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.
Haritou SJ, Zylstra R, Ralli C, Turner S, Tortonese DJ.Equine pituitary pars intermedia dysfunction (PPID) is a common and serious condition that gives rise to Cushing's disease. In the older horse, it results in hyperadrenocorticism and disrupted energy metabolism, the severity of which varies with the time of year. To gain insight into the mechanism of its pathogenesis, 24-h profiles for peripheral plasma melatonin, serotonin, dopamine and cortisol concentrations were determined at the winter and summer solstices, and the autumn and spring equinoxes in six horses diagnosed with Cushing's disease and six matched controls. The nocturnal rises in p...
Rakesh V, Datta AK, Ducharme NG, Pease AP.Computational model for airflow through the upper airway of a horse was developed. Previous flow models for human airway do not hold true for horses due to significant differences in anatomy and the high Reynolds number of flow in the equine airway. Moreover, models that simulate the entire respiratory cycle and emphasize on pressures inside the airway in relation to various anatomical diseases are lacking. The geometry of the airway was created by reconstructing images obtained from computed tomography scans of a thoroughbred racehorse. Different geometries for inhalation and exhalation were ...
Vandekerckhove A, Glorieux S, Broeck WV, Gryspeerdt A, van der Meulen KM, Nauwynck HJ.An in vitro model of the upper respiratory tract of the horse was developed to investigate mechanisms of respiratory diseases. Four tissues of the upper respiratory tract of three horses were collected. Explants were maintained in culture at an air-liquid interface for 96h. At 0, 24, 48, 72 and 96h of cultivation, a morphometric analysis was performed using light microscopy, scanning electron microscopy and transmission electron microscopy. The explants were judged on morphometric changes of epithelium, basement membrane and connective tissue. Viability was evaluated using a fluorescent Termin...
Vinogradov E, MacLean LL, Brooks BW, Lutze-Wallace C, Perry MB.Taylorella asinigenitalis sp. nov is a nonpathogenic gram-negative bacterium recently isolated from the genital tract of male donkeys. The bacterium is phenotypically indistinguishable from Taylorella equigenitalis, a pathogen that is the cause of contagious equine metritis, a highly communicable venereal disease of horses. The structural analysis of the lipopolysaccharide produced by T. asinigenitalis sp. nov (ATCC 700933) demonstrated that its O-polysaccharide (O-PS) component is a linear unbranched polymer of repeating disaccharide units composed of 1,3-linked pyranosyl residues of 2,4-diac...
Firshman AM, Valberg SJ, Baird JD, Hunt L, DiMauro S.To determine insulin sensitivity, proportions of muscle fiber types, and activities of glycogenolytic and glycolytic enzymes in Belgians with and without polysaccharide storage myopathy (PSSM). Methods: 10 Quarter Horses (QHs) and 103 Belgians in which PSSM status had been determined. Methods: To determine insulin sensitivity, a hyperinsulinemic euglycemic clamp (HEC) technique was used in 5 Belgians with PSSM and 5 Belgians without PSSM. Insulin was infused i.v. at 3 mU/min/kg for 3 hours, and concentrations of blood glucose and plasma insulin were determined throughout. An i.v. infusion of g...
Anderson JD, Galuppo LD, Barr BC, Puchalski SM, Macdonald MM, Whitcomb MB, Magdesian KG, Stover SM.To describe clinical and scintigraphic abnormalities in horses with a bone fragility disorder. Methods: Retrospective case series. Methods: 16 horses with scintigraphic evidence of multiple sites of increased radiopharmaceutical uptake (IRU). Procedures-Medical records were reviewed for information on signalment; history; clinical, clinicopathologic, and diagnostic imaging findings; and treatment. Follow-up information was obtained through telephone interviews with owners. Results: Horses ranged from 4 to 22 years old; there were 8 castrated males and 8 females. Foci of IRU most commonly invol...
Arroyo LG, Vengust M, Dobson H, Viel L.A 10-day-old quarter horse colt was presented for signs of disorientation and inability to nurse. Hydronephrosis/hydroureters, with concomitant pyelonephritis and a severe electrolytes disturbance, were diagnosed. The clinical findings closely resembled those described for a syndrome of transient pseudohypoaldosteronism in human neonates. Un poulain Quarter horse âgé de 10 jours a été présenté pour des signes de désorientation et d’incapacité à se nourrir. Une hydronéphrose/hydrouretères avec pyélonéphrite concomitante et débalancement électrolytique sévère ont été diagno...
Ramzan PH, Marr CM, Meehan J, Thompson A.A novel radiographic projection is described for assessing part of the temporomandibular articulation of horses. It minimises the superimposition of osseous structures of the cranium that limit the usefulness of conventional projections and permits improved imaging in cases of suspected disease.
le Jeune SS, Nieto JE, Dechant JE, Snyder JR.Gastroscopic examinations were performed in 62 Thoroughbred broodmares (33 pregnant, 29 non-pregnant) at one breeding farm to investigate the prevalence of gastric ulceration. Age, pregnancy status, race earnings, last race start, herd size, medical history, number of live foals, breeding years, feed type and number of feedings were recorded, plus coat condition and body condition score were determined. Twenty-one mares were re-evaluated after foaling, and the foaling date, foal weight at birth and placenta weight were recorded. The overall prevalence of gastric ulcers was 70.9%, with a median...
Wild TF.Paramyxoviruses have been implicated in both animal and human infections. Some viruses, such as Morbilliviruses are responsible for large-scale epidemics. However, there are limited observations of these viruses crossing the host species barrier in nature. In 1994, in Australia a fatal infection in horses and humans was identified to be caused by a new Paramyxovirus, Hendra virus (HeV), and in 1998 in Malaysia, a closely related virus, Nipah virus (NiV) was responsible for fatal infections in pigs and humans. These two viruses were sufficiently different from previously described Paramyxovirus...
Leblanc MM.Most equine infertility cases can be solved with a methodical, thorough physical and reproductive examination and appropriate diagnostic laboratory aids. Repeated examinations may be needed in some cases to identify subtle anatomical abnormalities or irregularities between hormonal and physiological relationships of the reproductive tract. For pregnancy to occur, hormonal signaling must be exquisitely synchronized with physical changes of the reproductive tract and deposition of fertile semen in the uterus. Asynchrony of these events, infection, inflammation, previous trauma to the reproductiv...
Probst A, Macher R, Hinterhofer C, Polsterer E, Guarda IH, König HE.This study aims to elucidate the topographical anatomy of the carpal flexor retinaculum or palmar anular carpal ligament (PACL) in the horse. Ten specimen of the carpus of five healthy horses were studied by dissection in layers. Slices of 5 mm in thickness facilitated observation of the soft tissues. The superficial layer of the PACL subdivides into five compartments: one for the palmar nerve and the arterial and venous branches, one for only the radial artery, one for the radial vein, and one for the tendon of the radial carpal flexor muscle, and finally for the deep layer that supports all ...
Liu IK, Troedsson MH.Diagnosis and treatment of endometritis in the mare has been controversial and mostly empirical. The lack or inability of researchers to establish or develop a model that can serve as a standard or control makes this area of equine reproduction difficult to address scientifically. However, major advances have been made, particularly with the demonstration of the importance of uterine contractility in the elimination of bacteria, fluid, and inflammatory products from the uterus after breeding. This review provides a historical perspective of what has been done, and where we are now, in the appr...
Araújo JA, Curcio B, Alda J, Medeiros RM, Riet-Correa F.Two outbreaks of Hypochaeris radicata-induced Australian stringhalt involving two farms and seven horses from southern Brazil are reported here. Subsequently, the disease was experimentally reproduced in a feeding trial with one colt fed H. radicata from the suspect paddocks. Fresh H. radicata was fed to the experimental animal for 50 days at an average daily dosage of 9.8 kg. Initially, the plant was collected from the paddock where the clinical disease occurred and was fed for 19 consecutive days producing mild clinical signs. However, on days 20-23 fresh plant was collected from a neighbori...
Turton JF, Baklan H, Siu LK, Kaufmann ME, Pitt TL.A multiplex PCR using targets within the serotype-specific region of the capsular polysaccharide synthesis gene cluster of serotypes K1, K2 and K5 was evaluated using the 77 reference serotype strains of Klebsiella, and a panel of clinical isolates subjected previously to conventional serotyping. The PCR was highly specific for these serotypes, which are those most associated with virulence in humans and horses. PCR confirmed that isolates of the K5 serotype had cross-reacted with antiserum for other serotypes, particularly for K7. K5 isolates received by our laboratory were almost exclusively...
Scocco P, Pedini V.This study was performed to identify the equine respiratory tract areas which express the specific receptor for equine influenza virus; findings may be useful to provide new ways to treat the infectious disease. The present work aims to visualize in situ the presence of sialoderivatives in the horse respiratory tract in order to localize sialoderivatives acting as influenza virus receptors. To this purpose, nasal mucosae, trachea, bronchus and lung parenchyma were removed from 8 mature horses of both sexes. We performed sialic acid characterization by means of mild and strong periodate oxidati...
Gehlen H, Oey L, Rohn K, Bilzer T, Stadler P.Chronic pulmonary diseases (recurrent airway obstruction [RAO]) have been reported to alter skeletal muscle cells in humans. The purpose of this study was to evaluate a potential relationship between pulmonary and muscle variables in horses with a clinical diagnosis of RAO. Muscle biopsies from healthy horses and from horses with RAO were investigated and the relationship between the severity of lung disease and the degree of muscular changes was determined. Objective: We hypothesized that chronic pulmonary disease can lead to changes of the skeletal muscle in horses. Methods: Fifteen healthy ...
Ryhner T, Müller N, Balmer V, Gerber V.The mechanisms leading to mucus accumulation in equine inflammatory airway disease (IAD) and recurrent airway obstruction (RAO) are unclear. In airways of human patients with asthma and/or chronic obstructive pulmonary disease as well as in animal models of these diseases, associations of mucus hyperproduction with increased calcium-activated chloride channel 1 (CLCA1), epidermal growth factor receptor (EGFR), mucin 5AC (MUC5AC), B-cell lymphoma 2 (Bcl-2), interleukin (IL)-13 and interferon (IFN)-gamma expression have been reported. We hypothesized that increased mucus accumulation in RAO and ...
Ishii M, Kobayashi S, Acosta TJ, Miki W, Yamanoi T, Matsui M, Miyake Y, Miyamoto A.The aim of this study was to clarify the relationship between circulating oxytocin (OT) and PGF(2alpha) metabolite (PGFM) in mares at the third stage of labor and placental expulsion time in order to investigate a cause of retained placenta of which the incidence increase in a heavy draft mare. Blood was sampled every 5 min from foaling to expulsion of the placenta in 18 heavy draft mares to evaluate circulating OT and PGFM. The relationships between OT and PGFM concentration and recorded placental expulsion times were investigated. The results were as follows (1) The highest level of OT conce...
Perelygin AA, Zharkikh AA, Astakhova NM, Lear TL, Brinton MA.Chemokine receptors (CCRs) play an essential role in the initiation of an innate immune host response. Several of these receptors have been shown to modulate the outcome of viral infections. The recent availability of complete genome sequences from a number of species provides a unique opportunity to analyze the evolution of the CCR genes. A phylogenetic analysis revealed that the CCR2 gene evolved in concert with the paralogous CCR5 gene, but not with another paralogous gene, CCR3, in the opossum, platypus, rabbit, guinea pig, cat, and rodent lineages. In addition, evidence of concerted evolu...
Cheetham J, Pigott JH, Thorson LM, Mohammed HO, Ducharme NG.The laryngeal tie-forward procedure (LTFP) is becoming widely used for correction of dorsal displacement of the soft palate (DDSP) despite the absence of an evidence-based assessment of its efficacy. Objective: The LTFP returns racing performance to preoperative baseline levels and to that of matched controls; and post operative laryngohyoid position is associated with post operative performance. Methods: Case-controlled study of racehorses undergoing a LTFP for dorsal displacement of the soft palate at Cornell University between October 2002 and June 2007. Methods: The presence of at least on...
Mele M, Ramseyer A, Burger D, Brehm W, Rieder S, Marti E, Straub R, Gerber V.Many of the important diseases of sport and pleasure horses are thought to have a genetic component. The majority of these diseases, however, are multifactorial and are influenced not only by genetics, but also by environmental factors. In this review some of the most important multifactorial diseases are described and the current evidence for a genetic background is discussed.
Mele M, Ramseyer A, Burger D, Leeb T, Gerber V.Overall, monogenetic hereditary diseases are less important for the breeding industry than polygenetic diseases because they are relatively rare. For the individual animal, however, these diseases have often a dramatic outcome and many of these diseases presently known are lethal. For several of them the exact pathogenesis is known and DNA-tests are available to confirm the exact diagnosis.
Reardon RJ, Fraser BS, Heller J, Lischer C, Parkin T, Bladon BM.There have been no reports of the efficacy of thermocautery of the soft palate (TSP) assessed objectively as a treatment of intermittent dorsal displacement of the soft palate (DDSP). Objective: To compare: racing performance of horses that underwent thermocautery of the soft palate with matched controls; and 'Racing Post ratings' (RPR) with prize money won (RE) and a performance index (PI) for each of the horses in the study. Objective: Thermocautery of the soft palate has no beneficial effect on racing performance and the 3 measures of performance are significantly related. Methods: The incl...
Lichtenfels JR, Kharchenko VA, Dvojnos GM.The Equidae (the horse, Equus caballus, the ass, Equus asinus, zebras and their hybrids) are hosts to a great variety of nematode parasites, some of which can cause significant morbidity or mortality if individual hosts are untreated. Worldwide the nematode parasites of horses belong to 7 suborders, 12 families, 29 genera and 83 species. The great majority (19 of 29 genera and 64 of 83 species) are members of the family Strongylidae, which includes the most common and pathogenic nematode parasites of horses. Only the Strongylidae are included in this treatise. The Strongylidae (common name str...
Macpherson ML, Bailey CS.Placental infections in the mare are a diagnostic and therapeutic challenge. The following article will review techniques for identifying placental infections, approaches for treating placentitis, and methods for managing these mares after foaling.
Archer DC, Pinchbeck GL, French NP, Proudman CJ.Epiploic foramen entrapment (EFE) is a common cause of small intestinal strangulation in the horse and its epidemiology requires further investigation. Objective: To identify horse- and management-level risk factors for EFE and to explore reasons for the apparent seasonality of this condition. Objective: Horses exhibiting certain behaviours and those exposed to particular management practices that vary seasonally are at increased risk of EFE. Methods: A prospective unmatched, multicentre case-control study was conducted over 24 months in the UK. Data on 77 cases and 216 control horses were obt...
Magnarelli L, Fikrig E.Blood samples were collected from 98 horses suspected of having borreliosis or granulocytic ehrlichiosis in Connecticut and New York State, USA during 1985, 1995, and 1996. Serum antibodies to Borrelia burgdorferi were detected by an enzyme-linked immunosorbent assay (ELISA), based on whole-cell and recombinant antigens, in 82 (84%) horses. Of the 181 sera tested, 59% were positive, using whole-cell antigens, compared to 48% with protein (p)37 and 35% with VlsE antigens. An ELISA containing either of these fusion proteins can be used as an adjunct to general screening by an ELISA or immunoblot...
Chapman SW, Metzger N, Grest P, Feige K, von Rechenberg B, Auer JA, Hottiger MO.Gray horses spontaneously develop metastatic melanomas that resemble human disease, and this is often accompanied with metastasis to other organs. Unlike in other species, the establishment of primary equine melanoma cultures that could be used to develop new therapeutic approaches has remained a major challenge. The purpose of the study was to develop a protocol for routine isolation and cultivation of primary equine melanocytes. Melanoma tissues were excised from 13 horses under local anesthesia, mainly from the perianal area. The melanoma cells were isolated from the melanoma tissue by seri...
Bertram TA, Coignoul FL, Jensen AE.Equine neutrophils were combined with Haemophilus equigenitalis (contagious equine metritis organism; CEMO) or Escherichia coli in low- and high-antibody-titer serum to evaluate the neutrophils ability to phagocytize and kill these bacteria. More E. coli than CEMO were phagocytized at each time period. After 120 min in low-antibody-titer serum, 56.3% of the E. coli and 34.3% of the CEMO were phagocytized. A total of 45% of CEMO and 74.9% of E. coli were phagocytized by 120 min when neutrophils were in high-antibody-titer serum. More than 75% of the ingested E. coli and 90% of the ingested CEMO...
Pickar JG, Spier SJ, Snyder JR, Carlsen RC.A recently described disorder in certain registered Quarter horses bears many clinical similarities to the muscle disease identified as hyperkalemic periodic paralysis (HPP) in humans. Pathological changes in membrane permeability or Na(+)-K+ pump activity have been proposed to produce the muscle depolarization and inexcitability that characterize the condition in humans. Biopsies of external intercostal muscle from normal and affected horses were used to determine whether alterations in either permeability and/or pump activity could be linked to the pathology in horses. Affected horse muscle ...
Semik-Gurgul E.Sarcoids are the most commonly diagnosed skin tumours in equines. Bovine papillomaviruses (BPVs) are the primary causative agent of sarcoids. There has been intensive research to discover the molecular mechanisms that may contribute to the aetiopathogenesis of this disease and tumour suppressors and proto-oncogenes known to play a role in human neoplastic conditions have been investigated in equine sarcoids. Current approaches include the identification of gene expression profiles, characterising sarcoid and normal skin tissues, and an assessment of epigenetic alterations such as microRNA diff...
Carroll JF, Schmidtmann ET.The American dog tick, Dermacentor variabilis (Say), was the only ixodid tick found feeding on horses in Montgomery County, Md., from May to August. Average tick burdens were low (less than one tick per horse per week), but >80% of 33 horses examined weekly were exposed to tick feeding during the summer. Of the 98 ticks collected, 78% were attached to the tail and 12% were present in the mane. Host-seeking adult D. variabilis were active on vegetation in pastures from May to early August, with most specimens along hedgerows, woods margins, and horse paths.
Adepu S, Lord M, Hugoh Z, Nyström S, Mattsson-Hulten L, Abrahamsson-Aurell K, Lützelschwab C, Skiöldebrand E.We aimed to delineate a novel soluble Biglycan Neo-epitope-BGN262 in saliva from young reference and osteoarthritic horses in conjunction with the influence of short-term training exercise, riding surface hardness, circadian rhythm, and feeding on its soluble levels. Unassigned: A custom-made inhibition ELISA was used for the quantification of BGN262 in saliva. Cohort 1: A cross-sectional study comprising reference (N = 19) and OA horses (N = 9) with radiographically classified subchondral bone sclerosis. Receiver operating characteristic curve analysis was performed to evaluat...
Pinkerton ME, Bailey KL, Thomas KK, Goetz TE, Valli VE.A 17-year-old Quarterhorse gelding with a clinical diagnosis of protein-losing enteropathy was submitted for necropsy following a 4-5-month duration of weight loss, decreased appetite, and hypoproteinemia. Gross findings included multiple 1-2-cm diameter ulcers on the luminal surfaces of the duodenum and ileum. Histologic examination revealed individual large, round cells infiltrating much of the mucosal epithelium of the duodenum, jejunum, ileum, and colon in addition to multifocal areas of ulceration. Similar round cells infiltrated Brunner's glands and expanded the submucosa beneath the foc...
Dacre IT, Shaw DJ, Dixon PM.Histological measurements of dimensions of primary, regular secondary and irregular secondary dentine, pulp diameter and assessment of the levels of predentine, resting lines and enlarged areas of intertubular dentine were performed in apically infected mandibular and maxillary cheek teeth (CT). These examinations showed significantly reduced regular and irregular secondary dentine thickness in diseased as compared to control CT, with 21/26 infected maxillary CT and 15/18 infected mandibular CT having reduced regular secondary dentine (varying between 27.4% and 89.1% reduced secondary dentine ...
Frye MA.Equine urinary tract infection (UTI) most commonly occurs as a sequela to structural or functional inhibition of normal urine flow. Although it is an infrequent diagnosis in equids, the incidence of UTI in human beings is high and has inspired great investigative effort. The resultant findings with potentially broad application as well as current equine studies are reviewed here. Recent developments in the understanding of host-agent interactions and renal defense mechanisms, emerging antimicrobial resistance, and novel therapeutic alternatives to prophylactic antibiotic use are emphasized.
Darien BJ, Belknap J, Nietfeld J.Two horses with cerebrospinal nematodiasis (Micronema deletrix) had signs similar to those of other neurologic diseases resulting from parasitic (fly larvae, protozoa, or other helminths) migration through the central nervous system (CNS). In one horse (horse 1), a 13-year-old Paso Fino stallion, the cerebrospinal fluid (CSF) was slightly xanthochromic (1+), with a pleocytosis (25 nucleated cells/microliter) and a normal protein level (69 mg/dl). A CSF differential cell count showed 15% neutrophils, 56% lymphocytes, 22% macrophages, 5% eosinophils, and 2% basophils. In the other horse (horse 2...
Raudsepp T.Reproductive disorders are genetically heterogeneous and complex; available genetic tests are limited to chromosome analysis and 1 susceptibility gene. Cytogenetic analysis should be the first test to confirm or rule out chromosomal aberrations. No causative genes/mutations are known. The only available genetic test for stallion subfertility is based on a susceptibility gene FKBP6. The ongoing progress in equine genomics will improve the status of genetic testing. However, because subfertile phenotypes do not facilitate collection of large numbers of samples or pedigrees, and clinical causes o...
Garner A, Griffiths P.The purpose of this paper is to describe congenital defects, having no direct counterpart in
the literature, that affected both eyes of a new-born foal of pedigree racing stock, which
otherwise appeared to be entirely healthy as were both the sire and the dam.
Eydt C, Schröck C, Geburek F, Rohn K, Staszyk C, Pfarrer C.The sternum is a frequently used anatomical site to obtain bone marrow for diagnostic and therapeutic purposes in equine medicine and surgery. For a safe and reproducible aspiration of sternal bone marrow, a reliable anatomical description of the sternum is mandatory. However, the anatomical literature provides very heterogeneous information concerning the structure and number of sternebrae. Isolated sterna (horses of different ages) underwent clinical computed tomography, and single sternebrae were scanned by microcomputed tomography. Data sets were analysed in detail, the dimensions of each ...