Inflammation is a biological response of the horse's body to harmful stimuli, such as pathogens, damaged cells, or irritants. It is a complex process that involves the activation of immune cells, the release of inflammatory mediators, and changes in blood flow. In horses, inflammation can manifest in various forms, affecting different tissues and organs, including the joints, respiratory system, and skin. The inflammatory response is an essential component of the horse's immune system, aiming to eliminate the initial cause of cell injury, clear out damaged cells and tissues, and establish tissue repair. This topic page gathers peer-reviewed research studies and scholarly articles that explore the mechanisms, effects, and management of inflammation in equine health.
Spiess BM.Equine recurrent uveitis (ERU) has always been and still is an important disease with a significant impact on the horse industry in Europe, with a prevalence of 8-10%. The need to understand and manage the disease has spurred the development of veterinary ophthalmology in general, although the aetiology of the disease remains the subject of intense discussion. It is most probably an autoimmune disease triggered, at least in Europe, in the majority of cases by Leptospira spp. The therapy of ERU has evolved over the centuries from various methods of bloodletting to rational medical therapy using...
Nell B, Walde I.Diseases of the vitreous, fundus and optic nerve are described and illustrated according to their ophthalmological appearance. Vitreal alterations are commonly of developmental, degenerative, age related, traumatic or inflammatory origin and of minor clinical relevance. In contrast, those affecting the fundus, may be accompanied by visual deficits or blindness. Fundic lesions of inflammatory (multifocal or peripapillary chorioretinitis, haemorrhage, retinal detachment) and traumatic origin have to be differentiated from congenital (congenital stationary night blindness, colobomatous defects, r...
Wilkie DA.Understanding and awareness of equine glaucoma has significantly improved in recent years. The availability of portable tonometers and veterinarian/owner awareness has increased the frequency of glaucoma as a clinical diagnosis. A variety of medications for the medical management of equine glaucoma have been evaluated and the addition of lasers has improved the surgical treatment of equine glaucoma. Despite this, equine glaucoma is an insidious and painful disease that probably remains under diagnosed and often results in blindness in the affected eye.
Leclere M, Lavoie-Lamoureux A, Gélinas-Lymburner E, David F, Martin JG, Lavoie JP.Recent studies suggest that airway smooth muscle remodeling is an early event in asthma, but whether it remains a dynamic process late in the course of the disease is unknown. Moreover, little is known about the effects of an antigenic exposure on chronically established smooth muscle remodeling. We measured the effects of antigenic exposure on airway smooth muscle in the central and peripheral airways of horses with heaves, a naturally occurring airway disease that shares similarities with chronic asthma. Heaves-affected horses (n = 6) and age-matched control horses (n = 5) were kept on pastu...
García-López JM, Jenei T, Chope K, Bubeck KA.4 horses with a history of neck pain, abnormal head carriage, and related inability to perform were examined. Cranial nuchal bursitis was diagnosed in 2 horses, and caudal nuchal bursitis was diagnosed in the other 2. Results: All 4 horses had prominent swelling in the region between the frontal bone and temporal fossa (ie, the poll) and abnormal head carriage. Ultrasonographic examination revealed fluid distention and synovial thickening of the cranial or caudal nuchal bursa in all 4 horses. Ultrasonography-guided aspiration of the affected region was performed successfully in 3 horses. Radio...
Lopes MA, Salter CE, Vandenplas ML, Berghaus R, Hurley DJ, Moore JN.To investigate the effect of ex vivo exposure to lipopolysaccharide (LPS) on the expression of inflammatory genes in leukocytes from horses with gastrointestinal (Gl) disease and determine whether the pattern or magnitude of the response to LPS correlated with the type of disease and outcome. Methods: 49 horses with Gl disease and 10 healthy horses Methods: Leukocytes were isolated from blood samples and submitted to 3 protocols: immediate freezing, freezing after 4-hour incubation in medium, and freezing after 4-hour incubation in medium containing LPS. Expression of 14 genes associated with ...
Rodriguez Hurtado I, Stewart AJ, Wolfe DF, Caldwell FJ, Harrie M, Whitley EM.Hyaluronan (HA), a glycosaminoglycan, is a major component of the pericellular matrix which envelopes mammalian cells. Binding of hyaluronan to one of its specific receptors, CD44, modulates transduction of intracellular signals which direct a variety of processes, including embryogenesis, wound healing, inflammation, and neoplasia. Since regulation of these processes is critical to equine reproductive success, localization of constitutive CD44 expression was evaluated by immunohistochemical methods in ovarian, oviductal, and uterine tissues from healthy mares. Ovarian stroma contained thecal ...
Gilger BC, Wilkie DA, Clode AB, McMullen RJ, Utter ME, Komaromy AM, Brooks DE, Salmon JH.To determine the long-term efficacy, complications, and duration of effect of a cyclosporine (CsA) suprachoroidal implant (CSI) in horses with equine recurrent uveitis (ERU). Methods: Horses with ERU were treated with a 6-mm diameter, 25 mg, reservoir matrix CsA implant in the deep sclera adjacent to the suprachoroidal space. Horses with follow-up >1 year were examined for frequency of uveitis episodes, complications, and vision at last recheck. Results: Data from 151 eyes of 133 horses from the USA and Europe that had CsA devices implanted for ERU were reviewed. Follow-up time ranged from 13 ...
Kamm JL, Nixon AJ, Witte TH.Understanding the expression of catabolic and anabolic genes during osteoarthritis progression should help to identify the major mediators of the disease. Objective: To compare the cytokine and anabolic marker concentrations in synovium, synovial fluid and cartilage between normal and osteoarthritic joints. Methods: Carpi from horses age 2-11 years were used. Tissues were harvested at the time of surgery or euthanasia, and RNA was isolated for RT-PCR analysis. Tumour necrosis factor alpha (TNFα), interleukin-1beta (IL-1β), aggrecanase 1 (ADAMTS-4), aggrecanase 2 (ADAMTS-5), matrix metallopro...
El-Deeb WM, El-Bahr SM.A total of 30 horses were divided into two groups, one served as a control whereas other was rhabdomyolysis diseased horses. After blood collection, the resulted sera were used for estimation of the activities of creatin kinase (CK), aspartate transaminase (AST), lactate dehydrogenase (LDH), lactic acid, triacylglycerol (TAG), glucose, total protein, albumin, globulin, urea, creatinine, Triiodothyronine (T(3)), calcium, sodium, potassium, phosphorus, chloride, vitamin E, interleukin-6 (IL-6) and tumor necrosis-α (TNF-α). In addition, whole blood was used for determination of selenium, reduce...
Barry S.The ability of non-steroidal anti-inflammatory drugs (NSAID) to inhibit bone healing has been established in experimental animal models using mice, rats, and rabbits. The mechanism of action is largely unknown but stems from prostaglandin inhibition and is likely multifactorial. In human medicine NSAID are known to prevent heterotopic ossification, however the clinical importance of their effects on bone healing remains controversial. Although a small handful of reports suggest that NSAID suppress bone healing in dogs and horses, there is little published information to direct veterinary pract...
Lane JK, Cohen JM, Zedler ST, Hollis AR, Southwood LL.To describe a novel surgical technique for management of right dorsal colitis in the horse. Methods: Clinical report. Methods: 14-year-old Warmblood gelding. Methods: The horse was referred for treatment of a stromal abscess and signs of right dorsal colitis. Plasma chemistry revealed marked hypoproteinemia. Abdominal ultrasonographic examination showed a thickened right dorsal colon (RDC). Medical treatment was unsuccessful. With the horse in left lateral recumbency under general anesthesia, an approach to the right side of the abdomen through a 16th rib resection was made. The thoracic cavit...
BMJ case reportsAugust 26, 2010
Volume 2010 bcr1120092444 doi: 10.1136/bcr.11.2009.2444
Thompson RN, McNicholl BP.This report describes a case of accidental needlestick injury involving a live equine vaccination, Equilis StrepE. A vet presented herself to the Emergency Department having accidentally injected herself with an equine vaccination. Her left thumb (injury site) was inflamed and had lymphangitis progressing proximally along her left arm. Her inflammatory markers were not raised. The swelling, erythma and lymphangitis had improved markedly with intravenous antibiotics. She had no sequelae at follow-up. Equilis StrepE is a vaccine for submucosal administration containing a modified live avirulent ...
McIlwraith CW.Intra-articular use of corticosteroids has become a recent focus (or re-focus) of attention in the Thoroughbred racing industry. This manuscript reviews the clinical use and scientific basis of intra-articular corticosteroid administration including catastrophic injury, articular cartilage degradation and the development of osteoarthritis (OA), as well as the timing of injection relative to racing.
van Eps A, Collins SN, Pollitt CC.Supporting limb laminitis poses a threat to all horses suffering from severe unilateral lameness. Despite its devastating effects, relatively little is known about the precise pathologic processes that lead to its development. This article reviews the potential mechanisms of supporting limb laminitis, and the authors present some preliminary data based on advanced imaging and computer-based modeling techniques aimed at further elucidating the etiology of this unique form of laminitis. Gaining a better understanding of the pathologic processes that lead to supporting limb laminitis is essential...
Kornreich B, Enyeart M, Jesty SA, Nydam DV, Divers T.Pentoxifylline (PTX) possesses a number of vasomotor, immunomodulatory, and hemorheologic properties. Based upon the hypothesis that equine laminitis and navicular disease result from microthrombosis, the inhibitory effects of PTX on inflammatory cytokines, and its inhibitory effects on human platelet aggregation, PTX has been widely used to treat equine endotoxemia, navicular disease, and laminitis. Despite this, the effects of PTX on equine platelet aggregation have not been investigated previously. Objective: PTX decreases platelet aggregation in equine whole blood at concentrations approxi...
Katavolos P, Ackerley CA, Clark ME, Bienzle D.Horses suffer from recurrent airway obstruction, an asthma-like condition induced by repeat inhalation of environmental substances present in barn air. Clara cell secretory protein (CCSP) is much reduced during active inflammation when neutrophils predominate in the airways, and in chronic asthmatics. We sought to investigate morphologic and functional interactions of CCSP with neutrophils. Bronchoalveolar and blood neutrophils from healthy control animals, and from animals with recurrent airway obstruction in remission and exacerbation, were evaluated by immuno-cytochemistry and immuno-electr...
Relave F, David F, Leclère M, Alexander K, Hélie P, Meulyzer M, Lavoie JP, Marcoux M.To validate the use of the LigaSure™ Vessel Sealing System (LVSS) to perform thoracoscopic lung tissue biopsies in heaves-affected horses. Methods: Prospective clinical study. Methods: Heaves-affected horses (n=12). Methods: Lung biopsies (n=34) were collected with the LVSS (2-4 biopsies/horse) in horses with and without clinical signs of heaves. Thoracoscope (13th intercostal space [ICS]) and 2 instruments (between the 12-15th ICS) portals were used. Selected clinical and arterial blood gas variables were monitored. Postoperative pneumothorax was evaluated. Depth of thermal injury to the su...
Lopes MA, Salter CE, Vandenplas ML, Berghaus R, Hurley DJ, Moore JN.To investigate whether expression of inflammation-associated genes in leukocytes from horses with gastrointestinal tract (GIT) diseases correlated with the type of disease and outcome. Methods: 10 healthy horses and 50 horses with GIT disease. Methods: A blood sample was collected from each healthy horse or horse with GIT disease (during admission to the hospital). Leukocytes were isolated, diluted to a standard concentration, and frozen until RNA extraction. Expression of 14 genes associated with inflammation was quantified by use of a real-time quantitative reverse transcription PCR assay. R...
Sanz MG, Sellon DC, Potter KA.A 25-year-old Appaloosa gelding was evaluated for chronic weight loss and diarrhea. A clinical diagnosis of protein loosing enteropathy was made and the gelding was euthanized. Histology revealed neoplastic lymphocytes infiltrating the mucosa of the small and large intestine. Immunohistochemistry was positive for CD3, consistent with epitheliotropic T-cell lymphoma. Lymphome T intestinal épithéliotrope primaire comme cause de diarrhée chez un cheval. Un hongre appaloosa âgé de 25 ans a été évalué pour perte de poids et diarrhée chronique. Un diagnostic clinique d’entéropathie avec...
Evans DL, Kiddell L, Smith CL.Inflammatory airway disease (IAD) is common in racehorses, and is a cause of wastage in the industry. IAD has been diagnosed by measurement of percent neutrophils (N%) in tracheal aspirates (TA). The aim of this study was to investigate whether spirometric indices of pulmonary function were correlated with N% in TAs. Limits to breathing were measured by analyses of relationships between relative times and relative respiratory gas flows during inspiration and expiration in individual breaths recorded after exercise. Horses with higher N% had significantly lower relative gas flows at the same re...
Suagee JK, Burk AO, Quinn RW, Hartsock TG, Douglass LW.Low-grade inflammation precedes the development of obesity-related metabolic disorders in humans, but whether the same is true in the horse is not known. The objective of this study was to examine the effects of weight gain and diet on the inflammatory state of horses as determined by serum concentrations of tumour necrosis factor-α (TNF), an inflammatory cytokine. Fifteen mature Thoroughbred geldings with an initial body weight (BW) of 519±12 kg and body condition score (BCS) of 4.3±0.1 were fed a diet of hay plus a concentrate that was either high in non-structural carbohydrates (NSC) (i....
Peiró JR, Barnabé PA, Cadioli FA, Cunha FQ, Lima VM, Mendonça VH, Santana AE, Malheiros EB, Perri SH, Valadão CA.The clinical efficacy of IV infusion of lidocaine for treatment of equine endotoxemia has not been studied. Objective: Lidocaine infusion after exposure to lipopolysaccharide (LPS) will inhibit the inflammatory response and have inhibitory effects on the hemodynamic and cytokine responses to endotoxemia. Methods: Twelve horses. Methods: Two equal groups (n=6): saline (GI) and lidocaine (GII). In all animals, endotoxin (500 ng/kg body weight [BW]) was injected intraperitoneally over 5 minutes. Twenty minutes later, animals received a bolus of GI or GII (1.3 mg/kg BW) over 5 minutes, followed by...
Burns TA, Geor RJ, Mudge MC, McCutcheon LJ, Hinchcliff KW, Belknap JK.Insulin resistance has been associated with risk of laminitis in horses. Genes coding for proinflammatory cytokines and chemokines are expressed more in visceral adipose tissue than in subcutaneous adipose tissue of insulin-resistant (IR) humans and rodents. Objective: To investigate adipose depot-specific cytokine and chemokine gene expression in horses and its relationship to insulin sensitivity (SI). Methods: Eleven light breed mares. Methods: Animals were classified as IR (SI=0.58+/-0.31x10(-4) L/min/mU; n=5) or insulin sensitive (IS; SI=2.59+/-1.21x10(-4) L/min/mU; n=6) based on results o...
de la Rebière de Pouyade G, Serteyn D.Despite ongoing research and a widening range of treatment options, laminitis remains a severely damaging condition with poorly understood pathophysiology. Results obtained from cytokine regulation studies during the last decade have highlighted the inflammatory nature of laminitis. This review will describe the role of systemic activation and local infiltration of neutrophils in laminar tissues in the induction of laminitis. Particular emphasis is placed on the role of neutrophil activation in subsequent vascular dysfunction and oxidative and proteolysis imbalances that are pathways previousl...
Verde C, Ferrante M, Simpson MI, Babusci M, Broglia G, Landoni MF.Twelve healthy horses were subject to the monoioidoacetate (MIA) carpitis model, which was allowed to develop for 7 days. The horses were then randomly divided into two groups. Group A (control) received an intramuscular injection of normal saline every 4 days for a total of seven injections while group B received 500 mg of a PSGAG (SYNTEX CSY36) intramuscularly every 4 days for seven treatments. Efficacy of the PSGAG was evaluated by three clinical outcomes: lameness score, carpal circumference and maximum carpal flexion. Clinical outcomes were measured on days -8 (previous to carpitis induct...
Johns IC, Del Piero F, Wilkins PA.An 11-year-old Thoroughbred broodmare was evaluated for suspected hepatic dysfunction. Clinical signs of hepatic encephalopathy were evident at admission. Hepatic ultrasonographic evaluation revealed an increase in hepatic size, rounded borders and normal echogenicity. There was no evidence of cholelithiasis or bile duct distention. Increased activity of hepatic enzymes, increased bile acid and bilirubin concentration and an increased ammonia concentration were supportive of a diagnosis of hepatic disease and hepatic encephalopathy. Histopathological evaluation of a liver biopsy specimen was c...
Verwilghen DR, Enzerink E, Martens A, Franck T, Balligand M, Henrotin Y, Detilleux J, Serteyn D.To evaluate the levels of plasmatic and synovial Coll2-1, Coll2-1NO(2) and myeloperoxidase (MPO) in horses with osteochondral lesions of the tarsocrural joint and to investigate how these levels relate to arthroscopic findings of inflammation and degeneration. Methods: Venous blood and synovial fluid samples were collected from 63 horses presented for arthroscopic removal of osteochondral fragments in the tarsocrural joint. Prior to removal of the osteochondral fragment, an exploration of the joint was performed and an inflammatory and degenerative score was determined. The blood and synovial ...
Lopes MA, Salter CE, Vandenplas ML, Berghaus R, Hurley DJ, Moore JN.To investigate whether expression of inflammation-associated genes in leukocytes from horses with gastrointestinal tract (GIT) diseases correlated with the type of disease and outcome. Methods: 10 healthy horses and 50 horses with GIT disease. Methods: A blood sample was collected from each healthy horse or horse with GIT disease (during admission to the hospital). Leukocytes were isolated, diluted to a standard concentration, and frozen until RNA extraction. Expression of 14 genes associated with inflammation was quantified by use of a real-time quantitative reverse transcription PCR assay. R...
Gardner AK, van Eps AW, Watts MR, Burns TA, Belknap JK.Supporting limb laminitis (SLL) is a devastating sequela to severe unilateral lameness in equine patients. The manifestation of SLL, which usually only affects one limb, is unpredictable and the etiology is unknown. A novel, non-painful preferential weight bearing model designed to mimic the effects of severe unilateral forelimb lameness was developed to assess lamellar signaling events in the supporting limb (SL). A custom v-shaped insert was attached to the shoe of one forelimb to prevent normal weight bearing and redistribute weight onto the SL. Testing of the insert using a custom scale pl...
Morello S, Southwood LL, Engiles J, Slack J, Crack A, Springate CM.To evaluate the effect of PERIDAN™ Concentrate on clinical findings, infection, and tissue healing in adult horses undergoing celiotomy and jejunojejunostomy. Methods: Block randomized blinded experimental in vivo study. Methods: Adult horses (n = 12). Methods: Horses had jejunojejunostomy at 2 sites and were administered 5 L of diluted PERIDAN™ Concentrate (6 horses) or Lactated Ringer's Injection (LRS) control intraperitoneally (6 horses) before body wall closure. Postoperative monitoring comprised physical examinations, serial hematology, coagulation and chemistry panels, and ultrasonog...
Söderroos D, Ignell R, Haubro Andersen P, Bergvall K, Riihimäki M.Insect bite hypersensitivity (IBH) associated with biting midges is a common allergic skin disease in horses, reducing the welfare of affected horses. This study investigated the effect of IBH on animal welfare and behaviour and assessed a new prophylactic insect repellent. In total, 30 horses were recruited for a prospective cross-over and case-control study. Clinical signs of IBH, inflammatory markers in skin biopsies and behavioural data (direct observations, motion index) were scored longitudinally during two consecutive summers. No differences were observed in the total number of itching...
Schwab U, Caldwell S, Matychak MB, Felippe J.We developed a 3-D equine bronchial epithelial cell (BEC) culture that fully differentiates into ciliary beating and mucus producing cells. Using this system, we evaluated how mucus affects the phagocytic activity of macrophages. Adult horse monocyte-derived macrophages were incubated with Rhodococcus equi for 4h either in the mucus layer of in vitro generated airway epithelium or on collagen coated membranes. Using light and electron microscopy, we noted that the number of macrophages with intracellular bacteria, and the number of intracellular bacteria per macrophage were lower in the presen...
Morini M, Gobbo F, Rinnovati R, Romagnoli N, Peli A, Massarenti C, Spadari A, Pietra M.Equine asthma is a common respiratory disease that may affect horses of any age. The diagnosis of severe equine asthma (SEA) (historically referred as recurrent airway obstruction or RAO) is based mainly on the history of the animal and clinical signs, which are further supported by the cytological examination of the bronchoalveolar lavage (BAL). This can also be helpful in monitoring the inflammation of the lower airways in response to environmental management and medication. The cytocentrifugated preparation is usually considered the method of choice for BAL cytological interpretation. The a...
Kuhn M, Guschlbauer M, Feige K, Schluesener M, Bester K, Beyerbach M, Breves G.Equine typholocolitis is a sporadic diarrheal disease causing high mortality rates. One of the risk factors responsible for this is the oral application of the macrolide antibiotic erythromycin. The aim of the present in vitro study was to investigate whether erythromycin in combination with feed restriction provokes changes in microbial hindgut metabolism and could therefore be involved in the pathogenesis of equine typhlocolitis. As application of erythromycin and feed restriction are risk factors for equine typhlocolitis, both factors were chosen to investigate their individual and combined...
French DD, Klei TM, Foil CS, Miller RI, Foil LD, Chapman MR, McClure JJ.The efficacy of a single dose of ivermectin (0.2 mg/kg), in injectable or paste formulations, against microfilariae of Onchocerca cervicalis and associated skin lesions was evaluated in 20 naturally infected horses during midsummer months in Louisiana. All horses had clinical signs of dermatitis of the ventral midline and/or limbs, shoulders, thorax, and withers. Efficacy was monitored at 21, 42, and 63 days after treatment. Procedures done at these intervals included microfilarial counts of 6-mm skin biopsy specimens of affected ventral midline, grading of gross lesions, and photography and h...
Kutscha J, Sutton DG, Preston T, Guthrie AJ.Imidocarb dipropionate is the drug of choice for equine piroplasmosis but its administration causes severe colic and diarrhoea. An imidocarb protocol that reduces these effects is needed. Objective: 1) Quantification of the effects of imidocarb dipropionate on equine orocaecal transit time (OCTT), with and without atropine or glycopyrrolate premedication and 2) investigation of an improved pretreatment regimen for imidocarb administration. Objective: Treatment with imidocarb dipropionate will result in colic and reduced OCTT as demonstrated by the lactose 13C-ureide breath test which will be a...
Marzahl C, Hill J, Stayt J, Bienzle D, Welker L, Wilm F, Voigt J, Aubreville M, Maier A, Klopfleisch R, Breininger K, Bertram CA.Pulmonary hemorrhage (P-Hem) occurs among multiple species and can have various causes. Cytology of bronchoalveolar lavage fluid (BALF) using a 5-tier scoring system of alveolar macrophages based on their hemosiderin content is considered the most sensitive diagnostic method. We introduce a novel, fully annotated multi-species P-Hem dataset, which consists of 74 cytology whole slide images (WSIs) with equine, feline and human samples. To create this high-quality and high-quantity dataset, we developed an annotation pipeline combining human expertise with deep learning and data visualisation te...
Gröndahl G, Johannisson A, Jensen-Waern M.The ability of equine plasma from different donors to enhance phagocytic capacity was assessed in neutrophils obtained from seven foals, aged 7-8 days (Study A), and from seven adult horses (Study B). Neutrophils were allowed to phagocytize fluorescent yeast cells opsonized with plasma from one of three donors or with pooled serum, all previously frozen (-18 degrees C) and thawed. The results were analysed by flow cytometry. In study A, fresh autologous foal serum was also used for opsonization, and in study B, heat-inactivated plasma and pooled serum were used in addition to untreated samples...
Higgins AJ, Lees P.The presence of cyclooxygenase products of arachidonic acid metabolism in carrageenin-induced inflammatory exudate was investigated in ponies using two models. In the first model, an inflammatory response was stimulated by injecting carrageenin into subcutaneously implanted polypropylene tissue cages and exudates were collected at five predetermined times between 3 and 48 h. In the second model, exudates were harvested at 6, 12 and 24 h from carrageenin-impregnated polyester sponges which had also been inserted beneath the skin. Prostaglandin (PG) E2, thromboxane (TX) B2 and the stable breakdo...
Jarvis N, McKenzie HC.Weight loss occurs when the supply of energy is insufficient to meet the energy needs of an individual. The energy supply may be reduced by inadequate provision of feed, inadequate consumption, reduced digestion and absorption, or disruption in metabolic processing. Increased energy expenditure occurs with exercise and during cold temperatures, pregnancy, and lactation. Underlying clinical disease, particularly chronic inflammation, neoplasia, and protein-losing conditions, can cause weight loss or exacerbate existing weight loss. A methodical approach to weight-loss investigation and treatmen...
Bauck AG, Vidyasagar S, Freeman DE.To examine bicarbonate (HCO3-) secretion ex vivo in the equine large colon to determine any differences between the right dorsal colon (RDC) and right ventral colon (RVC). The effect of phenylbutazone (PBZ) on HCO3- secretion was examined in the RDC. Methods: 14 healthy horses. Methods: In anesthetized horses (n = 10), segments of mucosa from RDC and RVC were harvested to measure HCO3- secretion ex vivo with the pH Stat method. The effect of PBZ on HCO3- secretion in the RDC was studied in 4 additional horses. Results: Three distinct mechanisms of HCO3- secretion previously described in a muri...
Panzani S, Villani M, McGladdery A, Magri M, Kindahl H, Galeati G, Martino PA, Veronesi MC.Information regarding the plasma hormone profiles of prostaglandins (PGs), cortisol (C), and progesterone (P4) during pathologic processes in newborn foals is scarce. The aim of this study was to determine the plasma concentrations of these hormones in diseased foals (n=40) and healthy at-term foals (n=24) (Equus caballus) during the first 2 weeks of life. Blood samples were collected daily, before any treatment with nonsteroidal drugs in diseased foals, and plasma was analyzed by radioimmunoassay. 15-Ketodihydro-PGF(2alpha) (PGM) was consistently higher in diseased foals than in healthy foals...
Tsuzuki N, Kanbayashi Y, Kusano K.Arthritis is thought to cause oxidative stress in synovial fluid in humans, but there have been few reports in horses. To evaluate oxidative stress in synovial fluid in horses, this study used 19 horses with unilateral fracture of the carpal joint bone. Synovial fluid was collected from the carpal joint on the fracture (arthritis group) and contralateral (control group) sides. Diacron-reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) were then measured, and the oxidative stress index (OSI) was calculated. d-ROMs and OSI of the arthritis group were significantly hi...
McElroy A, Klinge PM, Sledge D, Donahue JE, Glabman RA, Rashmir A.The objectives of this study were to describe the anatomy, histology, and ultrastructure of the equine filum terminale (FT) and to describe the FT in hereditary equine regional dermal asthenia (HERDA), a model of human Ehlers-Danlos syndromes (EDS). Those humans suffer from tethered cord syndrome (TCS) caused by an abnormally structured FT wherein its attachment at the base of the vertebral column leads to long-term stretch-induced injury to the spinal cord. The pathophysiology of TCS in EDS is poorly understood, and there is a need for an animal model of the condition. Histopathologic and ult...
Gilger BC.This review, which is part of the "Currents in One Health" series, describes the importance of the study of immune-mediated ocular disease in the development of innovative therapeutics, such as cell and gene therapy for the eye. Recent examples of cell and gene therapy studies from the author's laboratory are reviewed to emphasize the importance of One Health initiatives in developing innovative therapies for ocular diseases. Spontaneous immune-mediated corneal disease is common in horses, cats, dogs, and humans. Autologous bone marrow-derived mesenchymal stem cells (BM-MSCs) injected subconju...
Keller LE, Tait Wojno ED, Begum L, Fortier LA.Infiltration of cluster of differentiation (CD) 3 (CD3) T cells into the synovium and synovial fluid occurs in most patients with posttraumatic osteoarthritis. During disease progression, proinflammatory T helper 17 cells and anti-inflammatory regulatory T cells infiltrate the joint in response to inflammation. This study aimed to characterize the dynamics of regulatory T and T helper 17 cell populations in synovial fluid from equine clinical patients with posttraumatic osteoarthritis to determine whether phenotype and function are associated with potential immunotherapeutic targets. An imbala...
Frean SP, Cambridge H, Lees P.The concentration-effect relationships of phenylbutazone, indomethacin, betamethasone, pentosan polysulphate (PPS) and polysulphated glycosaminoglycan (PSGAG), on proteoglycan synthesis by equine cultured chondrocytes grown in monolayers, and articular cartilage explants were measured. The effect of PSGAG on interleukin-1beta induced suppression of proteogycan synthesis was also investigated. Proteoglycan synthesis was measured by scintillation assay of radiolabelled sulphate (35SO4) incorporation. Polysulphated glycosaminoglycan and PPS stimulated proteoglycan synthesis in chondrocyte monolay...
Starzonek J, Roscher K, Blüher M, Blaue D, Schedlbauer C, Hirz M, Raila J, Vervuert I.In horses and ponies numerous medical conditions are known to be linked with inflammation in different tissues, especially in the liver. Besides affecting other metabolic pathways such as the expression of certain interleukins (IL), inflammation is associated with stress of the endoplasmic reticulum (ER). In particular, ER stress leads to adaptive stress response and can be measured by several markers of inflammatory and stress signalling pathways, like nuclear factor κB (NF-kB). Objective: To investigate lipopolysaccharide (LPS)-induced inflammatory reactions and their modulation in horses a...
Winder NC, von Fellenberg R.The peroxidase anti-peroxidase technique was used to demonstrate free and intracellular immunoglobulin (Ig) within the lungs of 23 horses with chronic small airway disease. Histologically, all the horses had chronic bronchiolitis; however, the lesions varied in degree from mild in eight horses, to moderate in nine horses and severe in six horses. Lungs from three horses which had no gross or histopathological lesions were used as controls. In comparison with control horses, horses with mild chronic bronchiolitis had increased numbers of Ig A-containing and non-immunoglobulin staining cells aro...
Olszewski MA, Robinson NE, Zhu FX, Zhang XY, Tithof PK.Neutrophilic inflammation in small airways (SA) and bronchospasm mediated via muscarinic receptors are features of chronic obstructive pulmonary disease in horses (COPD). Histamine, serotonin, and leukotrienes (LTs) are reported to be involved in the exacerbation of COPD, and currently, histamine has been shown to increase tension response to electrical field simulation (EFS) in equine SA. We tested the effects of these mediators and the effects of activated neutrophils on the cholinergic responses in SA. Histamine, serotonin, and LTD4 had a synergistic effect on EFS responses and only an addi...
Mellish MA, Lucas ZN, Puchalski SM, Kusch TA.Laminitis is a painful condition that causes lameness in horses. However, monitoring this condition in feral horses is logistically difficult. Laminitis can be detected postmortem, as inflammation of the sensitive laminae of the hoof changes the relative location of the bony structures within the hoof capsule. Thus, evaluation of cadavers may be used to estimate laminitis prevalence in feral populations of horses. The objective of this study was to estimate the prevalence of laminitis in feral horses inhabiting the Sable Island National Park Reserve, Canada, using radiographic imagery on the h...
Grosche A, Morton AJ, Graham AS, Valentine JF, Abbott JR, Polyak MM, Freeman DE.Intestinal ischaemia and reperfusion (I/R) can activate inflammatory cells in the equine colon, although effects on different types of inflammatory cells have received little attention. Objective: To assess early mucosal injury, the reaction of mucosal neutrophils, eosinophils, mast cells and macrophages, and cyclooxygenase (COX)-1 and -2 expression in response to I/R in the equine large colon. Methods: Large colon ischaemia was induced for 1 h (1hI) followed by 4 h of reperfusion in 6 horses, and mucosal biopsies were sampled before and after ischaemia, and after 1, 2 and 4 h of reperfusion. ...
Leitch M.Angular limb deformities are not uncommon in foals. Mild angular deviation due to laxity of supporting soft tissues often resolves spontaneously. However, external splinting or casting may be needed in severe cases or in those that do not resolve. When incomplete ossification of carpal or tarsal bones is the cause of the limb deformity, external support is mandatory to prevent further deformation and abnormal development of the bones. When epiphyseal and metaphyseal abnormalities cause axial deviation, surgical intervention is usually necessary. Circumferential periosteal transection and/or tr...
Barton MH, Moore JN.Whole blood from 10 healthy horses was aseptically collected into heparin or citrate anticoagulant and incubated in vitro for 6 hr in the absence (saline control) or presence of 1 ng endotoxin/ml blood. Pentoxifylline (0.1, 1, 10, or 100 micrograms/ml blood) was added 1 hr before, at the same time, or 1 hr after endotoxin. As compared to saline controls, pentoxifylline alone had no effect on mediator production, with the exception of significantly increasing 6-ketoprostaglandin F1 alpha concentration. Pentoxifylline inhibited endotoxin-induced increases in tumor necrosis factor (TNF) and inter...
Laurberg M, Saegerman C, Jacobsen S, Berg LC, Laursen SH, Hoeberg E, Sånge EA, van Galen G.Equine neonatal sepsis can be challenging to diagnose and prognosticate. Neutrophil gelatinase-associated lipocalin (NGAL), a new marker of renal damage and inflammation, can potentially be helpful. To evaluate NGAL in neonatal foals with sepsis, and assess its relation to outcome. Foals ≤ 14 days, with admission blood analysis and stored serum. NGAL was measured on stored serum from 91 foals. Foals were scored for sepsis and survival and categorized according to sepsis status (septic, sick non-septic, healthy, and uncertain sepsis status) and outcome groups (survivors and non-survivors). Th...
