Pathophysiology in horses involves the study of functional changes that occur in the body as a result of disease or injury. This field examines the mechanisms through which diseases develop and progress, as well as how they affect the body's normal physiological processes. In equine research, pathophysiology encompasses a wide range of conditions, including respiratory disorders, musculoskeletal injuries, gastrointestinal diseases, and metabolic syndromes. Understanding these processes helps in identifying potential therapeutic targets and developing effective treatment strategies. This page collects peer-reviewed research studies and scholarly articles that explore the underlying mechanisms, clinical manifestations, and implications of various pathophysiological conditions in equine health.
Blaettler C, Kaessmeyer S, Grabherr S, Koch C, Schweizer D, Van der Vekens E.In-depth understanding of pathophysiological processes occurring in the vasculature of the equine distal limb is of great importance to improve both diagnostic and therapeutic approaches to diseases. To gain further insights, a model allowing high-resolution 3D-visualization of the vasculature is necessary. This pilot study evaluated the feasibility of restoring vascular perfusion in frozen-thawed distal equine cadaver limbs without prior preparation using computer tomographic imaging (CT). Five frozen-thawed, radiographically normal forelimbs were perfused with a lipophilic contrast agent thr...
Muñoz-Prieto A, Contreras-Aguilar MD, Cerón JJ, Ayala I, Martin-Cuervo M, Gonzalez-Sanchez JC, Jacobsen S, Kuleš J, Beletić A, Rubić I, Mrljak V....Changes in the salivary proteome in 12 horses with the two diseases included in equine gastric ulcer syndrome (EGUS), equine glandular gastric disease (EGGD) (n = 6) and equine squamous gastric disease (ESGD) (n = 6), were evaluated using a high-resolution LC-MS/MS analysis of TMT-labelled peptides and compared to 10 healthy control horses. Serum was also analysed for comparative purposes. The comparison between the horses with EGGD and controls showed significant changes in 10 salivary proteins, whereas 36 salivary proteins were differently abundant between ESGD and control groups. The most u...
Podstawski P, Ropka-Molik K, Semik-Gurgul E, Samiec M, Skrzyszowska M, Podstawski Z, Szmatoła T, Witkowski M, Pawlina-Tyszko K.Matrix metalloproteinases (s) represent a family of enzymes capable of biocatalytically breaking down the structural and functional proteins responsible for extracellular matrix (ECM) integrity. This capability is widely used in physiological processes; however, imbalanced MMP activity can trigger the onset and progression of various pathological changes, including the neoplasmic transformation of different cell types. We sought to uncover molecular mechanisms underlying alterations in transcriptional profiles of genes coding for s, which were comprehensively identified in equine adult dermal ...
Niewiadomska J, Gajek-Marecka A, Gajek J, Noszczyk-Nowak A.Metabolic syndrome (MetS) is a disease that has a complex etiology. It is defined as the co-occurrence of several pathophysiological disorders, including obesity, hyperglycemia, hypertension, and dyslipidemia. MetS is currently a severe problem in the public health care system. As its prevalence increases every year, it is now considered a global problem among adults and young populations. The treatment of choice comprises lifestyle changes based mainly on diet and physical activity. Therefore, researchers have been attempting to discover new substances that could help reduce or even reverse t...
Roth SP, Burk J, Brehm W, Troillet A.Mesenchymal stromal cells (MSC) represent a promising treatment option for tendon disorders and joint diseases, primarily osteoarthritis. Since MSC are highly context-sensitive to their microenvironment, their therapeutic efficacy is influenced by their tissue-specific pathologically altered targets. These include not only cellular components, such as resident cells and invading immunocompetent cells, but also components of the tissue-characteristic extracellular matrix. Although numerous models have already shown potential MSC-related mechanisms of action in tendon and joint diseases, only a...
Simões J, Batista M, Tilley P.Severe equine asthma is a chronic respiratory disease of adult horses, occurring when genetically susceptible individuals are exposed to environmental aeroallergens. This results in airway inflammation, mucus accumulation and bronchial constriction. Although several studies aimed at evaluating the genetic and immune pathways associated with the disease, the results reported are inconsistent. Furthermore, the complexity and heterogeneity of this disease bears great similarity to what is described for human asthma. Currently available studies identified two chromosome regions (ECA13 and ECA15) a...
Storms N, Medina Torres C, Franck T, Sole Guitart A, de la Rebière G, Serteyn D.Laminitis is a pathology of the equine digit leading to a failure of the dermo-epidermal interface. Neutrophil activation is recognized as a major factor in SIRS-associated laminitis. Less is known about the role of neutrophil activation in laminitis associated with metabolic disorders. The aim of this descriptive study was to observe whether myeloperoxidase is increased in the laminae during early stage laminitis in three horses subjected to a prolonged euglycemic hyperinsulinemic clamp (pEHC). After 48 h of pEHC-treatment, horses were subjected to euthanasia. Two healthy horses are used as c...
Delvescovo B.This article describes the most common causes of urine discoloration. The review includes a description of the most common disorders causing hematuria, highlighting clinical presentation, treatments, and pathophysiology. Causes of hemoglobinuria and myoglobinuria together with their mechanisms of renal injury are also reviewed.
Kjeldsen ST, Nissen SD, Buhl R, Hopster-Iversen C.Atrial fibrillation (AF) is the most common arrhythmia in horses causing poor performance. As in humans, the condition can be intermittent in nature, known as paroxysmal atrial fibrillation (pAF). This review covers the literature relating to pAF in horses and includes references to the human literature to compare pathophysiology, clinical presentation, diagnostic tools and treatment. The arrhythmia is diagnosed by auscultation and electrocardiography (ECG), and clinical signs can vary from sudden loss of racing performance to reduced fitness or no signs at all. If left untreated, pAF may prom...
Mullen KR.This article overviews metabolic disorders associated with renal disease. Included is a discussion of the pathophysiology, clinical signs, and treatment of hyperchloremic metabolic acidosis associated with renal tubular acidosis. Conditions affecting the central nervous system including uremic encephalopathy and hyponatremic encephalopathy secondary to renal disease are presented. Finally, a discussion of the unique features of calcium and phosphorus homeostasis in horses is provided with special emphasis on a recently described syndrome of calcinosis and calciphylaxis of unknown etiology.
Divers TJ.Regulation of renal blood flow is by both extrinsic and intrinsic systems. Intrinsic regulation occurs via the afferent and efferent arterioles and tubuloglomerular feedback mechanisms with activation of the juxtaglomerular apparatus. Mechanisms of acute kidney injury are frequently associated with changes in renal blood flow. Acute tubular necrosis and apoptosis are common in horses following ischemic or toxic insults and in sepsis-associated acute kidney injury. Sepsis-associated renal injury often has a complex mechanism of disease involving both functional and obstructive changes in intrar...
José Antonio G, Jim S, Ramés SJ, Rohrbach BW, Alejandro Rodríguez M, Laura Romero R, Robert D.To examine changes occurring in normal pelvic suspensory ligaments (SLs) of horses after denervating these ligaments and to investigate the effect chronic inflammation might have on these changes. Methods: 10 horses. Methods: The SL of 1 randomly selected pelvic limb of each of 5 horses was injected with collagenase to induce desmitis, and 42 days later, the proximal aspect of both pelvic SLs were denervated. The SLs were harvested 120 days after being denervated, and the morphological and histological characteristics of each collagenase-injected, denervated SL were compared with those of the ...
Tesena P, Kingkaw A, Phaonakrop N, Roytrakul S, Limudomporn P, Vongsangnak W, Kovitvadhi A.Equine melanocytic neoplasm (EMN) is a common disease in older grey horses. The purpose of this study was to examine the potential proteins throughout EMN stages from faecal proteomic outlining using functional analysis. Faecal samples were collected from the rectum of 25 grey horses divided into three groups; normal group without EMN ( = 10), mild EMN ( = 6) and severe EMN ( = 9). Based on the results, 5910 annotated proteins out of 8509 total proteins were assessed from proteomic profiling. We observed differentially expressed proteins (DEPs) between the normal group and the EMN group, and 1...
Whitty JA, Miller AV, Miller AD, Carney PC, Scrivani PV.The styloid process sheath (SPS) is a part of the tympanic temporal bone and an incomplete bony sleeve surrounding the styloid process, tympanohyoid cartilage, and dorsal part of the stylohyoid bone. In horses undergoing head CT, we observed a range of SPS sizes and questioned whether differences were early features of temporohyoid osteoarthropathy (THO) or normal anatomic variations associated with age, body weight, sex, or breed. We hypothesized that SPS sizes were positively correlated with age and body weight, but not with sex or breed. Using a convenience population of horses that underwe...
Mainguy-Seers S, Diaw M, Lavoie JP.While the prevalence of asthma is higher in boys than in girls during childhood, this tendency reverses at puberty, suggesting an effect of sex hormones on the disease pathophysiology. Fluctuations of asthma severity concurring with the estrus cycle are reported in women, but this phenomenon has never been investigated in mares to date. The objective of this exploratory study was to determine whether the estrus cycle modulates airway obstruction in severe equine asthma (SEA). Five mares with SEA during exacerbation of the disease were studied. The whole breath, expiratory and inspiratory resis...
Robles M, Loux S, de Mestre AM, Chavatte-Palmer P.Equine placental development is a long process with unique features. Implantation occurs around 40 days of gestation (dpo) with the presence of a transient invasive placenta from 25-35 to 100-120 dpo. The definitive, non-invasive placenta remains until term (330 days). This definitive placenta is diffuse and epitheliochorial, exchanging nutrients, gas and waste with the endometrium through microvilli, called microcotyledons. These are lined by an external layer of haemotrophic trophoblast. Moreover, histotrophic exchange remains active through the histotrophic trophoblast located along the are...
Tucker ML, Wilson DG, Reinink SK, Carmalt JL.To characterize the 3-D geometry of the equine larynx replicating laryngeal hemiplegia and 4 surgical interventions by use of CT under steady-state airflow conditions. Secondly, to use fluid mechanic principles of flow through a constriction to establish the relationship between measured airflow geometries with impedance for each surgical procedure. Methods: 10 cadaveric horse larynges. Methods: While CT scans were performed, inhalation during exercise conditions was replicated for each of the following 5 conditions: laryngeal hemiplegia, left laryngoplasty with ventriculocordectomy, left lary...
Roth P, Stanley J, Chamoun-Emanuelli A, Whitfield-Cargile C, Coleman M.To compare the inflammatory response of murine macrophages exposed to the enteric microbiome of obese horses versus nonobese horses. Methods: Fecal samples from 12 obese horses (body condition score ≥ 7/9) and 12 nonobese horses (body condition score 4 to 5/9) with similar dietary management. Methods: Fecal supernatant was prepared from frozen fecal samples. RAW 264.7 macrophage cells were exposed to the fecal extract. Inflammatory cytokine (interleukin-1β, tumor necrosis factor-α, and interleukin-6) gene expression was quantified via real-time quantitative reverse transcription PCR assay,...
Hurcombe SDA, Radcliffe RM, Cook VL, Divers TJ.Hemorrhagic shock in horses may be classified in several ways. Hemorrhage may be considered internal versus external, controlled or uncontrolled, or described based on the severity of hypovolemic shock the patient is experiencing. Regardless of the cause, as the severity of hemorrhage worsens, homeostatic responses are stimulated to ameliorate the systemic and local effects of an oxygen debt. In mild to moderate cases of hemorrhage (<15% blood volume loss), physiological adaptations in the patient may not be clinically apparent. As hemorrhage worsens, often in the uncontrolled situation suc...
Minamijima Y, Tozaki T, Kuroda T, Urayama S, Nomura M, Yamamoto K.Equine colitis is a diarrhoeal disease caused by inflammation of the large bowel and can potentially be life-threatening due to its rapid progression. Pathogenesis is multifactorial and pathophysiology is highly complicated, therefore, reliable diagnostic biomarkers are needed in the veterinary field. Objective: Serum is one of the most commonly used diagnostic tools in equine clinical investigation. To discover diagnostic or prognostic protein markers for colitis in horse serum, comprehensive and comparative proteomic analysis was conducted using liquid chromatography-tandem mass spectrometry...
Merlin A, Ravinet N, Sévin C, Bernez-Romand M, Petry S, Delerue M, Briot L, Chauvin A, Tapprest J, Hébert L.Cyathostomins are considered as the most prevalent and pathogenic parasites of grazing horses. The development on pastures of the free-living stages of these gastrointestinal worms is particularly influenced by outdoor temperature. Understanding the bionomics of free-living stages is an important prerequisite to implement mathematical models designed to assess the parasitic risk for grazing equids. The aim of this study was to assess the effect of 3 constant temperatures under laboratory conditions (10 ± 1 °C, 23 ± 2 °C, 30 ± 2 °C) and one fluctuating temperature under outdoor c...
Norton NM, Santschi E, Fischer KJ.The etiology of subchondral bone cysts (SBCs) is not fully understood. Mechanical trauma and fluid pressure are two mechanisms believed to cause their formation and growth. The equine stifle joint provides a natural animal model for studying SBCs. Computed tomography images of an extended yearling cadaveric stifle joint were segmented using ScanIP to isolate bones and relevant soft tissues. Three model geometries were created to simulate cyst sizes of approximately 0.03 cm (C1), 0.5 cm (C2), and 1 cm (C3). A uniform pressure resulting in 3000 N force was applied at the proximal end of the fem...
Lanier CJ, Taintor JS, Christopherson PW, Spangler EA.Acidemia in sick or injured horses is often due to lactic acid accumulation. Alterations in platelet function and hemostasis are among numerous deleterious effects caused by decreased physiologic pH. Objective: We aimed to evaluate the effect of hyperlactatemia and resultant acidemia on platelet aggregation in equine whole blood using impedance aggregometry. Methods: Platelet aggregation was measured using the Multiplate analyzer in whole blood from 34 healthy horses at baseline and after in vitro addition of lactic acid to adjust the pH. Platelet aggregation of each sample was quantified by t...
Martano M, Altamura G, Power K, Liguori P, Restucci B, Borzacchiello G, Maiolino P.It is well known that δ-bovine papillomaviruses (BPV-1, BPV-2 and BPV-13) are one of the major causative agents of equine sarcoids, the most common equine skin tumors. Different viruses, including papillomaviruses, evolved ingenious strategies to modulate autophagy, a complex process involved in degradation and recycling of old and damaged material. Methods: The aim of this study was to evaluate, by immunohistochemistry (IHC) and Western blot (WB) analysis, the expression of the main related autophagy proteins (Beclin 1, protein light chain 3 (LC3) and P62), in 35 BPV1/2 positive equine sarco...
Mönki J, Saastamoinen M, Karikoski N, Norring M, Rajamäki M, Mykkänen A.The effects of bedding material on air quality are important amongst horses worldwide. Respiratory diseases, especially equine asthma, are highly prevalent with air hygiene playing a major role on the pathophysiology of these diseases. The objective of our study was to investigate the effects of four bedding materials on the respiratory signs, tracheal mucus score, and tracheal wash (TW) and bronchoalveolar lavage fluid (BALF) cytology in healthy adult horses. The study design was a prospective controlled cross-over study, and the subjects were healthy adult riding school horses ( = 32) from a...
Doll CU, Niebert S, Burk J.Tendon lesions are common sporting injuries in humans and horses alike. The healing process of acute tendon lesions frequently results in fibrosis and chronic disease. In horses, local mesenchymal stromal cell (MSC) injection is an accepted therapeutic strategy with positive influence on acute lesions. Concerning the use of MSCs in chronic tendon disease, data are scarce but suggest less therapeutic benefit. However, it has been shown that MSCs can have a positive effect on fibrotic tissue. Therefore, we aimed to elucidate the interplay of MSCs and healthy or chronically diseased tendon matrix...
Roberts JH, Halper J.Repair and healing of injured and diseased tendons has been traditionally fraught with apprehension and difficulties, and often led to rather unsatisfactory results. The burgeoning research field of growth factors has opened new venues for treatment of tendon disorders and injuries, and possibly for treatment of disorders of the aorta and major arteries as well. Several chapters in this volume elucidate the role of transforming growth factor β (TGFß) in pathogenesis of several heritable disorders affecting soft tissues, such as aorta, cardiac valves, and tendons and ligaments. Several member...
Ryan A, Gurney M, Steinbacher R.A 10-year-old 466 kg mustang gelding presented to an equine referral hospital for surgical repair of nasal, frontal and lacrimal bone fractures from an unknown trauma. Surgical repair was performed under general anaesthesia, including a right-sided maxillary regional anaesthetic block with mepivacaine hydrochloride. Progressive hyperkalaemia was documented perianaesthetically (T-3 mins; 134 mins after induction; potassium 6.4 mmol/L (ref 3.5-5.1 mmol/L). Perianaesthetic bradycardia was attributed to alpha -2 agonist infusion administration, and other characteristic ECG changes (flattened ...
Fortin-Trahan R, Lemirre T, Santschi EM, Janes JG, Richard H, Fogarty U, Beauchamp G, Girard CA, Laverty S.There is a knowledge gap about how equine MFC subchondral radiolucencies (SR) arise and evolve. Osteoclasts are believed to have a role but have not been studied in situ. Objective: To measure and compare osteoclast density and the percentage of chondroclasts in healthy and MFC SR specimens from juvenile Thoroughbreds. Methods: Cadaveric study. Methods: Medial femoral condyles (MFC) from a tissue bank of equine stifles were studied. Inclusion criteria were MFCs (≤8 months old) with a computed tomography SR lesion and histological focal failure of endochondral ossification (L group). Contral...
Luethy D.Treatment of equine laminitis continues to be a challenge despite recent advancements in knowledge of the pathophysiology of laminitis. With more evidence supporting its use, distal limb hypothermia or cryotherapy has become a standard of care for both prevention of laminitis and treatment of the early stages of acute laminitis. Recent studies have demonstrated that cryotherapy reduces the severity of sepsis-related laminitis and hyperinsulinemic laminitis in experimental models and reduces the incidence of laminitis in clinical colitis cases. This article reviews the recent literature support...
McFarlane D.Parkinson's disease (PD) is a leading cause of neurologic disability in the aged population. Remarkable progress has been made in the past decade to understand the cellular and molecular events that occur in PD. However attempts to unravel the early, initiating factors in the pathogenesis of dopaminergic neurodegeneration and PD have been limited by the lack of a suitable animal model. Models in which there has been genetic or environmental manipulation are not of use in determining the natural cause of a disease. While a large scale prospective human study would be ideal, the relatively low p...
Johnson PJ.Cutaneous neoplasia represents a clinical problem with which veterinarians are commonly challenged. This article addresses equine cutaneous squamous cell carcinoma, squamous cell papilloma, melanoma, mastocytosis, and lymphosarcoma. Current concepts regarding the origin, pathogenesis, diagnosis and treatment of each neoplasm is emphasized.
Schott HC.PPID in older equids has become a major health concern of horse owners. In response, equine practitioners have made greater efforts at understanding, diagnosing, and treating this disorder. Although PPID is recognized to be a different form of pituitary-dependent hyperadrenocorticism than is seen in canine or human patients, relatively little is known about the pathophysiology and natural progression of the disease. At present, the diagnosis is best supported by manifestation of characteristic clinical signs and endocrinologic test results, preferably a supportive DST result. Treatment must fo...
Malekipour F, Whitton C, Oetomo D, Lee PV.Despite the important role of subchondral bone in maintaining the integrity of the overlying articular cartilage, little research has focused on measuring its mechanical behavior, particularly under injurious load conditions such as impact compression. In this study, the stiffness and the absorbed energy of subchondral bone were compared to that of its overlying cartilage by applying impact compression to equine cartilage-bone specimens. Deformations of the cartilage and subchondral bone were examined independently within the cartilage-bone unit by analyzing real-time images of cartilage-bone ...
Svala E, Jin C, Rüetschi U, Ekman S, Lindahl A, Karlsson NG, Skiöldebrand E.The glycoprotein lubricin contributes to the boundary lubrication of the articular cartilage surface. The early events of osteoarthritis involve the superficial layer where lubricin is synthesised. Objective: To characterise the glycosylation profile of lubricin in synovial fluid from horses with osteoarthritis and study secretion and degradation of lubricin in an in vitro inflammation cartilage model. Methods: In vitro study. Methods: Synovial fluid samples collected from horses with joints with normal articular cartilage and structural osteoarthritic lesions; with and without osteochondral f...
Tung JT, Arnold CE, Alexander LH, Yuzbasiyan-Gurkan V, Venta PJ, Richardson DW, Caron JP.To determine the effects of prostaglandin E2 (PGE2) on recombinant equine interleukin (IL)-1beta-stimulated expression of matrix metalloproteinases (MMP 1, MMP 3, MMP 13) and tissue inhibitor of matrix metalloproteinase 1 (TIMP 1) in vitro. Methods: Cultured equine chondrocytes. Methods: Stationary monolayers of first-passage chondrocytes were exposed to graduated concentrations of PGE2 with or without a subsaturating dose (50 pg/ml) of recombinant equine IL-1beta (reIL-1beta) to induce expression of MMP 1, MMP 3, MMP 13, and TIMP 1, followed by RNA isolation and northern blotting. In subseque...
Davis MS, Williams CC, Meinkoth JH, Malayer JR, Royer CM, Williamson KK, McKenzie EC.To determine effects of exercise performed while breathing cold air on expression of cytokines and influx of neutrophils in airways of horses. Methods: 9 adult horses. Methods: In a crossover study, bronchoalveolar lavage fluid (BALF) was obtained 24 and 48 hours after each of 2 submaximal exercise sessions performed by horses while breathing warm (25 degrees C) or cold (-5 degrees C) air. Total and differential nucleated cell counts were determined for each BALF sample. Relative mRNA expression of cytokines in BALF cells was quantified by use of a reverse transcription-PCR assay. Results: Hor...
Meyers S, Bulkeley E, Foutouhi A.The biological nature of age-related declines in fertility in males of any species, including stallions, has been elusive. In horses, the economic costs to the breeding industry are frequently extensive. Mitochondrial function in ejaculated sperm, which is essential for sperm motility, is reflected by adenosine triphosphate production, mitochondrial oxidative efficiency and production of reactive oxygen species, and that this balance may become compromised in ageing stallions and during the process of cryopreservation. This presentation will focus on mitochondrial integrity and function as an ...
Marshall JF, Blikslager AT.Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used in the management of pain and endotoxaemia associated with colic in the horse. While NSAIDs effectively treat the symptoms of colic, there is evidence to suggest that their administration is associated with adverse gastrointestinal effects including right dorsal colitis and inhibition of mucosal barrier healing. Several studies have examined the pathophysiology of NSAID associated effects on the large and small intestine in an effort to avoid these complications and identify effective alternative medications. Differences in the re...
Pihl TH, Andersen PH, Kjelgaard-Hansen M, Mørck NB, Jacobsen S.Peritoneal fluid (PF) analysis is a valuable diagnostic tool in equine medicine. Markers such as serum amyloid A (SAA) and haptoglobin (Hp) could facilitate the diagnosis of inflammatory abdominal conditions. Objective: The objectives were to (1) establish reference intervals (RI) for SAA and Hp in serum and PF in healthy horses, (2) compare SAA and Hp concentrations between healthy horses and horses with colic, and (3) to assess the correlation between serum and PF concentrations. Methods: Serum amyloid A and Hp concentrations were determined by automated assays in prospectively enrolled heal...
Mellor DJ, Beausoleil NJ.Horses engaged in strenuous exercise display physiological responses that approach the upper functional limits of key organ systems, in particular their cardiorespiratory systems. Maximum athletic performance is therefore vulnerable to factors that diminish these functional capacities, and such impairment might also lead to horses experiencing unpleasant respiratory sensations, i.e., breathlessness. The aim of this review is to use existing literature on equine cardiorespiratory physiology and athletic performance to evaluate the potential for various types of breathlessness to occur in exerci...
Oreff GL, Fenu M, Vogl C, Ribitsch I, Jenner F.For research on tendon injury, many different animal models are utilized; however, the extent to which these species simulate the clinical condition and disease pathophysiology has not yet been critically evaluated. Considering the importance of inflammation in tendon disease, this study compared the cellular and molecular features of inflammation in tenocytes of humans and four common model species (mouse, rat, sheep, and horse). While mouse and rat tenocytes most closely equalled human tenocytes' low proliferation capacity and the negligible effect of inflammation on proliferation, the wound...
Gold JR, Divers TJ, Barton MH, Lamb SV, Place NJ, Mohammed HO, Bain FT.Little information exists on the hypothalamic-pituitary-adrenal axis in septic foals. Objective: The plasma concentrations of adrenocorticotropin (ACTH) and cortisol are expected to be higher in septic foals as compared to normal foals. The concentrations of hormones in septic foals also are expected to differ further depending upon survival. Methods: Twenty-eight control foals and 46 septic foals 11 or a positive blood culture. The control foals were age matched to the septic foals in the study. ACTH and cortisol concentrations were measured by a chemiluminescent immunoassay system. Results: ...
Tew SR, McDermott BT, Fentem RB, Peffers MJ, Clegg PD.Messenger RNA (mRNA) decay rates control not only gene expression levels, but also responsiveness to altered transcriptional input. We undertook this study to examine transcriptome-wide posttranscriptional regulation in both normal and osteoarthritic (OA) human articular chondrocytes. Methods: Human articular chondrocytes were isolated from normal or OA tissue. Equine articular chondrocytes were isolated from young or old horses at a commercial abattoir. RNA decay was measured across the transcriptome in human cells by microarray analysis following an actinomycin D chase. Messenger RNA levels ...
Theegarten D, Sachse K, Mentrup B, Fey K, Hotzel H, Anhenn O.Recurrent airway obstruction (RAO) in horses is a naturally occurring dust-induced disease mainly characterized by bronchiolitis which shows histological and pathophysiological similarities to human chronic obstructive pulmonary disease (COPD). In human COPD previous investigations indicated an association with Chlamydophila psittaci infection. The present study was designed (1) to clarify a possible role of this infectious agent in RAO and (2) to investigate the suitability of this equine disorder as a model for human COPD. Methods: Clinico-pathological parameters of a total of 45 horses (25 ...
Hoffman AM, Mazan MR, Ellenberg S.To correlate indices of airway reactivity to bronchoalveolar lavage (BAL) fluid cytologic features in horses with a recent decline in exercise tolerance. Methods: 20 actively working horses from 2 to 24 years old. Methods: Bronchoalveolar lavage fluid samples were obtained and analyzed. Forced oscillatory mechanics (1-7 Hz) technique was used for measurements of total respiratory system resistance (RRS), compliance (CRS), and resonant frequency (fres). Changes in RRS (1 Hz) during histamine challenge were used to generate histamine dose-response curves, from which the provocative concentration...
Linz D, Hesselkilde E, Kutieleh R, Jespersen T, Buhl R, Sanders P.Atrial fibrillation is triggered by the pulmonary veins in humans. Although atrial fibrillation is known to occur in other species, the mechanisms of disease in these are not known. Here we present evidence for pulmonary vein triggers in the horse, where 3D HD Grid mapping was undertaken in the conscious state in the absence of fluoroscopy.
Lacombe VA.Glucose uptake is the rate-limiting step in glucose utilization in mammalians and is tightly regulated by a family of specialized proteins, called the facilitated glucose transporters (GLUTs/SLC2). GLUT4, the major isoform in insulin-responsive tissue, translocates from an intracellular pool to the cell surface and as such determines insulin-stimulated glucose uptake. However, despite intensive research over 50 years, the insulin-dependent and -independent pathways that mediate GLUT4 translocation are not fully elucidated in any species. Insulin resistance (IR) is one of the hallmarks of equin...
Mönki J, Hewetson M, Virtala AM.Equine gastric glandular disease (EGGD) is a term used to classify erosive and ulcerative diseases of the glandular mucosa of the equine stomach. Epidemiologic studies of risk factors for EGGD have not been reported. Objective: To determine risk factors for EGGD. Methods: Cases (n = 83) had endoscopic evidence of EGGD; controls (n = 34) included healthy horses and horses with equine squamous gastric disease (ESGD) without EGGD. Methods: Retrospective case-control study. The data were analyzed by multivariable logistic regression modeling. Analysis was performed on the full dataset. An addi...
Hennemann S, de Abreu MR.Degenerative lumbar spinal stenosis is the most frequent cause of low back pain and/or sciatica in the elderly patient. Epidemiology, pathophysiology, clinical manifestations and testing are reviewed in a wide current bibliographic investigation. The importance of the relationship between clinical presentation and imaging study, especially magnetic resonance imaging (MRI), is emphasized. Prior to treatment indication, it is necessary to identify the precise location of pain, as well as the differential diagnosis between neurological and vascular lameness. Conservative treatment combining medic...
Scheidegger MD, Gerber V, Bruckmaier RM, van der Kolk JH, Burger D, Ramseyer A.This study tested the hypothesis that adrenocortical function would be altered in horses with equine gastric ulcer syndrome (EGUS). Twenty-six sport horses competing at national or international levels in eventing (n=15) or endurance (n=11) were subjected to a gastroscopic examination and an adrenocorticotropic hormone (ACTH) stimulation test. Salivary cortisol concentrations were measured before (baseline) and after (30, 60, 90, 120 and 150min) IV ACTH injection (1μg/kg bodyweight). Within EGUS, two distinct diseases, equine squamous gastric disease (ESGD) and equine glandular gastric diseas...
Gilger BC, Michau TM.Equine recurrent uveitis (ERU) is one of the most common causes of blindness in horses. Until recently, treatment of this condition consisted only of symptomatic therapy, typically with steroidal and nonsteroidal medications. A better understanding of the disease process(es) has permitted new medical and surgical therapies that have recently been described. This article highlights clinical features of ERU, the causes of ERU, and new management and treatment options for horses with ERU.
Naccache F, Metzger J, Distl O.Osteochondrosis (OC) is an injury to cartilage canals with a following necrosis in the growth cartilage, from there it can develop to osteochondrosis dissecans (OCD). Due to its high impact in the equine industry, new insights into predisposing factors and potential high-risk genetic variants are warranted. This article reviews advancements in quantitative and molecular genetics in refining estimation of genetic parameters and identifying predisposing genetic loci. Heritabilities were highest for hock OC with estimates at 0.29-0.46 in Hanoverian warmblood and Norwegian trotters, whereas in Tho...
Reynolds A, Keen JA, Fordham T, Morgan RA.Obesity is a common feature of equine metabolic syndrome (EMS). In other species, obese adipose tissue shows pathological features such as adipocyte hypertrophy, fibrosis, inflammation and impaired insulin signalling all of which contribute to whole body insulin dysregulation. Such adipose tissue dysfunction has not been investigated in horses. Objective: To determine if obese horses with EMS have adipose tissue dysfunction characterised by adipocyte hypertrophy, fibrosis, inflammation and altered insulin signalling. Methods: Cross-sectional post-mortem study. Methods: Samples of peri-renal (v...
Simões J, Batista M, Tilley P.Severe equine asthma is a chronic respiratory disease of adult horses, occurring when genetically susceptible individuals are exposed to environmental aeroallergens. This results in airway inflammation, mucus accumulation and bronchial constriction. Although several studies aimed at evaluating the genetic and immune pathways associated with the disease, the results reported are inconsistent. Furthermore, the complexity and heterogeneity of this disease bears great similarity to what is described for human asthma. Currently available studies identified two chromosome regions (ECA13 and ECA15) a...
Tuniyazi M, He J, Guo J, Li S, Zhang N, Hu X, Fu Y.Laminitis is a common and serve disease which caused by inflammation and pathological changes of the laminar junction. However, the pathologic mechanism remains unclear. In this study we aimed to investigate changes of the gut microbiota and metabolomics in oligofructose-induced laminitis of horses. Results: Animals submitted to treatment with oligofructose had lower fecal pH but higher lactic acid, histamine, and Lipopolysaccharide (LPS) in serum. Meanwhile, oligofructose altered composition of the hindgut bacterial community, demonstrated by increasing relative abundance of Lactobacillus and...
Hosaka Y, Kirisawa R, Yamamoto E, Ueda H, Iwai H, Takehana K.Although inflammatory activation of cytokines have been analyzed in various tissues, there have only been a few and as-yet-inconclusive studies on cytokines in equine tendons. In this study, the localizations of 4 cytokines (IL-1alpha, IL-1beta, TNFalpha and IFNgamma) in tendinocytes of the equine superficial digital flexor tendon (SDFT) were analyzed by the use of an immunohistochemical method. In inflamed tendons positive staining for all 4 cytokines antibodies were detected in endotedinieum cells and vascular epithelial cells. In contrast, negative or trace immunoreactions were obtained in ...
Stewart AJ, Hackett E, Bertin FR, Towns TJ.Plasma adrenocorticotropic hormone (ACTH) and serum cortisol concentrations increase with illness-associated stress. Dynamics of plasma ACTH and serum cortisol concentrations in adult horses with systemic illness are undocumented. Objective: To determine whether ACTH and cortisol concentrations and the ACTH/cortisol ratio vary with survival, the presence of systemic inflammatory response syndrome (SIRS), or ischemic gastrointestinal lesions at admission, or throughout hospitalization. Methods: One hundred fifty-one adult horses. Methods: Prospective study measuring serum cortisol and plasma AC...
