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.
Saengseesom W, Kasempimolporn S, Akesowan S, Ouisuwan S, Sitprija V.A therapeutic anti-rabies immunoglobulin for human use has been produced mainly in horses. The presently available seroneutralization test, the rapid fluorescent focus inhibition test (RFFIT), is laborious and rather difficult to carry out in horse farms. This study was undertaken to develop a simple latex agglutination test (LAT) for determining rabies antibodies in horse sera. LAT was validated by testing a total of 468 horse serum samples characterized by RFFIT. Of these, 253 of 260 samples with antibody titers of less than 100 IU/ml had agglutination score of 1+, whereas 174 of 208 samples...
Marshall VL, Secombe C, Nicholls PK.A 6-week-old Warmblood colt foal was presented for investigation of multiple haematoma formation in various locations, poor wound healing and abnormal scar formation. Based on the history and clinical presentation of hyperextensible skin with prolonged skin tenting, the foal was diagnosed with cutaneous asthenia and euthanased because of the poor prognosis. Histopathological and electron microscopic findings were inconclusive. This is the first case report of cutaneous asthenia in a Warmblood horse in Australia. Cutaneous asthenia is reviewed with particular reference to hereditary equine regi...
Hagos A, Degefa G, Yacob H, Fikru R, Alemu T, Feseha G, Claes F, Goddeeris BM.This paper presents the results of a seroepidemiological survey of trypanozoon infection in horses carried out between September 2007 and June 2008. The survey was conducted to determine the seroprevalence of anti-trypanozoon antibodies in 880 serum samples collected randomly from selected horse-breeding districts of the Bale highlands of Ethiopia. The seroprevalence of trypanozoon infection was found to be 173 (19.66%) and 140 (15.91%) for the CATT/T. evansi and LATEX/T. evansi tests, respectively. The high seroprevalence of trypanozoon infection strongly indicates that the infection is endem...
Sünder U, Moors E, Hagemann K, Gauly M.The aim of this study was to estimate the effects of flying insects (Order Diptera) on the behaviour of grazing horses in relation to the use of insecticide and repellent substances. The investigations were done between June and August in 2008 in 3 periods of 7 days each. As insecticide and repellent two substances were used: "Well-care emulsion" (Co. Essex Tierarznei, München, GER) containing Permethrin and "Bremsen-Frei-Plus" (Co. Dr. Schaette AG, Bad Waldsee, GER) based on etheric oils. Both groups were compared with a non treated control group in a crossover-design. Each group (n = 3-5) w...
Aleman M, Williams DC, Jorge NE, Magdesian KG, Brosnan RJ, Feary DJ, Hilton HG, Kozikowski TA, Higgins JK, Madigan JE, Lecouteur RA.Botulism is a potentially fatal paralytic disorder for which definitive diagnosis is difficult. Objective: To determine if repetitive stimulation of the common peroneal nerve will aid in the diagnosis of botulism in foals. Methods: Four control and 3 affected foals. Methods: Validation of the test in healthy foals for its comparison in foals with suspected botulism. Controls were anesthetized and affected foals were sedated to avoid risks of anesthesia. The common peroneal nerve was chosen for its superficial location and easy access. Stimulating electrodes were placed along the common peronea...
Espinoza JR, Terashima A, Herrera-Velit P, Marcos LA.Fasciola hepatica is the causative agent of fasciolosis in Peru; the disease is an important public health problem by the high prevalence of the human infection affecting mainly children and a major veterinary problem by the high rates of infected livestock. The human disease is endemic in the Sierra and the Coast but sporadic in the Amazonia, and reported in 18 Departments, while the animal infection in 21 of 24 Departments of Peru. Transmission occurs in Andean rural populations engaged in agriculture, but recently an increasing number of people became infected in the cities. The epidemiolog...
Bründler P, Frey CF, Gottstein B, Nussbaumer P, Neuhaus S, Gerber V.An association between equine recurrent airway obstruction (RAO) and increased resistance to intestinal parasites has been demonstrated in descendants of an RAO-affected stallion. It was hypothesised that members of another high-incidence RAO family (F) and unrelated RAO-affected Warmblood horses (UA) would shed fewer strongylid eggs than unrelated RAO-unaffected pasture mates (PM) under the same environmental conditions. Faecal worm egg counts were performed on faecal samples (63 F, 86 UA, 149 PM) and classified into three categories: 0, 1-100 and >100 eggs per gram. While results for F di...
Kokotovic B, Angen Ø, Bisgaard M.Genetic diversity detected by analysis of amplified fragment length polymorphisms (AFLPs) of 54 Actinobacillus lignieresii isolates from different hosts and geographic localities is described. On the basis of variances in AFLP profiles, the strains were grouped in two major clusters; one comprising strains isolated from horses and infected wounds of humans bitten by horses and another consisting of strains isolated from bovine and ovine hosts. The present data indicate a comparatively higher degree of genetic diversity among strains isolated from equine hosts and confirm the existence of a sep...
Yamamoto H, Yamamoto F, Tanaka F, Nishikawa Y.We describe the influence of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia on histopathological alteration of a glutaraldehyde-fixed equine pericardial roll (EPR) graft in a 77-year-old male who underwent in-situ EPR replacement of a ruptured infected abdominal aorta with concomitant repair of the perforated duodenum. The patient died of circulatory failure after septic shock due to MRSA infection and gastrointestinal bleeding on postoperative day (POD) 23. The autopsy revealed no perforation of the EPR graft or anastomotic disruption between the native abdominal aorta and EPR ...
Wilkins PA.Rapid evaluation and intervention is a requirement and a characteristic of patient management in neonatal intensive care units, and this applies for equine neonates also. Appropriate interventions are based on solid knowledge of age, maturity, and species-specific differences in reference ranges. Point-of-care (POC) testing devices speedup decision making regarding treatments and interventions. However, there are potential limitations of these devices when applied to age groups and species beyond those they were specifically developed for. This article discusses the age-specific differences in...
Singh BR, Gulati BR, Virmani N, Chauhan M.At a thoroughbred equine breeding farm near Hissar (Haryana), three mares aborted in their seventh month of pregnancy. The vaginal swabs of all aborted mares, and stomach contents, heart blood, liver, spleen and placenta of aborted fetuses yielded pure culture of Aeromonas hydrophila. In addition, A. hydrophila was also isolated from the vaginal swabs of three repeat breeding mares and faecal sample of a diarrheic foal. The source of infection was possibly water supply as all the water samples collected from taps, mother tank and storage tank were found to be positive for A. hydrophila. The an...
Sanz MG, Wills TB, Christopherson P, Hines MT.A 17-year-old Peruvian Paso mare was evaluated for bilateral epistaxis that had been present for at least 3 years. The mare had mild anemia, platelet count within the reference interval, unremarkable coagulation times, and a negative Coggins test. On endoscopic examination, structural abnormalities were not observed in the nasal cavities, pharynx, larynx, trachea, or either guttural pouch, but petechiation was noted in the nasal mucosa. Additional tests revealed prolonged cutaneous bleeding time, normal concentration of von Willebrand factor antigen, an abnormal clot retraction test, and failu...
Romero AE, Rodgerson DH.Diaphragmatic rent and visceral herniation in the horse is seldom diagnosed, but historically carries a poor prognosis. The objective of this study was to document the presentation and surgical management of all diaphragmatic rents as presented to 2 referral institutions over a 5-year period. A review of 31 cases demonstrated that even with advances in surgical management of abdominal and thoracic conditions, little has been done to change the prognosis for this condition. Success rate was 23% for all horses presented for colic and were ultimately diagnosed with a diaphragmatic hernia, and 46%...
Berzina I, Trumble NS, Novicki T, Sharkey LC.An 11-year-old American Saddlebred gelding was presented for evaluation of a nonpainful subconjunctival mass involving the lateral canthus of the left eye. Other findings included a central corneal scar and a small central cataract of the lens in the left eye. Fine-needle aspiration of the mass was performed and cytologic examination revealed marked pyogranulomatous inflammation with intralesional fungal hyphae, consistent with mycetoma. The fungal structures were elongated and characterized by nonstaining walls; several bulbous yeast-like structures were also observed. The mycetoma was surgic...
Rudi K.Mainly due to the lack of time-series data, we know very little about the underlying interactions leading to adverse states in the gut. I therefore investigate the host-bacteria dynamic interactions in a recently published acidotic state induction time-series experiment. Too high levels of fermentation in the hindgut may lead to elevated serum lactate levels, which is a characteristic of the acidotic state. The acidotic state was induced through injection of oligofructose directly into the caecum of five horses, with subsequent temporal measurements of host serum lactate, and a range of caecum...
Hart KA, Barton MH, Ferguson DC, Berghaus R, Slovis NM, Heusner GL, Hurley DJ.Relative cortisol insufficiency occurs in septic foals and impacts survival. Serum free (biologically available) cortisol concentration might be a better indicator of physiologic cortisol status than serum total cortisol concentration in foals. Objective: In septic foals, (1) low free cortisol concentration correlates with disease severity and survival and (2) predicts disease severity and outcome better than total cortisol concentration. Methods: Fifty-one septic foals; 11 healthy foals; 6 healthy horses. Methods: In this prospective clinical study, foals meeting criteria for sepsis at admiss...
Hébert L, Moumen B, Duquesne F, Breuil MF, Laugier C, Batto JM, Renault P, Petry S.Taylorella equigenitalis is the causative agent of contagious equine metritis (CEM), a sexually transmitted infection of horses. We herein report the genome sequence of T. equigenitalis strain MCE9, isolated in 2005 from the urethral fossa of a 4-year-old stallion in France.
Meyer A, Messer L, De Briel D, Moreau P.The field of zoonoses changes constantly. Streptococcus equi subsp. ruminatorum is a group C Streptococcus subspecies first identified in 2004. The first case of human infection with this agent was reported in 2007. Here, we report a second case. A 70-year-old man had acute spondylodiscitis and endocarditis involving the anterior mitral valve leaflet. S. equi subsp. ruminatorum was identified in the blood cultures. Antibiotic therapy was successful in eradicating the infection. The workup showed hypogammaglobulinemia with stage I myeloma. He reported frequent contacts with horses including tw...
Castleman WL, Toplon DE, Clark CK, Heskett TW, Farina LL, Lynch TM, Bryant UK, Del Piero F, Murphy B, Edwards JF.This multi-institutional report describes 8 cases of rhabdomyosarcoma in horses. Four neoplasms were in the tongue and other areas of the mouth or head, 2 were in the abdominal wall, and 1 each was in right shoulder muscles and heart. Four rhabdomyosarcomas that were less than 10 cm in diameter were treated by surgical excision or radiation with no recurrence. Two neoplasms greater than 10 cm in diameter in the abdominal wall and the right shoulder were considered inoperable and led to decisions to euthanize the horses. Two neoplasms were incidental findings at necropsy. All the neoplasms were...
Schwarz BC, van den Hoven R, Schwendenwein I.The myeloperoxidase index (MPXI) was investigated as a diagnostic indicator of systemic inflammation in a retrospective study using data from 859 hospitalised horses. A reference interval of 8.5-10.4 for the MPXI was established. In horses with systemic inflammatory response syndrome (SIRS), the MPXI was significantly lower than in healthy horses, those with localised inflammation and those with sepsis. The MPXI in horses with sepsis was also significantly lower than in healthy animals and those with localised inflammation. Horses in the SIRS group with leucopenia, white blood cell (WBC) count...
Kitai Y, Shirafuji H, Kanehira K, Kamio T, Kondo T, Konishi E.West Nile virus (WNV) and Japanese encephalitis (JE) virus are distributed separately in the world with some exceptions. There is a concern that WNV may invade into Asia where JE virus exists. On and after such invasion, any differential diagnosis could be complicated by serological crossreactivities. We previously demonstrated experimentally using horses infected with WNV that preimmunization with inactivated JE vaccine considerably affected the ability of neutralization tests and immunoglobulin M (IgM) antibody-capture enzyme-linked immunosorbent assay (ELISA) to diagnose WNV infection. Here...
Hijazin M, Ulbegi-Mohyla H, Alber J, Lämmler C, Hassan AA, Prenger-Berninghoff E, Weiss R, Zschöck M.An Arcanobacterium haemolyticum strain isolated from a postcastrational lesion of a horse was identified phenotypically and genotypically. The latter was performed by sequencing the 16S-23S rDNA intergenic spacer region (ISR), by amplification of the gene encoding A. haemolyticum phospholipase D, by amplification of A. haemolyticum specific parts of ISR-23S rDNA and by amplification of the newly described CAMP factor family protein encoding gene of A. haemolyticum. This indicates (as described previously for seven additional A. haemolyticum strains; Hassan et al. 2009) that A. haemolyticum see...
Baker JR, Ellis CE.The causes of death recorded in 480 consecutive post mortem examinations of horses performed at the department of pathology, Veterinary Field Station, University of Liverpool, between February 1958 and February 1980, are reported. The alimentary, locomotor and nervous systems were those most frequently diseased. The most common specific entities were those associated with grass sickness, fractures and endoparasitism.
Meyer JC, Hunyadi LM, Ordóñez-Mena JM.Accuracy of baseline ACTH for the diagnosis of PPID in horses varies between studies. Objective: To estimate the diagnostic accuracy of ACTH as a biomarker for PPID in adult horses and appraise potential causes of heterogeneity. Methods: Systematic review and meta-analysis. Methods: A literature review identified studies reporting diagnostic accuracy data for extraction. Risk of bias was evaluated using QUADAS-2. Two random-effects models, the hierarchical summary receiver operating curve (HSROC) and the bivariate binomial normal model (BBN) were used to pool accuracy measurements. We performe...
Davis AM, Fan X, Shen L, Robinson P, Riggs CM.Palmar osteochondral disease (POD) is common in the Thoroughbred racehorse yet difficult to diagnose by radiography alone. Objective: To improve the sensitivity and specificity for diagnosing POD from radiographs. Methods: Prospective, longitudinal study. Methods: Radiographs in nine different projections were made of metacarpophalangeal joints (MCPJ) of 50 Thoroughbreds. Post-mortem, MCPJs were dissected and gross pathology was scored. Three experienced Thoroughbred clinicians read each radiograph and recorded their findings. Another clinician reviewed each radiograph alongside the related gr...
Hunter DJ, Macmaster R, Roszak AW, Riboldi-Tunnicliffe A, Griffiths IR, Freer AA.Equine P2 protein has been isolated from horse spinal cord and its structure determined to 2.1 A. Since equine myelin is a viable alternative to bovine tissue for large-scale preparations, characterization of the proteins from equine spinal cord myelin has been initiated. There is an unusually high amount of P2 protein in equine CNS myelin compared with other species. The structure was determined by molecular replacement and subsequently refined to an R value of 0.187 (Rfree=0.233). The structure contains a molecule of the detergent LDAO and HEPES buffer in the binding cavity and is otherwise ...
Berryhill EH, Magdesian KG, Tadros EM, Edman JE.Maintaining serum glucose concentrations is critical in neonatal foals and is often dysregulated in illness; however, few studies have assessed the effects of age, or variation of glucose and insulin, in neonates and their postpartum dams. This study aimed to serially evaluate serum glucose and insulin concentrations and glucose/insulin (G/I) ratios in seven healthy foals and their dams immediately postpartum and at 1-2 and 10-12days of age. The hypotheses were that: (1) there would be wide temporal variation in hourly glucose and insulin measurements among foals; and (2) measured parameters i...
Senior M.To review information on the pathogenesis, diagnosis and treatment of post-anaesthetic pulmonary oedema in horses. Methods: Pubmed 1970-present, personal files.
Steinbach TJ, Reischauer A, Kunkemöller I, Mense MG.A neonatal foal was presented with a 6.5-cm pedunculated mass arising from the upper deciduous incisors. The distal end was soft and covered by haired skin, whereas the proximal end was firm, covered with mucosal epithelium, and at the point of transection contained a fully developed tooth. Microscopically, the mass was covered by epidermis and mucosal epithelium and the remaining portion of the mass consisted of mature collagen, nonneoplastic fat and smooth muscle, and a single tooth within a bony socket. The mass is consistent with an oral choristoma and has features similar to those describ...
Klei TR, Torbert BJ, Chapman MR, Ochoa R.Nonimmune pony foals 9 to 12 mo of age were vaccinated with third-stage Strongylus vulgaris larvae (L3) irradiated with 70, 100, or 130 Kr of gamma radiation. Ponies receiving per os inoculations of L3 irradiated with 70 or 100 Kr were protected from the clinical disease and lesions associated with challenge infections of 4,300 L3, when compared to nonvaccinated controls. Similarly, the numbers of worms from the challenging population recovered from successfully vaccinated animals were significantly lower than from nonvaccinated controls. The degree of resistance that develops in individuals c...
Morris DD, Beech J.Disseminated intravascular coagulation (DIC) was diagnosed as a secondary disease in 6 horses. Four horses had localized and/or systemic sepsis, one horse had disseminated neoplasia, and one had idiopathic ulcerative enteropathy. The diagnosis of DIC was based on the finding of at least 3 of 4 abnormalities: thrombocytopenia, prolonged prothrombin time, prolonged activated partial thromboplastin time, and a high concentration of fibrinolytic degradation products. The most common clinical signs other than those attributable to the primary disease process were abnormal hemorrhage (4 hours) and v...
Gorji FF, Sadr S, Borji H.Eimeria is a genus of protozoan parasites that infect many animal species, including horses. We conducted a cross-sectional study of indigenous breeds of horses from the North and Northeast of Iran to establish the prevalence and distribution of Eimeria species. Methods: Using standard coprological techniques, 340 faecal samples from randomly selected horses (141 from North Iran and 199 from Northeast Iran) were examined for Eimeria oocyst. Results: Out of 340 samples, only three from north Iran were positive for coccidiosis. Infections occurred by Eimeria leuckarti. The mean intensity of oocy...
Weller R, Cauvin ER, Bowen IM, May SA.Diagnosis of temporomandibular joint disease in the horse presents a challenge to the equine veterinarian. This case report illustrates a combined imaging approach using radiography, scintigraphy and ultrasonography in a horse with severe arthropathy of the left temporomandibular joint. Radiographs were inconclusive. Scintigraphy with Tc99m methylenediphosphonate localised, but failed to characterise the disease process; ultrasonography was the only imaging method which both localised and characterised the lesion. Ultrasonography proved to be a relatively cheap, technically easy to perform and...
Carr EA, Holcombe SJ.Nutritional supplementation is becoming the standard of practice in equine medicine, although there are minimal data on nutritional support in critically ill horses and its association or effect on morbidity and mortality or length of hospital stay. Horses can be fed orally and when that is not possible, intravenously or parenterally. Enteral feeding is less expensive, more physiologic, improves immunity, and is easier and safer. This article reviews available information on the development of a nutritional plan for critically ill horses, and describes methods for and complications of enteral ...
Heymering HW.For most of history, the causes of laminitis have been based on observations. In the last 30 years or so, however, the number of theories has exploded, with only a few being confirmed by experiments. This article highlights these theories.
Waller A., head of bacteriology at the AHT, describes the causative agent of strangles in horses, and discusses progress with the latest research aimed at improving vaccines against this global disease.
Donnelly J, Joyner LP, Frank C.Racehorses imported into Kuwait were tested for serum antibodies to Babesia equi and B. caballi by complement fixation (CF) and indirect fluorescent antibody (IFA) tests. The prevalence of B. equi was high (77.1% by IFA) whereas that of B. caballi was much lower (11.4%). Data for B. equi showed that infection was acquired after about 6 months at risk and that in the following 12 months animals had antibody levels detectable by both CF and IFA tests by 24 months the CF reaction was no longer detectable. Estimates of incidence and inoculation rates were calculated and found to be consistent with...
Nakazawa M, Sugimoto C, Isayama Y.The selective isolation of R. equi in NANC medium was made by quantitative culture of the organism in the feces. R. equi was observed in the feces of all the mares and foals investigated. The mean viable count of R. equi organisms in 1 gram of feces was 8.42 X 10(2) in the mares and 7.57 X 10(2) in the foals, and its 95% confidence limits were in a range of 6.48 X 10(2) to 1.09 X 10(3) and 4.19 X 10(2) to 1.37 X 10(3), respectively. This result indicates that R. equi is a member of the normal intestinal flora in the horse.
Murray RC, Dyson SJ, Schramme MC, Branch M, Woods S.Chronic laminitis is a severe disease affecting the equine digit. It was hypothesized that magnetic resonance (MR) imaging would improve visualization of structures within the foot and pathology associated with chronic laminitis. This study aimed to describe the MR imaging findings in chronic laminitis, compare different pulse sequences for visualization of pathology, and to compare MR imaging with standard radiography. Twenty (10 forelimb, 10 hindlimb) cadaver limbs from 10 horses clinically diagnosed with chronic laminitis (group L) and 10 limbs without laminitis (group N) were used. Laterom...
Peeters LM, Janssens S, Brebels M, Buys N.Genetic factors involved in susceptibility to insect bite hypersensitivity (IBH) in Belgian Warmblood horses (BWP) were investigated. Data relating to 3409 horses were collected using a questionnaire, administered to owners during sport competitions, BWP breeding days, breeder visits and after phone calls. Horses were classified as IBH-affected or unaffected, based on two 'disease classifiers': a lifetime record, based on owner information (life_status) and another based on whether or not the horse was showing clinical signs at the time of questioning (clin_status). IBH prevalence was 10% base...