Disease diagnosis in horses involves the identification and characterization of illnesses through various diagnostic methods and tools. This process is essential for effective veterinary care and management of equine health. Techniques used in diagnosing diseases in horses include clinical examinations, laboratory tests, imaging modalities such as ultrasonography and radiography, and molecular diagnostics. Blood tests are frequently utilized to assess parameters such as complete blood count and biochemical profiles, which can indicate underlying health issues. Additionally, advancements in genetic testing and biomarker identification have enhanced the ability to detect specific diseases early. This page aggregates peer-reviewed research studies and scholarly articles that explore diagnostic methodologies, their applications, and their impact on equine health management.
Research in microbiologyFebruary 11, 2003
Volume 154, Issue 1 29-35 doi: 10.1016/s0923-2508(02)00003-7
Silva TA, Rodrigues PH, Ribeiro RN, Noronha FS, Farias Lde M, Carvalho MA.The influence of growth medium, hemin and menadione, blood source and atmosphere of incubation on the expression of hemolytic activity of 25 strains of Prevotella intermedia and Prevotella nigrescens was evaluated. The best hemolytic activity was observed for samples of both species growing in brain heart infusion agar and incubated in Brewer-like anaerobic jars for 48 h. Hemolysis was less intense and occurred later in the presence of hemin and menadione in solid media. beta-Hemolysis was detected for medium supplemented with horse or human blood and alpha-hemolysis was observed when sheep bl...
McGowan CM, Menzies-Gow NJ, McDiarmid AM, Patterson-Kane JC.This paper describes four cases of equine polysaccharide storage myopathy which were confirmed by histological examination of muscle biopsy specimens. The horses were of mixed breeding, with warmblood and thoroughbred dominating. They all had recurrent episodes of rhabdomyolysis, indicated by clinical signs and increased plasma levels of muscle enzymes. They were managed conservatively and have continued athletic careers despite their disease.
Hirata H, Xuan X, Yokoyama N, Nishikawa Y, Fujisaki K, Suzuki N, Igarashi I.The efficacy of the Be82 gene product fused with glutathione S-transferase (GST/Be82) in an enzyme-linked immunosorbent assay (ELISA) for the diagnosis of Babesia equi infection was reported previously (H. Hirata et al., J. Clin. Microbiol. 40:1470-1474, 2002). However, the ELISA with the GST/Be82 antigen cross-reacted with Babesia caballi-infected horse sera, despite the high rate of detection of B. equi. These results suggested that GST/Be82 has an antigen in common with B. caballi or antigenicity similar to that of B. caballi. In the present study, we constructed a series of five clones wit...
Berezowski C.A 14-year-old quarter horse mare had a 2-year history of infertility and the presence of a mass in the right uterine horn. Prior to surgery, the mass was determined to be invasive by using ultrasonography and hysteroscopy. A partial ovariohysterectomy was performed. The mass was diagnosed histologically as a uterine leiomyoma.
Beck NF, Khalid M, Charles JM, Abbas SK, Care AD.The objective of the present study was to determine whether parathyroid hormone-related peptide (PTHrP) is present in the equine follicular fluid and if so, how it is related to the follicular development in the horse. For this purpose, ovaries were collected from 40 Thoroughbred and Thoroughbred Cross mares at slaughter during the period from February to May. Normal growing follicles were dissected from the ovaries of each mare and their diameters measured. A total of 174 follicles was used in this study. The follicular fluid was aspirated from each follicle and assayed for PTHrP, oestradiol ...
Cohen ND, Carey VJ, Donahue JG, Seahorn JL, Donahoe JK, Williams DM, Harrison LR.To identify factors associated with abortions of mares during late gestation attributed to mare reproductive loss syndrome (MRLS). Methods: Case-control study. Methods: 282 broodmares from 62 farms in central Kentucky, including 137 mares that had late-term abortions (LTAs) associated with MRLS, 98 mares from the same farms that did not abort, and 48 mares that aborted from causes other than MRLS. Methods: Farm managers were interviewed to obtain data on a wide range of management practices and environmental exposures for the mares. Data for case and control horses were compared to identify ri...
Cohen ND, Donahue JG, Carey VJ, Seahorn JL, Piercy D, Donahoe JK, Williams DM, Brown SE, Riddle TW.To identify factors associated with abortions during early gestation classified as mare reproductive loss syndrome (MRLS). Methods: Case-control study. Methods: 324 broodmares from 43 farms in central Kentucky, including 121 mares from 25 farms that had early-term abortions (ETAs) associated with MRLS (case horses), 120 mares from the same farms but that did not abort, and 83 mares from 18 farms that were not severely Impacted by MRLS. Methods: Farm managers were interviewed to obtain data on various management practices and environmental exposures for the mares. Data for case and control hors...
Ruohoniemi M, Ahtiainen H, Ojala M.Ossification of the cartilages in the foot is common in coldblooded horses, but prevalence as well as ossification pattern varies between breeds; research on estimation of heritability for the condition has been limited. Objective: Our purpose was to calculate estimates of 1) heritability for ossification parameters of the cartilages in the front feet of the Finnhorse and 2) genetic correlations between the different ossification parameters. Methods: Estimates of heritability for different ossification parameters of the cartilages in the front feet and of genetic correlations between different...
Schambourg MA, Laverty S, Mullim S, Fogarty UM, Halley J.Thoracic trauma occurs in newborn foals and may cause associated clinical signs; this condition remains poorly documented. Objective: The purpose of this study was to describe the pathological features of thoracic trauma in newborn foals presented for necropsy examination between 1990 and 2000. Methods: Necropsy reports of foals with thoracic trauma from 1990-2000 were reviewed. Subject details, clinical signs, thoracic and abdominal lesions were noted and analysed statistically. Results: Sixty-seven (9%) of 760 necropsied foals had thoracic trauma. In 19 foals, fractured ribs were considered ...
Prince D, Corcoran BM, Mayhew IG.Equine grass sickness is a dysautonomia characterised by widespread destruction of autonomic ganglia, resulting in the clinical signs of dysphagia, constipation, profuse sweating, tachycardia, rhinitis sicca and high mortality rate. Rhinitis sicca is a common finding in horses with the chronic form and we have postulated that alterations in autonomic innervation of the nasal mucosa might underlie this clinical presentation. Objective: In this study, the expression and distribution of nerve fibres immunoreactive for calcitonin gene-related peptide (CGRP), substance P (SP), the general neuronal ...
Akiba M, Uchida I, Nishimori K, Tanaka K, Anzai T, Kuwamoto Y, Wada R, Ohya T, Ito H.Equine paratyphoid is caused by Salmonella enterica serovar Abortusequi, and manifests mainly as abortion in the mare. We compared S. Abortusequi strains isolated in Japan and other countries using pulsed-field gel electrophoresis (PFGE) and fluorescent amplified-fragment length polymorphism (FAFLP) analysis. PFGE analysis of S. Abortusequi strains gave 21-27 fragments ranging in size from 33 to 602kb. Although two PFGE profiles were observed among the 20 S. Abortusequi isolates in Japan, the restriction fragments originating from the chromosome were common between the two profiles. The simila...
van Weeren PR, Knaap J, Firth EC.To elucidate the highly contentious role of copper in the pathogenesis of osteochondrosis. Objective: There would be no relationship between liver copper concentration of mares and foals and incidence of radiographically detectable osteochondrotic lesions in foals and yearlings was tested. Methods: Liver copper concentration was assessed in biopsies taken within 4 days after birth from both mares and foals and from the same foals at age 5 months. Biopsies were taken in the standing, sedated animal under ultrasonographic guidance. Radiographs were taken of both hocks (lateromedial, dorsoplantar...
Dyson S, Murray R, Schramme M, Branch M.Foot pain is a common cause of equine lameness and there have been significant limitations of the methods available for the diagnosis of the causes of foot pain (radiography, nuclear scintigraphy and ultrasonography). Until recently, magnetic resonance imaging (MRI) in the horse has been limited to examination of cadaver limbs. Objective: Our purpose was to 1) describe MRI of the foot in live horses, 2) describe MRI findings in horses with foot pain in which a definitive diagnosis could not be established by alternative means and 3) correlate MRI findings with other methods of clinical investi...
Tomlinson JE, Sage AM, Turner TA.The pelvis is covered with extensive musculature and often presents a challenge in diagnostic imaging. Ultrasonography provides diagnostic information about soft tissue, articular cartilage and bone surfaces, although little information exists about the normal ultrasonographic appearance of the equine sacroiliac region. Objective: To determine the clinical applicability of ultrasonographic examination in horses with sacroiliac pain. Methods: Horses presented to the University of Minnesota Veterinary Teaching Hospital for hindlimb lameness were evaluated and lower limb lameness was ruled out wi...
Sutton DG, Bahr A, Preston T, Christley RM, Love S, Roussel AJ.Disordered gastric motility may be a significant factor in the pathogenesis of many equine conditions. Although tests for liquid phase emptying rate have been validated in the horse, there are no effective tests for solid phase emptying measurement that can be performed routinely in the field. Objective: The objective of this study was the assessment of a novel stable isotope technique, the 13C-octane acid breath test (13C-OABT), for the measurement of gastric emptying of solid ingesta, by direct comparison with the optimum method of gastric scintigraphy. Methods: To facilitate dual measuremen...
Peek SF, Semrad SD, Perkins GA.Previous reports of clostridial myonecrosis have either focused on individual case reports or have been small retrospective studies reporting very high mortality rates. Objective: The objective of this study was to describe the outcome of cases of clostridial myonecrosis submitted to 2 referral equine hospitals in the United States over a 15 year period. Methods: A retrospective study of case material selected on the basis of positive Clostridium spp. culture or the identification of Clostridium spp. by specific fluorescent antibody testing from soft tissue wounds was performed at Cornell and ...
Gläser KE, Davies ME, Jeffcott LB.This study was designed to examine a new role for cysteine proteinases in the process of endochondral ossification. Objective: The aim of the present study was to investigate the presence and distribution of cathepsin B and cathepsin L in equine articular cartilage during development. Methods: Full-depth cartilage samples from a total of 40 horses (age range: 4 month fetuses to 2 years) were examined and enzymes detected by immunocytochemical localisation. Results: Observations on the presence of cathepsins B and L revealed significant age-related differences, resulting in clear division of th...
Dagleish MP, Brazil TJ, Scudamore CL.Lipopolysaccharide (LPS) and N-formyl-methionyl-leucyl-phenylalanine (fMLP)-like peptides are Gram-negative bacterial cell wall components which, when released into the peripheral circulation in endotoxaemia, have the potential to activate leucocytes. In vitro, equine neutrophils require priming with LPS in order to generate reactive oxygen intermediates (ROI) in response to fMLP. Objective: The aim of this study was to examine whether the release of other neutrophil products is similarly dependent on prior priming with LPS. In particular, neutrophil elastase (NE), a potent proteolytic enzyme,...
Jefcoat AM, Wagner JG, Robinson NE.The research article involves an in-depth exploration of the role of neutrophils, a type of immune cell, in inflammation, especially in relation to horse diseases. The study discusses the historical […]
Maury W, Wright PJ, Bradley S.A novel strain of equine infectious anemia virus (EIAV) called vMA-1c that rapidly and specifically killed infected equine fibroblasts (ED cells) but not other infectible cell lines was established. This strain was generated from an avirulent, noncytopathic strain of EIAV, MA-1. Studies with this new cytolytic strain of virus have permitted us to define viral parameters associated with EIAV-induced cell killing and begin to explore the mechanism. vMA-1c infection resulted in induction of rapid cell death, enhanced fusogenic activity, and increased rates of spread in equine fibroblasts compared...
Broekman LE, Kuiper D.After giving a descriptive definition of megaesophagus attention is paid to the occurrence, the possible causes and pathogeneses, the clinical history and diagnosis, age, breed and sex of the horses with megaesophagus, and the prognosis. The most important characteristics of megaesophagus are summarized in two tables referring to 11 cases published in the literature and 18 own cases. Finally some conclusions based on published as well as not published own cases are given.
Båverud V.In human medicine, Clostridium (C.) difficile is since many years a well-known cause of nosocomial diarrhea induced by antibiotic treatment. In horses, C. difficile was recently suggested as a possible enteric pathogen. The bacterium is associated with acute colitis in mature horses following treatment with antibiotics. C. difficile, and/or its cytotoxin, is also associated with acute colitis in mares when their foals are being treated with erythromycin and rifampicin for Rhodococcus equi pneumonia. The colitis can have resulted from an accidental ingestion of erythromycin by the mares. In an ...
The Journal of parasitologyJanuary 23, 2003
Volume 88, Issue 6 1239-1246 doi: 10.1645/0022-3395(2002)088[1239:QEOSTF]2.0.CO;2
Packham AE, Conrad PA, Wilson WD, Jeanes LV, Sverlow KW, Gardner IA, Daft BM, Marsh AE, Blagburn BL, Ferraro GL, Barr BC.Neospora hughesi is a newly recognized protozoan pathogen in horses that causes a myeloencephalitis similar to Sarcocystis neurona. There are no validated serologic tests using the gold standard sera that are currently available to detect specific N. hughesi antibodies and, thus, no tests available to detect antemortem exposure or estimate seroprevalence in the horse. The objectives of the present study were to establish a bank of gold standard equine sera through experimental infections with N. hughesi and to assess several serologic tests for the detection of related protozoan antibodies. Se...
The Journal of parasitologyJanuary 23, 2003
Volume 88, Issue 6 1130-1134 doi: 10.1645/0022-3395(2002)088[1130:GHOPIL]2.0.CO;2
Chapman MR, French DD, Klei TR.A survey in Louisiana of gastrointestinal helminths recovered at necropsy from 117 ponies with minimal exposure to anthelmintics between 1989 and 2000 is compared with a survey conducted 20 yr earlier in the same region. An objective of this study was to determine whether species diversity has been affected by the advent and use of the macrocyclic lactone (ML) parasiticides and by the increased anthelmintic pressure on the helminth species infecting the general equine population. Twenty-six cyathostome species and 8 strongyle species were recovered. Two cyathostome species that were not found ...
van der Meulen KM, Nauwynck HJ, Pensaert MB.Equine herpesvirus-1 (EHV-1) may cause abortion in vaccination- and infection-immune horses. EHV-1-infected peripheral blood mononuclear cells (PBMCs) play an important role in virus immune evasion. The mechanisms by which infected PBMCs can avoid destruction by EHV-1-specific antibody and equine complement were examined. The majority of EHV-1-infected PBMCs (68.6 %) lacked surface expression of viral antigens and these cells were not susceptible to complement-mediated lysis. In infected PBMCs with surface expression of viral antigens, 63 % showed focal surface expression, whereas 37 % showed ...
Hubert JD, Seahorn TL, Klei TR, Hosgood G, Moore RM.The purpose of this study was to compare concentrations of nitric oxide (NO) in fresh plasma versus frozen plasma, and determine the temporal effects of freezing on jugular venous plasma NO concentrations in clinically healthy ponies. Twenty-eight helminth-naive ponies, aged from 4 to 6 mo, were raised and maintained under parasite-free conditions. Blood was collected from the jugular vein, centrifuged, and the plasma supernatant was analyzed fresh for NO concentrations using a chemiluminescent method. The remaining samples were aliquoted into 12 samples and stored at -70 degrees C until they ...
Hill JA, Tyma JF, Hayes GM, Radcliffe R, Fubini SL.Obesity is common in the equine population and it has been associated with increased surgical morbidity and mortality in humans. The effect of increased body mass index (BMI) on the incidence of surgical site infections has not been investigated in horses. Objective: To determine whether horses with increased body fat, as estimated by BMI, are more likely to develop post-operative complications, particularly incisional complications, following emergency ventral midline celiotomy. Methods: Retrospective, multi-institutional clinical study. Methods: Medical records of horses >2 years old presen...
Reuss SM, Chaffin MK, Schmitz DG, Norman TE.The sonographic characteristics of intraabdominal abscesses in 11 foals and intraabdominal lymphadenitis in five foals with Rhodococcus equi infections are presented. Intraabdominal abscesses were usually present in the ventral abdomen adjacent to the ventral body wall, well-marginated, and contained a mixed or complex echo pattern. Lymphadenitis appeared as singular or multiple clusters of lymph nodes of mixed echogenicity adjacent to any portion of the gastrointestinal tract or body wall. Sonographic findings were supported by necropsy examinations, but sonographic measurements consistently ...
Björnström A, Blomström AL, Singh MC, Hesson JC.A number of viruses transmitted by mosquitoes are well known to cause disease in both humans and horses, ranging from mild fevers to mortal neurological disease. A recently discovered connection between the alphavirus Sindbis virus (SINV) and neurological disease in horses in South Africa initiated this serological study in northern Europe, where the same genotype of SINV (SINV-I) is also highly endemic. We tested 171 serum samples, originally obtained from horses for other reasons from April to October 2019, for presence of SINV neutralising antibodies using a plaque reduction neutralisation ...
Cohen ND, Loy JK, Lay JC, Craig TM, McMullan WC.A 3-year-old Quarter Horse gelding admitted for evaluation of weight loss, signs of depression, and dermatitis of the coronary bands was found to have eosinophilic gastroenteritis. Intralesional nematodes identified as Strongylus edentatus were seen in multiple microscopic sections of the small colon, suggesting a parasitic cause of the disease.
Gurfield N, Benirschke K.The placenta from a 300-day-gestational age, female, Arabian equine fetus was examined. Multifocal to coalescing, 0.5- to 4-cm-diameter, white, smooth nodules covered 50% of the placenta. Microscopic evaluation of the nodules revealed undifferentiated germ cells and a haphazard arrangement of immature, mesenchymal stroma, cartilage, squamous cornifying epithelium, scattered ducts and secretory acini lined by cuboidal to columnar epithelium, and mineralized foci. No umbilicus, arrangement about an axial skeleton, or organized polarity of structures was present. The lesion was diagnosed as a pla...
Lattimer J, Roberts H, Barnard M, Paterson A, Bell I, Hepple R, Holland S, George A.In early 2019, four stallions in the south of England tested positive for equine viral arteritis following routine prebreeding screening. Here, a team from Defra and the APHA describe the epidemiological investigation that was carried out to determine the origin of infection and the potential for its transmission across the country.
Perryman LE, McGuire TC, Hilbert BJ.Selective immunoglobulin M deficiency was diagnosed in 5 foals, on the basis of reduced serum immunoglobulin M concentrations (more than 2 standard deviations below the normal mean). All 5 foals had clinical signs or lesions involving the respiratory tract. Lkebsiella sp was isolated from joint fluids, bronchial lymph nodes, or tracheal washings from the 3 foals in which such samples were available for microbiologic evaluation.
Díaz S, Echeverría MG, It V, Posik DM, Rogberg-Muñoz A, Pena NL, Peral-García P, Vega-Pla JL, Giovambattista G.The polymorphism of equine lymphocyte antigen (ELA) class II DRA gene had been detected by polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP) and reference strand-mediated conformation analysis. These methodologies allowed to identify 11 ELA-DRA exon 2 sequences, three of which are widely distributed among domestic horse breeds. Herein, we describe the development of a pyrosequencing-based method applicable to ELA-DRA typing, by screening samples from eight different horse breeds previously typed by PCR-SSCP. This sequence-based method would be useful in high-throug...
Bolwell C, Gee E, Adams B, Collins-Emerson J, Scarfe K, Nisa S, Gordon E, Rogers C, Benschop J.The objectives of this study were to determine if horses located near an outbreak of leptospirosis in alpacas had titres indicative of a previous or current infection and, if so, to determine the magnitude in change of titres over time. Further, the objective was to determine if horses with high titre results were shedding in their urine. Blood samples were collected from twelve horses located on or next to the farm with the outbreak in alpacas, on day zero and at four subsequent time points (two, four, six and nine weeks). The microscopic agglutination test was used to test sera for five se...
Sanchez S, Studer M, Currin P, Barlett P, Bounous D.Listeria monocytogenes is ubiquitous in the environment but is rarely reported as a cause of keratitis in animals. In this case, a mare was presented with epiphora and evidence of pain in the right eye. Listeria monocytogenes was isolated from a corneal lesion, and bacteria were also seen in the cytologic evaluation. This is the first reported case of ulcerative keratitis associated with L. monocytogenes in a horse.
Kim I, Cohen ND, Roussel A, Wang N.Gastric emptying studies are of great interest in human and veterinary medical research to evaluate effects of medications or diets for promoting gastrointestinal motility and to examine unintended side-effects of new or existing medications, diets, or procedures. Summarizing gastric emptying data is important to allow easier comparison between treatments or groups of subjects and comparisons of results among studies. The standard method for assessing gastric emptying is by using scintigraphy and summarizing the nonlinear emptying of the radioisotope. A popular model for fitting gastric emptyi...
Stock KF, Distl O.To evaluate whether additive genetic correlations existed between certain aspects of the radiographic appearance of the distal sesamoid (navicular) bones (RNB) or between RNB and other types of radiographic changes in the limbs of Hanoverian Warmblood horses. Methods: 5,157 horses. Methods: Quasi-linear and binary traits were defined by the appearance of canales sesamoidales (CSs) and the structure and contour of the forelimb navicular bones (NBs). Prevalences of osseous fragments in the metacarphophalangeal and metatarsophalangeal (fetlock) and tarsocrural joints and deforming arthropathy in ...
Kopper JJ.Equine rotavirus is one of the most common causes of infectious diarrhea in foals. Although the infection itself is self-limiting, the resulting diarrhea is due to multiple mechanisms and can be severe, requiring supportive care including fluid and electrolyte support. Prompt diagnosis is important for treatment and biosecurity decisions and can be achieved by several means. Prevention, while imperfect, currently relies on vaccination of pregnant mares before parturition, ingestion of adequate colostrum from vaccinated mares and biosecurity measures.