experimentally administered endotoxin are identical to those of bowel diseases or the horse and include circulatory, haematological and metabolic alterations. Therapeutic approaches are indirect and include many drugs currently e...
Lees MJ, Kleider N, Tuddenham TJ.Five horses were presented because of a dermatitis of the forehead. Unlike previous reports, ventral midline dermatitis was not the major problem, and was present in only two of five cases. All five horses responded to levamisole therapy at a daily dosage of 5.5 g for one week. Owners were cautioned that repeat therapy may be necessary.
Zhang L, Lei Y, Liu X, Wang X, Liu Z, Li D, Zheng P, Zhang L, Chen S, Xie P.Borna disease virus (BDV) is a neurotropic, enveloped, non-segmented, negative-stranded RNA virus that infects a wide variety of vertebrate species from birds to humans across a broad global geographic distribution. Animal symptomatology range from asymptomatic infection to behavioral abnormalities to acute meningoencephalitis. Asymptomatic BDV infection has been shown to be more frequent than conventionally estimated. However, the molecular mechanism(s) underyling asymptomatic BDV infection remain largely unknown. Here, based on real-time quantitative PCR and Western blotting, a total of 18 h...
McCrory P, Turner M, Murray J.The case is reported of a retired professional jockey with progressive memory loss. The concern is that he may be suffering from chronic traumatic encephalopathy or the "punch drunk syndrome".
Orzan F, Angelini P, Oglietti J, Leachman RD, Cooley DA.Two cases of horseshoe lung are described; one was suspected and the other was diagnosed preoperatively. Both underwent successful surgical treatment. The embryology of this anomaly is briefly reviewed with reference to the closely related scimitar syndrome (anomalous venous return of right lung to inferior atriocaval junction). Diagnostic studies are discussed with stress on the need for a thorough functional evaluation of both the heart and lungs before the surgical indication is made.
McGuire TC, Poppie MJ, Banks KL.Measurement of serum immunoglobulins in 46 foals less than 2 weeks old revealed 9 foals with hypogammaglobulinemia. The hypogammaglobulinemia was attributed to failure in transfer of immunoglobulins from dam to foal via colostrum. Three of the affected foals did not nurse at all, or only slightly, and 2 of these died of infections within a few days after birth, whereas the 3rd foal did not grow as well as normal foals. Six of the affected foals nursed in an apparently normal manner, and 5 of these had nonfatal respiratory infections between 2 and 5 weeks of age. Analysis of serum samples from ...
Watts AE, Fubini SL, Vernier-Singer M, Golkowski C, Shin S, Todhunter RJ.To determine the effect of nonthermal plasma on Staphylococcus aureus, fibroblasts in monolayer culture, and clean and contaminated skin explants. Methods: Normal skin from euthanized horses. Methods: S aureus organisms were plated and treated with nonthermal plasma followed by bacterial culture to assess viability. Fibroblasts in monolayer culture and the epidermal and dermal surfaces of clean and S aureus-contaminated skin explants were treated. The effects of distance and duration on the response to treatment were compared. Results: Compared with controls, treatment with nonthermal plasma r...
Xiao L, Herd RP.Diarrhoea is one of the most important diseases of foals and
7040% are affected within the first 6 months of life (Palmer
1985). Although the cause is multifactorial and changes in the
physiology and nutrition of foals are sometimes responsible,
diarrhoea is frequently the result of infection by enteropathogens
such as bacteria, viruses and nematodes (Palmer 1985; Tzipori
1985). There is increasing evidence that Cryptosporidium
infection can also cause diarrhoea in foals (Austin et a/. 1990;
Kim 1990).
Cryptosporidiosis in horses is caused by Cryptosporidium
parvum, a coccidial paras...
Selim SA, Soliman R, Osman K, Padhye AA, Ajello L.Isolation of Histoplasma farciminosum from five horses, showing typical signs of histoplasmosis farciminosi (epizootic lymphangitis) was successfully attempted. The mycelial form of H. farciminosum was isolated on Sabouraud dextrose agar enriched with 2.5% glycerol, brain heart infusion (BHI) agar enriched with 10% horse blood and PPLO dextrose glycerol agar. The last medium proved to be the most effective, both for primary isolation and subculturing of the fungus. It was found that on primary isolation, the lag phase of the mycelial form of the fungus was relatively long, involving 4-8 weeks ...
McMullan WC, Joyce JR, Hanselka DV, Heitmann JM.Amphotericin B was used systemically or locally, or both, in the treatment of localized subcutaneous phycomycosis in horses. In 8 of 10 cases, the results were satisfactory. Intravenous treatment was well tolerated at an average starting daily dosage of 0.38 mg/kg, increasing up to as high as 1.47 mg/kg. It was concluded that the ideal treatment regimen would include early surgical removal of the lesion followed by daily intravenous and topical administration of amphotericin B, with periodic extirpation of small necrotic tracts as necessary.
Herholz C, Straub R, Braendlin C, Imhof A, Lüthi S, Busato A.Tidal breathing flow-volume loop (TBFVL) indices in healthy horses and in horses suffering from mild and moderate to severe recurrent airway obstruction (RAO) were measured. In addition, the ability of these indices to differentiate healthy controls from horses with mild RAO by separating the horses according to their usage was investigated. The horses were assigned to three sporting categories: 1 Leisure horses; 2 Horses competing at events with a duration of more than five minutes (eventing, coaching and endurance); and 3 Horses competing at events with a duration of less than five minutes (...
Cabasso VJ, Nieman R, Schroeder DD, Hok KA, Louie RE, Mozen MM.A horse has been immunized with Australia antigen (Au/SH) purified 20-fold by a procedure employing gel filtration of Cohn fraction IV derived from an Au/SH-positive human plasma pool. Hyperimmunization was initiated by the intramuscular injection of 20 ml of a mixture of equal parts of purified Au/SH and complete Freund's adjuvant. The 20-ml volume was divided into four 5-ml doses, two of which were administered on each side of the horse's neck. Booster doses of antigen alone were given as follows: 10 ml intravenously 30 days later and 5 ml intramuscularly on each of days 77 and 205. Au/SH an...
Schmidtmann ET, Robl MG, Carroll JF.The capability of field-collected American dog ticks, Dermacentor variabilis, to infect horses with Ehrlichia risticii, causative agent of Potomac horse fever (PHF), was examined by allowing adult ticks collected from horse farms with a history of PHF to feed on susceptible horses. More than 500 male and female ticks attached and fed on 3 test horses; however, no clinical or serologic evidence of PHF was observed in treated or control horses. All horses were challenge exposed with E risticii-infective blood by inoculation at 60 to 65 days after ticks fed, and all developed clinical PHF with su...