Disease etiology in horses refers to the study of the causes and development of diseases within equine populations. It encompasses various factors, including genetic predisposition, environmental influences, infectious agents, and nutritional imbalances, that contribute to the onset and progression of diseases in horses. Understanding disease etiology is essential for identifying risk factors and implementing preventative measures in equine health management. This topic includes research on pathogen-host interactions, the impact of management practices on disease incidence, and the role of genetic and environmental factors in disease susceptibility. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, contributing factors, and implications of disease etiology in horses.
Grøndahl AM, Jansen JH, Teige J.Fifty-six tarsocrural joints and 94 metatarsophalangeal joints were examined, at necropsy, from horses aged < or = 2 years. Osteochondral fragments at the cranial aspect of the intermediate ridge of the distal part of the tibia were seen in six horses, and at the proximoplantar aspect of the proximal phalanx in seven horses. Defects in the proximoplantar aspect of the proximal phalanx without osteochondral fragments were seen in a further two horses. Inflammatory and degenerative changes were not observed in any of the joints examined. From the incidence and natural course of these fragment...
Diaw OT, Bayssade-Dufour C, Pino De Morales LA, Albaret JL, Vassiliades G.Cercarial chaetotaxy of Gastrodiscus aegyptiacus (Paramphistomoidea), parasite of the Horse, is described. Cercariae were shed by experimentally infected Bulinus forskalii. This description is the first one of a Gastrodiscidae. The cercarial chaetotaxy of the Gastrodiscidae is quite different from those of Paramphistomoidea and Diplodiscidae.
Baum B, Hewicker-Trautwein M, Wohlsein P.A 10-year-old Knabstrupper stallion was euthanatized because of severe dyspnea and exercise intolerance. Postmortem examination revealed diffuse severe alveolar emphysema and chronic fibrosing pleuritis of the caudal lung. Parts of both caudal lung lobes were covered with multiple raised firm gray to yellow plaques. Histologically, these areas consisted of circumscribed pleural fibroses and cysts of metaplastic keratinizing squamous epithelium. Immunohistochemistry revealed intense labeling for cytokeratins 5/6 and 10. In addition, caudal lung lobes were severely affected by a chronic partiall...
Gaskin JM, Neal FC, Rubin HL.Precipitin lines not associated with equine infectious anemia (EIA) were observed in routine agar gel immunodiffusion (AGID) testing for the infection. The serums which produced these lines were obtained from horses which had been given multiple vaccinations with commercially available cell culture-origin equine virus vaccines as part of a comprehensive herd health program. The lines formed against cell culture-derived, but not spleen-derived EIA viral antigens. Investigation revealed that bovine serum proteins in the vaccines induced precipitating antibodies which reacted with bovine serum pr...
Kawahisa-Piquini G, Bass L, Pezzanite LM, Moorman VJ.The role of hoof morphology is increasingly recognized as a factor associated with lameness incidence in performance horses. The primary objective was to evaluate effect of training initiation on hoof unevenness in Quarter Horses (n = 42; 29 2-year-olds, 13 3-year-olds) over 6-months (m) in training (m0, m2, m4, and m6). Horses were objectively assessed for lameness (inertial sensor system) and photographs and radiographs of feet were taken. Hoof measurements were taken (palmar/plantar angles, frog base width/length, toe length/angle, heel length/angle, heel/foot width, wall height/angle), a...
Rosenfeld G, Reichmann CE, Jaria LJ, Andrade SO.Hematological studies were developed on two mares and twelve adults castrate sheeps of "Ideal" breed. The animals had been on a pasture formed with Brachiaria radicans Napper for one and two months respectively. This experiment was developed in winter time, so the leaves of the graminea had a yellow-green color. Clinical and hematological observations were made weekly. The typical symptoms of intoxication failed to present as observed in the former investigation when the plant was green (3). The hematological exames showed only for ovines a slight anemia, it was also characterized as being mac...
Wolf P, Kamphues J.Nutritional disorders in domestic or pet animals depend not seldom on special situations, for example when different influences coincide concerning keeping, housing and offering of feed or water. These lead suddenly to high-risk situations, that can cause sometimes the death of the animal. The following case report deals with two ponies, that were kept on a so-called "petting zoo" and showed repeatedly colic symptoms (always after a weekend). During surgery in the stomach light yellow balls were found, that can be explained by ingestion of 1.0 to 1.5 kg wheat. This cereals consist--depending o...
Costa LR, Santos IK, Issel CJ, Montelaro RC.Cardinal features of equine infectious anemia (EIA) include fever, hemolytic anemia and thrombocytopenia during the acute phase of the disease, and cachexia and anemia seen during the chronic phase. These signs are thought to result from the release of inflammatory cytokines such as TNF-alpha. In order to determine if TNF-alpha has a role in the pathogenesis of acute EIA and vaccine-induced disease enhancement, we measured plasma concentrations of TNF-alpha in ponies immunized with virus enriched major core protein-p26 and/or experimentally infected with EIAV. Naturally infected inapparent EIA...
Hamada M, Itakura C.The morphology of hypomelanosis occurring in experimentally induced equine papillomas was investigated. Histologically, dopa-positive functioning melanocytes were decreased in number from the basal layer in the epidermis. Electron-microscopically, melanogenic organelles in the melanocytes were degenerate and melanosomes were decreased in number and size. In addition, the melanocytes had some abnormal melanosomes including melanosome complexes and giant melanosomes. Some abnormal melanosomes were also present in the keratinocytes. The hypomelanosis seemed to be related to a disturbance in melan...
Barton AK, Kershaw O, Gruber AD, Gehlen H.Recently, a syndrome called "equine idiopathic hemorrhagic cystitis" was described and clinical features compared with bladder neoplasia. In this case report, we describe a case of hemorrhagic cystitis with a favorable outcome in a high-performance dressage horse, in which exercise intensity might be the etiologic factor for the development of bladder-wall hyperplasia and hematuria. A 14-year-old Warmblood gelding was presented with a history of hematuria of 2-day duration. The high-level dressage horse had performed on the previous 3 weekends and was trained at least three times a week at per...
Pemberton AD, John HA, Ricketts SW, Rossdale PD, Scott AM.Failure to inhibit proteinases can lead to excessive tissue damage. The possibility that the severity of endometritis in Thoroughbred mares correlates with the haplotypes of plasma alpha 1-proteinase inhibitor (alpha 1-PI) expressed was investigated in two groups of mares. In mares with pyometritis before treatment, the frequency of the N haplotype, which is already high in the Thoroughbred population, was significantly increased when compared with that in a large published population. In mares with acute endometritis which persisted after treatment followed by sexual rest, the absence of S an...
Thein P, Essich G.An investigation was carried out upon occurrence and course of infectious and non infectious diseases as well as the mortality in foals born and raised at the State Stud Marbach/Lauter between 1982 and 1991. The foals have been investigated from birth to weaning, they consisted of 177 Thoroughbred Arabians and 285 German Warmblood foals (total 462 foals). The diseases were divided into pre-, peri- and postnatal according to their known or assumed cause and onset. There was a preponderance of prenatal diseases (11.25%) whereas the perinatal rate was 1.30% and the postnatal rate of diseases was ...
Akbari Shahkhosravi N, Kakavand R, Davies HMS, Komeili A.The health and performance of horses are significantly affected by diseases associated with the hoof. Laminitis is a critical hoof disease that causes pain and, potentially, severe hoof and bone pathology. Objective: To generate an equine hoof finite element (FE) model to investigate the impact of normal and toe-in hoof conformations on the degeneration (decrease in elastic modulus) of the laminar junction (LJ), as occurs in chronic laminitis. Methods: Computer software modelling. Methods: A hoof FE model was generated to investigate the biomechanics of hoof laminitis. A 3D model, consisting o...
Clyne MJ.Proteoglycan degradation is central to the development of degenerative joint disease. Proteoglycans may be degraded by lysosomal enzymes from chondrocytes, synoviocytes or leucocytes. Collagen and matrix degradation occurs either by direct damage or due to degrading enzymes released into synovial fluid. Once the pathological sequence has begun it continues in a cyclic manner unless arrested by the ability of chondrocytes to synthesise sufficient matrix components. Treatment should ideally be directed to this end.
Milne EM, Pogson DM, Else RW, Rowland AC.One case of caecocaecal intussusception (case 1) and one case of caecocolic intussusception (case 2) in ponies are described. Case 1 showed mild abdominal discomfort for seven days followed by sudden death whereas case 2 showed continuous moderate pain for three weeks. At post mortem examination, case 1 showed intussusception of the base of the caecum into the body whereas in case 2, the entire caecum had invaginated into the right ventral colon. Histopathological examination showed that the lesions in both animals had been present for a long time.
Al-Dissi A.A wide variety of toxins cause diseases in the horse and are investigated routinely by veterinarians and veterinary pathologists to identify the cause of illness and death. A complete investigation involves performing a thorough necropsy and requires macroscopic and microscopic examination of lesions and a variety of laboratory testing to obtain an accurate diagnosis. The identification of gross lesions by equine practitioners is often the first step in formulating a diagnostic plan. This article provides a description of selected common toxins producing detectable gross lesions in horses in N...
Monzon CM, Jara GA, Hoyos CB.The usefulness of the direct agglutination test (DA) to diagnose Mal de Caderas disease was evaluated. Forty four sera samples from two lots of horses with natural T. evansi infection (Lot 1 and Lot 2) were used. Thirteen (81.2%) of sixteen horses in which parasites were isolated gave positive agglutination titres (> or = 1:512) in the DA test. Treatment of these positive sera with 2-mercaptoethanol drops three to eight dilutions the agglutination titres in twelve samples (92%), showing the IgM nature of these antibodies. The DA test was also positive in seventeen of twenty eight horses in ...
Poulsen L, Henriksson FV, Dahl M, Honoré ML, Olsen SN, Leifsson PS, Staerk-Østergaard J, Jacobsen S, Pihl TH.Horses with non-strangulating intestinal infarction (NSII) are often misdiagnosed with idiopathic peritonitis or acute colitis. Early diagnosis is essential to ensure early surgical intervention and improve survival. Clinical and laboratory data from horses admitted to the University of Copenhagen Large Animal Teaching Hospital with NSII, idiopathic peritonitis or acute colitis between 2009 and 2018 were used for univariate comparisons and a multivariable logistic regression model for prediction of NSII. Two hundred and thirty-one horses were included. A multivariable model for the prediction ...
Milne EM, Pemberton AD, McGorum BC, Dixon PM, Miller HR.The equine alpha-1 proteinase inhibitor (alpha 1PI) system differs from that of man in that the equine system consists of four closely-linked genes (Spi1-Spi4) whereas in man, a single gene encodes for alpha 1PI. We have previously found differences in the proportion of the Spi proteins in equine serum and bronchoalveolar lavage fluid (BALF). We therefore wished to determine whether, as reported in man, there was any molecular weight difference between the Spi proteins in serum and BALF. alpha 1PI and albumin from equine BALF migrated further towards the anode compared with serum alpha 1PI on ...
History of psychiatryFebruary 18, 2006
Volume 16, Issue Pt 4 (no 64) 467-471 doi: 10.1177/0957154X05051459
Papakostas YG, Daras MD, Liappas IA, Markianos M.Anthropophagic horses have been described in classical mythology. From a current perspective, two such instances are worth mentioning and describing: Glaucus of Potniae, King of Efyra, and Diomedes, King of Thrace, who were both devoured by their horses. In both cases, the horses' extreme aggression and their subsequent anthropophagic behaviour were attributed to their madness (hippomania) induced by the custom of feeding them with flesh. The current problem of 'mad cow' disease (bovine spongiform encephalopathy) is apparently related to a similar feed pattern. Aggressive behaviour in horses c...
Otcenásek M, Mátl J, Vítovec J, Vladík P, Wohlman J.A case of maduromycotic mycetoma (eumycetoma) in seven years old draught horse is described. The disease was localized in anal region and healed after surgical treatment. Attention is drawn to the necessity of distinguishing three types of mycosis in horses, characterized by the origin of tumor lesions - mycetomas, hyphomycosis and entomophthoromycosis - and information was gathered on their etiology and geographical occurrence. On the basis of the morphology of fungal elements traced in inflammated changed tissues and with regard to the existing findings on the origin of eumycetoma in animals...
Foreman JH.Metabolic causes of exercise intolerance can be subtle and difficult to document in horses. Because of increased metabolic rate in exercising muscle, most metabolic causes of exercise intolerance are clinically manifested by muscle abnormalities such as ER. Newer causes of ER are being documented by current research and are summarized in the article on muscular causes of equine exercise intolerance. Endocrine causes of exercise intolerance have been poorly documented, but recent work has shown the detrimental effects of hypothyroidism on exercise tolerance in horses. Many metabolic manifestati...
Grünig G, Von Fellenberg R, Maier R, Corboz L.Seventeen out of 21 horses had pulmonary microbial organisms which reached considerable numbers in seven cases. Elastase-producing microorganisms from the environment (Streptomyces species and to a lesser extent Bacillus species) constituted 22 per cent to 99 per cent (mean 79 per cent) of the total growth. There was a considerable number of microorganisms with in vitro-produced elastases which were not or only slightly affected by horse serum. There was no correlation between numbers of organisms and pulmonary histopathological findings thus the significance of these microorganisms in the pat...
Bowman SG, Marshall JF, Blikslager AT.To determine demographic characteristics of horses donated to the North Carolina State University Equine Health Center (EHC) between 1996 and 2008. Methods: Retrospective cohort study. Methods: 122 horses donated to the EHC between January 1996 and December 2008, and 246 horses offered for donation to the EHC between January 2007 and December 2008. Methods: Telephone and medical records were examined. Data were collected in 5 categories: age, sex, breed, reason for donation, and use prior to donation. Results: From January 1996 through December 2008, 122 horses were donated to the EHC (median,...
Rogerson BA, Condron RJ, Baker J, Craven JA.Inoculation of Haemophilus equigenitalis into the uterus of 7 mares caused a disease clinically indistinguishable from contagious equine metritis. The duration of clinical signs varied from 4 to 11 days. The causative organism persisted for a relatively short time (2 to 10 weeks) in 5 mares, but in 2 others it established a carrier status and persisted until they were killed 6 and 10 months after infection. H. equigenitalis was recovered from the vestibule of the vagina and from a combined swab of the clitoral fossa and sinuses throughout the course of the infection. In some mares there were e...
van Weeren PR, Denoix JM.Juvenile osteochondral conditions (JOCC) have a major impact on the equine industry and include many musculoskeletal disorders of the young horse, of which osteochondrosis (OC) is the most prominent. The Breeding, Osteochondral Status and Athletic Career (BOSAC) project is the first large, comprehensive, longitudinal field study on the subject conducted in three breeds of performance horses (Thoroughbreds, Standardbred Trotters and Warmbloods) that were monitored in their natural environment where they were reared under common field conditions. The BOSAC study used a radiographic protocol desi...
Costa F, Brunsting J, Corrêa F.This case report describes a 16-year-old jumping stallion that had a marked swelling over the left antebrachial area along with substantial lameness after a fall. The horse was weight bearing but lame (4/5; AAEP scale) at the walk with marked enlargement in the caudal aspect of the antebrachial region. After a static musculoskeletal examination, radiography and ultrasonography the horse was diagnosed with flexor muscle myopathy and presumptive extremity compartment syndrome. Following medical treatment, the horse improved clinically over several days. Six-months post injury the horse showed fl...
Tennent-Brown BS, Morrice AV, Reed S.Neonatal encephalopathy is the most common neurologic condition affecting newborn foals and shares similarities with perinatal asphyxia syndrome of human infants. In many cases of neonatal encephalopathy there is no obvious episode of acute or chronic hypoxia and other mechanisms likely play a role in the pathogenesis. Increased concentrations of neuroactive progestagens are found in affected foals; whether these molecules are protective, as has been suggested, or play a role in the pathogenesis is unknown. Neurologic diseases other than neonatal encephalopathy affect foals occasionally and sh...
Bester RC, Coetzer JA.A case of granulomatous enteritis in a 2 year-old Thoroughbred colt is reported. Clinically the horse showed chronic wasting and subcutaneous oedema of the ventral parts of the body and legs. Grossly the wall of the jejunum and ileum was uniformly thickened. Microscopically the lamina propria, submucosa and the tunica muscalaris of the small intestine were infiltrated with lymphocytes, plasma cells, epithelioid cells and occasional multinucleated giant cells. The granulomatous reaction was most marked in the muscular layers of the gut wall.
Boswinkel M, Neyens IJ, Sloet van Oldruitenborgh-Oosterbaan MM.A 5-year old Tinker gelding was referred to the Department of Equine Sciences with a left eye uveitis and fever. At presentation the horse showed a mild lethargy, fever and decreased vision of the left eye. Rectal examination revealed an enlarged left kidney, with a hard and an irregular surface. The cranial mesentery artery had an enlarged and irregular aspect. Blood analysis showed anaemia, leucocytosis, increased blood urea nitrogen and creatinine and a hyperproteinemia. Urine analysis repeatedly showed a marked proteinuria and an increased gammaGT/creatinine ratio. The amount of abdominal ...
