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.
Bell SA, Drew CP, Wilson WD, Pusterla N.Idiopathic chronic eosinophilic pneumonia of horses is incompletely described. Objective: To describe the physical examination, clinicopathologic, histopathologic, and radiographic features and response to corticosteroid treatment of idiopathic chronic eosinophilic pneumonia of horses. Methods: Seven horses with eosinophilic pneumonia. Methods: Retrospective, descriptive study. Results: Anamnesis, clinical signs, and clinicopathologic and radiologic findings in 7 adult horses with histologically confirmed eosinophilic pneumonia were reviewed. The horses were examined for signs of chronic respi...
Pauwels FE, Schumacher J, Castro FA, Holder TE, Carroll RC, Sega GA, Rogers CW.To determine whether clinically effective concentrations of methylprednisolone or triamcinolone can be achieved in the navicular bursa after injection of methylprednisolone acetate (MPA) or triamcinolone acetonide (TA) into the distal interphalangeal joint (DIPJ) and whether clinically effective concentrations of these drugs can be achieved in the DIPJ after injecting the navicular bursa with the same doses of MPA or TA. Methods: 32 healthy horses. Methods: Horses in groups 1 through 4 received 40 mg of MPA in the DIPJ, 10 mg of TA in the DIPJ, 40 mg of MPA in the navicular bursa, and 10 mg of...
Kleine LG, Solano M, Rusckowski M, Hunt KE, Johnson KL, Kirker-Head CA.To evaluate the use of technetium Tc 99m-labeled EDTA-biotin monomer ((99m)Tc-EB1) as a scintigraphic imaging agent for soft tissue inflammatory lesions in horses. Methods: 6 healthy adult horses. Methods: First (phase 1), the agent's safety and blood-tissue clearance and an appropriate imaging protocol were determined in 6 horses. Each horse was injected with (99m)Tc-EB1 (1.1 GBq, IV, once); images were acquired at intervals during the following 24-hour period. Subsequently (phase 2), inflammation was induced via injection of 200 mg (10 mL) of mepivacaine (0.4 mg/kg) into the right neck muscu...
Frisbie DD, Al-Sobayil F, Billinghurst RC, Kawcak CE, McIlwraith CW.To discriminate between changes in biomarkers with exercise compared to changes in biomarkers with osteoarthritis (OA) in exercising horses. Methods: Sixteen, 2-year-old horses were randomly assigned either to an exercise-alone (n=8) or OA-affected (also exercised) (n=8) group. All horses had both mid-carpal joints arthroscoped and OA induced in one mid-carpal joint in the OA-affected joints of OA-affected horses. Two weeks after surgery all horses commenced a strenuous exercise program on a high-speed treadmill. Clinical outcomes and synovial fluid and serum biomarkers, were evaluated weekly....
Giri SN, Margolin SB.The effectiveness of pirfenidone ointment against thermoplasty-induced acute foreleg lameness in a double-blind study, and against acute and chronic lameness of musculoskeletal origin in an open multi-centered field trial was evaluated in this study. Thermoplasty was performed on both inner forelegs at designated locations of each horse under anesthetics. A 10% pirfenidone or placebo ointment was topically applied starting 24 hours after the thermoplasty three times daily for 7 days. For acute and chronic lameness of musculoskeletal origin, pirfenidone ointment was also applied one to three ti...
Flecknell P.The last decade has seen continued progress in both the recognition and management of animal pain. This upsurge in the use of analgesics in animals is welcome, but the main areas of use continue to be the control of postoperative or post-trauma pain, and the management of musculoskeletal pain, in companion animals and horses. The management of pain associated with other conditions, such as soft-tissue inflammation or cancer, is still relatively neglected. Pain management in farm animals, and in animals used in biomedical research could also be improved further. Apart from providing some intere...
Deeg CA, Hauck SM, Amann B, Pompetzki D, Altmann F, Raith A, Schmalzl T, Stangassinger M, Ueffing M.Equine recurrent uveitis (ERU) is an autoimmune disease that occurs with a high prevalence (10%) in horses. ERU represents the only reliable spontaneous model for human autoimmune uveitis. We already identified and characterized novel autoantigens (malate dehydrogenase, recoverin, CRALBP) by analyzing the autoantibody-binding pattern of horses affected by spontaneous recurrent uveitis (ERU) to the retinal proteome. CRALBP also seems to be relevant to human autoimmune uveitis. Proteomic screening of vitreous and retinal samples from ERU diseased cases in comparison to healthy controls has led t...
Patterson-Kane JC, Firth EC.Despite the high incidence of superficial digital flexor tendon (SDFT) injury in racehorses, the pathobiology of the condition is not clearly defined. The SDFT improves locomotor efficiency by storing elastic energy, but as a result it has low mechanical safety margins. As with the Achilles tendon in humans, rupture during athletic activity often follows accumulation of exercise and age-induced degenerative change that is not repaired by tenocytes. There is limited understanding of tenocyte biology and pathology, including responses to high mechanical strains and core temperatures during exerc...
Hoffmann C, Ellenberger C, Mattos RC, Aupperle H, Dhein S, Stief B, Schoon HA.This paper describes the histomorphological and immunohistochemical characterisation of phenotypic variations of endometrosis as well as potential etiological factors which may influence disease progression. In total, 779 endometrial biopsies were examined. These biopsies were taken in the breeding and non-breeding season (n=509), on defined days during the estrous cycle (n=70) and before and after experimentally induced bacterial endometritis (n=200). In addition to conventional histopathology, selected biopsies were investigated using alcianblue staining as well as immunohistochemical method...
McFarlane D, Holbrook TC.Equine pituitary pars intermedia dysfunction (PPID) is the result of a loss of dopaminergic inhibition of the pars intermedia secondary to neurodegeneration of periventricular hypothalamic neurons. The pathologic events contributing to development of neurodegeneration or clinical signs in equids with PPID are unknown. Chronic inflammation may contribute to initiation or progression of PPID. Objective: Horses with PPID have a distinct systemic cytokine profile compared with that of normal adult or aged horses. The cytokine profile of healthy aged horses differs from that of adult horses. Method...
Kelmer G, Doherty TJ, Elliott S, Saxton A, Fry MM, Andrews FM.Endotoxaemia is one of the most severe and ubiquitous disease processes in horses. Although dimethyl sulphoxide (DMSO) is used clinically in horses, there is no study indicating its efficacy in endotoxaemic horses. Objective: DMSO ameliorates the clinical response to i.v. lipopolysaccharide (LPS) administration. Methods: Eighteen horses were assigned randomly to one of 4 groups: Normosol-LPS (0.2 mug/kg bwt, i.v.); DMSO (1 g/kg bwt, i.v.)-saline; high-dose DMSO (1 g/kg bwt, i.v.)LPS; low-dose DMSO (20 mg/kg bwt, i.v.)-LPS. Horses participating in the DMSO-saline group were later assigned rando...
Morrissey NK, Bellenger CR, Baird AW.There are few data available regarding regulation of prostaglandin (PG) generation by equine gastric mucosae and the role of the cyclooxygenase (COX) isoforms in their production. Objective: To: 1) characterise and quantify PGE2 output in vitro; 2) examine the sensitivity of PGE2 production to exogenous bradykinin (BK) exposure; 3) determine the contribution of the COX-1 and COX-2 pathways to basal and BK-stimulated PGE2 production; and 4) measure if BK influences electrogenic ion transport in equine gastric mucosae in vitro. Methods: Full thickness gastric sheets were obtained from horses at ...
DeLuca L, Erb HN, Young JC, Perkins GA, Ainsworth DM.Chemokine expression in airway epithelium and bronchoalveolar lavage fluid (BALF) cells of horses with recurrent airway obstruction (RAO) is increased. Objective: For RAO-affected horses that are stabled and fed a pelleted ration, the addition of oral dexamethasone further improves pulmonary function and reduces inflammatory gene expression in pulmonary cells. Methods: Twelve RAO-affected horses. Methods: In a randomized cross-over experiment, the effect of feeding pellets in lieu of hay to stabled, RAO-affected horses was compared with the effect of feeding pellets and administering a 21-day ...
Delesalle C, van de Walle GR, Nolten C, Ver Donck L, van Hemelrijck A, Drinkenburg W, de Bosschere H, Claes P, Deprez P, Lefere L, Torfs S....Increased plasma (5-HT) concentrations are reported in horses predisposed to develop laminitis and after i.v. infusion of endotoxins. In the equine jejunum contractile 5-HT1A-like receptors show tachyphylaxia upon prolonged activation with 5-HT. Therefore, increased systemic 5-HT release in colic horses could play a possible role in the pathophysiology of ileus. Objective: To investigate possible increased systemic release of 5-HT in colic horses with compromised bowel and to identify the source of 5-HT overload. Methods: Concentrations of 5-HT were determined in plasma and peritoneal fluid (P...
Cook VL, Jones Shults J, McDowell M, Campbell NB, Davis JL, Blikslager AT.Absorption of endotoxin across ischaemic-injured mucosa is a major cause of mortality after colic surgery. Recent studies have shown that flunixin meglumine retards mucosal repair. Systemic lidocaine has been used to treat post operative ileus, but it also has novel anti-inflammatory effects that could improve mucosal recovery after ischaemic injury. Objective: Systemic lidocaine ameliorates the deleterious negative effects of flunixin meglumine on recovery of mucosal barrier function. Methods: Horses were treated i.v. immediately before anaesthesia with either 0.9% saline 1 ml/50 kg bwt, flun...
Driscoll N, Baia P, Fischer AT, Brauer T, Klohnen A.Large colon resection and anastomosis (LCRA) is the most aggressive method of surgical management of a colon with questionable viability. Currently, published studies are comprised mostly of broodmares and discuss short-term survival. Objective: To determine the prognosis for survival after LCRA in a diverse population of horses, report the incidence of post operative complications, and determine if associations between analysed variables and survival rate exist. Methods: The medical records of 52 horses that underwent LCRA were evaluated. Data were used to identify univariable associations wi...
Menzies-Gow NJ, Bailey SR, Berhane Y, Brooks AC, Elliott J.To determine the effect of endotoxin (lipopolysaccharide [LPS]) on vasoactive mediator production by cultured equine digital vein endothelial cells (EDVECs). Methods: EDVECs obtained from forelimb digital veins of 7 healthy adult horses. Methods: EDVECs were incubated with or without LPS (1 microg/mL) for 0, 2, 4, 6, 22, and 24 hours. The EDVECs were incubated for 18 hours with LPS (10 pg/mL to 1 microg/mL) with or without ibuprofen, cycloheximide, or L-nitroarginine methyl ester. Medium concentrations of prostacyclin, cyclic guanosine monophosphate, endothelin-1, and thromboxane A(2) were det...
Maischberger E, Irwin J, Carrington S, Duggan V.The deposition of semen, bacteria and debris in the uterus of the mare after breeding normally induces a self-limiting endometritis. The resultant fluid and inflammatory products are cleared by 48 hours post cover. Mares that are susceptible to persistent post-breeding endometritis (PPBEM) have impaired uterine defence and clearance mechanisms, making them unable to resolve this inflammation within the normal time. This persists beyond 48 hours post-breeding and causes persistent fluid accumulation within the uterus. Mares with PPBEM have an increased rate of embryonic loss and a lower overall...
Brown PA, Bodles-Brakhop A, Draghia-Akli R.In vivo electroporation dramatically improves the potency of plasmid-mediated therapies, including in large animal models. Laminitis and arthritis are common and debilitating diseases in the horse, as well as humans. Methods: The effects of growth hormone releasing hormone (GHRH) on healthy horses and on horses with laminitis that were followed for 6 months after a single intramuscular injection and electroporation of 2.5 mg of an optimized myogenic GHRH-expressing plasmid were examined. Results: In the first study on six healthy horses, we observed a significant increase in body mass by day 1...
Brooks DE, Plummer CE, Kallberg ME, Barrie KP, Ollivier FJ, Hendrix DV, Baker A, Scotty NC, Utter ME, Blackwood SE, Nunnery CM, Ben-Shlomo G....To evaluate the visual outcome of three techniques of corneal transplantation surgery in treating severe inflammatory keratopathies in the horse. Methods: Retrospective medical records study. Methods: Medical records of 206 horses that received corneal transplantation surgery at the University of Florida Veterinary Medical Center from 1993 to 2007 were reviewed. Methods: Data collected from the medical records included signalment, types of ocular lesions, type of transplant surgery performed, length of follow-up, complications, and visual outcomes. Results: Full thickness penetrating keratopla...
Riihimäki M, Raine A, Pourazar J, Sandström T, Art T, Lekeux P, Couëtil L, Pringle J.The aim of this study was to evaluate the contribution of bronchial epithelium to airway inflammation, with focus on mRNA and protein expression of cytokines of innate immunity IL-6, IL-10 and TNF-alpha, in horses with Recurrent Airway Obstruction (RAO) during exacerbation and in remission. Results: Despite marked clinical and physiologic alterations between exacerbation and after remission in the RAO horses no differences were detected in either cytokine mRNA or protein levels. Moreover, the expression of investigated cytokines in RAO horses on pasture did not differ from controls. In compari...
Lores M, Ortenburger AI.3 horses were evaluated for signs of colic; cecocolic intussusception was detected. Results: Abnormalities detected included diminished intestinal sounds, inflammatory leukogram, dehydration, unremarkable fi ndings via rectal palpation, and ultrasonographic evidence of large intestine intussusception. Laparotomy revealed cecocolic intussusception. Results: Cecal bypass via side-to-side ileocolic anastomosis without ileal transection was performed in each horse by use of an intraluminal anastomosis stapler device. Postoperative complications were minimal, and all horses recovered rapidly and we...
Berg LC, Lenz J, Kjelgaard-Hansen M, Thomsen PD, Jacobsen S.More sensitive and specific diagnostic methods for early detection of changes in the joint cartilage are needed. Cartilage-derived retinoic acid-sensitive protein (CD-RAP) is a potential marker of cartilage synthesis and regeneration. This is the first study on equine CD-RAP. Objective: To evaluate the ability of a commercially available human sandwich ELISA assay to detect equine CD-RAP in synovial fluid from healthy and diseased joints. Methods: Synovial fluid was collected from 28 horses with no signs of joint disease and from 5 with induced inflammatory arthritis. CD-RAP concentrations wer...
Le KM, Caston SS, Hossetter JM, Hay Kraus BL.To evaluate the analgesic and tissue effects of liposomal bupivacaine administered SC as an abaxial sesamoid nerve block in horses with experimentally induced lameness. Methods: 6 healthy mature light-breed horses. Methods: In a randomized crossover study, a circumferential hoof clamp was applied to a forelimb to induce reversible lameness. An abaxial sesamoid nerve block of the lame forelimb was performed by SC perineural injection of 10 mg of liposomal bupivacaine or bupivacaine HCl/site. Quantitative gait data were objectively obtained with a body-mounted inertial sensor system before (base...
Grulke S, Deby-Dupont G, Cassart D, Gangl M, Caudron I, Lamy M, Serteyn D.In cases of equine acute abdominal disease, where pancreatic damage is suspected, pancreatic damage can be assessed by measuring increased trypsin activity in the plasma of horses suffering intestinal obstruction and severe shock. The pancreas is particularly vulnerable to splanchnic hypoperfusion because it is a highly active tissue. In this study, 10 horses undergoing abdominal surgery for intestinal obstruction were assayed for trypsin activity on admission and, because of extensive intestinal lesions that were not amenable to surgery, euthanasia was selected; the pancreas was removed befor...
Salinas C, Barriga K, Albornoz A, Alarcon P, Quiroga J, Uberti B, Sarmiento J, Henriquez C, Ehrenfeld P, Burgos RA, Moran G.Neutrophils display an array of biological functions including the formation of neutrophil extracellular traps (NETs), web-like structures specialized in trapping, neutralizing, killing and preventing microbial dissemination within the host. However, NETs contribute to a number of inflammatory pathologies, including severe equine asthma. Tamoxifen (TX) is a selective estrogen receptor modulator which belongs to the triphenylethyllenes group of molecules, and which is used as a treatment in all stages of estrogen-positive human breast cancer. Our previous results suggest that tamoxifen can modu...
Ferreira-Dias G, Nequin LG, King SS.Pathologic changes in the endometrium of mares may be rated according to Kenney's method of classification. Category I endometrium contains healthy tissue with no or few widely scattered pathologic changes. At the opposite end, severe widespread pathologic changes are associated with category III. Uterine biopsy specimens were collected aseptically from 16 mares during the estrous and diestrous stages of the cycle. Pathologic changes were evaluated, using light microscopy, and endometrium was classified as Kenney's category I, II, or III. Endometrial tissue of category I (n = 5 mares in estrus...
Freeman KP, Roszel JF, Slusher SH, Castro M.Histochemical stains were applied to six equine uterine biopsies representative of the physiologic breeding season, Spring and Fall transition, and Winter anestrus periods. These were compared with uterine biopsies from six mares with intrauterine urine pooling, eight mares used to study the uterine response to indwelling catheterization, and necropsy specimens from four pregnant mares at approximately 60 or 100 d of gestation. Alcian blue staining at pH 2.5 or 1.0 was used to identify the presence of carboxylated and sulfated acid mucins or only suflated acid mucins, respectively. Periodic ac...
de Grauw JC.Diseases affecting synovial joints are a major cause of chronic disability both in humans and in companion animal species, most notably dogs and horses. As progressive deterioration of the articular cartilage is the hallmark of degenerative joint disease or osteoarthritis, research efforts traditionally tended to focus primarily on cartilage pathology. However, in recent years it has become clear that synovial joints should be considered intricate organs in their own right, with each of the constituent tissues (cartilage, bone, and synovial membrane) interacting with each other both in health ...
Brown MP, Trumble TN, Sandy JD, Merritt KA.To determine whether dimethylmethylene blue (DMMB) analysis, when combined with agarose gel filtration chromatography (Superose 6), can be performed instead of fluorophore-assisted carbohydrate electrophoresis (FACE) to determine chondroitin sulfate (CS) chain length in synovial fluid (SF). Methods: SF was obtained from (1) normal horses after 8 weeks of rest, (2) the same horses after 9 months of treadmill training, and (3) horses with osteochondral (OC) injury from racing. SF CS concentrations and chain lengths were determined by gel chromatography and DMMB analysis and compared with previou...
Bertone AL, McIlwraith CW, Jones RL, Norrdin RW, Radin MJ, Lebel JL.To evaluate the effects of 5 treatments on clinical responses, synovial fluid analysis, radiographic changes, bacteriologic culture results of the synovial fluid and synovial membrane, microscopic characteristics of the synovial membrane, and articular cartilage histochemistry, Staphylococcus aureus organisms (1.6 X 10(6) colony-forming units) were inoculated into the tarsocrural joints of 12 horses (n = 24 joints; 2 joints/horse). Each horse was given phenylbutazone (2 g) orally, every 24 hours, beginning 24 hours after inoculation. Two horses (ie, 4 joints) were not given other treatment (co...
Davis JL, Marshall JF, Papich MG, Blikslager AT, Campbell NB.The purpose of this study was to determine the pharmacokinetics of deracoxib following oral administration to horses. In addition, in vitro equine whole blood cyclooxygenase (COX) selectivity assays were performed. Six healthy adult horses were administered deracoxib (2 mg/kg) orally. Plasma samples were collected prior to drug administration (time 0), and 10, 20, 40 min and 1, 1.5, 2, 4, 6, 8, 12, 24, and 48 h after administration for analysis with high pressure liquid chromatography using ultraviolet detection. Following PO administration, deracoxib had a long elimination half-life (t(...
Nixon AJ, Pool RR.Osteochondral fragments from the axial proximoplantar/proximopalmar region of the proximal phalanx were removed from 38 joints in 30 horses. Ninety-three percent of the horses were Standardbreds, and 28 of the 30 had a low-grade lameness. All but 1 of the horses had hind limb involvement. A total of 43 fragments were removed. Most (71%) of the fragments involved the medial aspect of the joint and had to be dissected from a covering of synovial tissue. Histologically, the circumference of most fragments consisted of a transition zone at the attachment of the joint capsule, a region of nonarticu...
Bundgaard L, Jacobsen S, Dyrlund TF, Sørensen MA, Harman VM, Beynon RJ, Brownridge PJ, Petersen LJ, Bendixen E.The aim of this study was the development of a quantitative assay that could support future studies of a panel of acute phase proteins (APPs) in the horse. The assay was based on a quantification concatamer (QconCAT) coupled to selected reaction monitoring methodology. Thirty-two peptides, corresponding to 13 putative or confirmed APPs for the Equus caballus (equine) species were selected for the design of a QconCAT construct. The gene encoding the QconCAT was synthesized and expressed as an isotope-labeled chimaeric protein in Escherichia coli. The QconCAT tryptic peptides were analyzed on a ...
Bernick A, Nieth J, Wehrend A.Urachal patency is an umbilical disease in newborn foals. Etiologically, either the closure of the urachus remains absent after birth (persistent urachus) or the urachus was already closed and reopens at a later time (patent urachus). The most common causes of patent urachus are congenital defects, tearing of the navel above the predilection site, trauma, increased intravesical or abdominal pressure and umbilical infections. Patent urachus occurs more frequently in premature or weak and immunocompromised foals. Colts are more often affected than fillies. Typical clinical signs are apparent imm...
Sandersen C, Mouithys-Mickalad A, de la Rebière G, Deby G, Serteyn D, Franck T.To investigate the effect of acepromazine (ACP) on reactive oxygen species (ROS) production by stimulated equine neutrophils. Methods: Ex vivo biochemical experiments. Methods: Isolated neutrophils from healthy untreated horses. Methods: Neutrophils were incubated with ACP at concentrations of 10(-4), 10(-5) or 10(-6) M and then stimulated with phorbol-myristate-acetate (PMA) before measurement of lucigenin-enhanced chemiluminescence (CL). In a second experiment neutrophils were incubated in the presence of α-keto-γ methylthiobutyric acid (KMB) and treated with ACP at concentrations of 10(-4...
Perrone G, Lastra Y, González C, Caggiano N, Giménez R, Pareja R, De Simone E.Osteoarthritis (OA) is the most prevalent arthropathy in sport horses. The administration of a platelet lysate (PL) is an alternative method for the treatment of musculoskeletal conditions. The mechanisms by which PL exerts its beneficial effects have not been determined, and less is known about its effect on the activity of the proteolytic enzymes of the synovial fluid of equines with OA. In this work, the effect of the administration of PL to horses with OA was analyzed both clinically and molecularly by determining the levels of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9...
Ceusters JD, Serteyn DA, Minguet G, de la Rebière de Pouyade G, Romainville J, Deby-Dupont GP, Mouithys-Mickalad AA, Franck TJ.Horses are particularly sensitive and exposed to excessive inflammatory responses evolving toward an important stimulation of polymorphonuclear neutrophils (PMNs). The aim of this work was to stimulate equine neutrophils in whole blood and to evaluate their response by measuring the release of total and active myeloperoxidase (MPO) and total elastase, considered as markers of neutrophil stimulation and degranulation. Because of the critical importance of the concomitant presence of LPS and TNF-α in equine pathological situations, we combined these two natural mediators to stimulate PMN and co...
Grady SE, Lescun TB, Moore GE, Cooper BR, Davern AJ, Brunner TJ, Taylor SD.The objective was to compare the analgesic efficacy of ketorolac tromethamine (KT) and two other nonsteroidal anti-inflammatory drugs (NSAIDs), including flunixin meglumine (FM) and phenylbutazone (PB), using a heart bar shoe (HBS) model of reversible foot lameness in horses. Nine adult horses were used in a blinded, randomized, placebo-controlled crossover study. After induction of left front limb lameness using a modified HBS model, one of three NSAIDs (KT, 2.0 mg/kg IV; FM, 1.1 mg/kg IV; PB, 4.4 mg/kg IV) or saline (placebo) was administered IV as a single dose. Lameness was assessed eve...
Vrins A, Doucet M, Nunez-Ochoa L.A retrospective of 69 bronchoalveolar lavages (BAL) on horses was done to investigate the relationship between bronchoalveolar cell types and clinical signs in horses with small airway disease. Horses were grouped according to clinical findings. The groups were as follows: I. cough only (n = 14), II. cough with mucopurulent secretions in the trachea (n = 14), III. cough, mucopurulent secretions in the trachea and abnormal lung sounds (n = 24) and IV., all of the above plus dyspnea at rest (n = 17). An asymptomatic group was formed from horses in the same population to serve as control (n = 8)....
Macleod KD, Scott DW, Erb HN.A retrospective study was performed to assess the prevalence of apoptotic epidermal keratinocytes in biopsy specimens from 226 horses with inflammatory dermatoses and from 27 normal specimens. One or more apoptotic keratinocytes were found in specimens from 28 of 226 (12%) horses with various dermatoses, and in one of 27 (4%) specimens from normal horses. The prevalence (proportion of cases with apoptotic epidermal keratinocytes) of apoptotic keratinocytes in the group composed of discoid lupus erythematosus, erythema multiforme, photodermatitis, and systemic lupus erythematosus was significan...
Schumacher J, Spano JS, Moll HD.Peritoneal fluid was collected from 15 clinically normal horses and was analyzed for nucleated cell (NC) counts and specific gravity. Six horses (controls, group 1) were subjected to abdominocentesis only, with a teat cannula, every 24 hours for 5 days. There were no marked changes in the peritoneal fluid of these horses over the 5-day period. Peritoneal fluid was collected from 6 other horses (group 2) with an 8.89-cm 18-gauge needle. The needle was then advanced until intestinal fluid was obtained. Peritoneal fluid was then collected with teat cannulas at 24-hour intervals for an additional ...
Tsujita H, Plummer CE.To describe and evaluate intrastromal and subconjunctival injection of voriconazole for the therapy of deep corneal stromal abscess (DSA) in horses. Methods: A retrospective clinical study describing the indications for intrastromal and subconjunctival voriconazole injection and the outcomes of this procedure in two eyes of two horses. Methods: The two horses in this study failed to respond to medical therapy. Treatment with intracorneal and subconjunctival administration of 1% voriconazole was performed in this study. Results: Treatment with intracorneal and subconjunctival administration of ...
Klei TR, Turk MA, McClure JR, Holmes RA, Dennis VA, Chapman MR.Eight of 10 pony foals reared under helminth-free conditions were inoculated PO with 50 Strongylus vulgaris infective larvae/week for 4 weeks, at which time 1 foal died of acute verminous arteritis. Inoculation of 7 remaining foals continued at 2-week intervals for 20 weeks. Of the 7 foals, 3 were treated with ivermectin (0.2 mg/kg of body weight) in an oral paste formulation at experiment weeks 8, 16, 24; 4 foals were not treated. Two foals were not inoculated or treated and served as controls. After the first ivermectin treatment, ivermectin-treated foals had fewer days (12 +/- 2.9) with rec...
May SA, Hooke RE, Lees P.Prostaglandin E2 (PGE2) and stromelysin are produced by equine chondrocytes and synovial cells in vitro in response to recombinant human (rh) interleukin-1 (IL-1) alpha and beta, and equine mononuclear cell supernatants (MCS) containing IL-1. However, culture conditions are important. PGE2 concentrations increase in proportion to the concentration of fetal calf serum (FCS) in the culture medium, whereas stromelysin concentrations are inversely proportional to the concentration of FCS. Equine MCS, containing a lower concentration of IL-1 than the concentration of rhIL-1 used in these experiment...
Yamagata M, Wilkie DA, Gilger BC.Eosinophilic keratoconjunctivitis was diagnosed in 7 horses at The Ohio State University between 1976 and 1994. All horses had moderate-to-severe blepharospasm, chemosis, and conjunctival hyperemia; epiphora; and extensive yellow-to-white caseous mucoid discharge. Corneal ulcers associated with this disease were perilimbal and extended centrally. All ulcers were covered with a white necrotic plaque firmly attached to the underlying cornea. Other ophthalmic abnormalities were not detected. Corneal scrapings examined cytologically contained numerous eosinophils interspersed between epithelial ce...
Dhama K, Kapoor S, Pawaiya RV, Chakraborty S, Tiwari R, Verma AK.A fascinating and important arbovirus is Ross River Virus (RRV) which is endemic and epizootic in nature in certain parts of the world. RRV is a member of the genus Alphavirus within the Semliki Forest complex of the family Togaviridae, which also includes the Getah virus. The virus is responsible for causing disease both in humans as well as horses. Mosquito species (Aedes camptorhynchus and Aedes vigilax; Culex annulirostris) are the most important vector for this virus. In places of low temperature as well as low rainfall or where there is lack of habitat of mosquito there is also limitatio...
Frean SP, Bryant CE, Fröling IL, Elliott J, Lees P.Recent research in several species has suggested nitric oxide (NO) as a mediator of articular cartilage damage and an inhibitor of cartilage matrix neosynthesis. This study investigated NO production by cultured equine articular chondrocytes in response to 2 arthritogenic molecules, namely lipopolysaccharide (LPS) and interleukin-1 beta (IL-1 beta), and compared NO production by cultured equine synoviocytes stimulated with LPS. Synoviocytes exhibited a low basal level of NO synthesis (measured as nitrite, a NO metabolite) that was neither significantly increased nor decreased by exposure to LP...
O'Callaghan MW, Pascoe JR, Tyler WS, Mason DK.This paper reviews a series of clinical, post mortem and imaging studies on exercise-induced pulmonary haemorrhage (EIPH) performed on 26 Thoroughbred racehorses. Post mortem techniques included routine gross, subgross and histological examination; coloured latex perfusions of pulmonary and bronchial circulations; and microradiography and computerised tomography scans of lungs with contrast injected vasculature. The major lesions were multiple, separate and coalescing foci of moderately proliferative small airway disease accompanied by intense neovascularisation of the bronchial circulation. A...
Brunner TJ, Lescun TB, Moore GE, Grady SE, Davern AJ, Taylor SD.The mechanism by which nonsteroidal anti-inflammatory drugs mitigate pain caused by a heart bar shoe (HBS) model of lameness is unknown. The purpose of this study was to determine if this HBS model of lameness induces inflammation in horses. Five healthy adult horses from a university teaching herd were enrolled. A custom HBS was applied to the left front foot of each horse, followed by induction of the American Association of Equine Practitioners Lameness Score of 4. Inflammatory markers including serum amyloid A (SAA) concentration, local venous tumor necrosis factor alpha and prostaglandin ...
Boesen MI, Nanni S, Langberg H, Boesen M, Falk-Ronne J, Bliddal H, Torp-Pedersen S.Sclerosing therapy has in recent studies showed promising results in patients with clinically and ultrasonographically diagnosed tendinosis in Achilles and patellar tendons. The aim of this investigation was to study the presence of intratendinous colour Doppler (CD) flow in horses with clinically diagnosed chronic tendinopathy and to test if experience from human studies could be extrapolated to horses. Special interest was focused on the treatment with sclerosing therapy and whether we could obtain the same successful peroperative findings as in humans. Four horses with clinically diagnosed ...
Schaffer PA, Wobeser B, Dennis MM, Duncan CG.A retrospective study evaluated the clinical data and histologic features of non-neoplastic dermatologic lesions in skin biopsies from horses, donkeys, and mules submitted over a 10-year period to the Colorado State University Diagnostic Medicine Center and to the University of Saskatchewan Western College of Veterinary Medicine and Prairie Diagnostic Services. A total of 1793 non-neoplastic biopsies were available for analysis. Based on the histologic description and morphologic diagnosis, each submission was classified as inflammatory, or non-neoplastic/non-inflammatory. Results of this stud...
Ainsworth DM, Appleton JA, Antczak DF, Santiago MA, Aviza G.A controlled experimental system for the evaluation of pulmonary immune responses in horses with "heaves" (recurrent airway obstruction) has been developed. We hypothesized that the humoral immune response to an inhaled antigen in diseased horses would be different from that of healthy horses and that chronic pulmonary inflammation would bias the production of IgG isotypes in diseased horses as compared to healthy horses. Healthy and affected horses were housed in a natural challenge environment (stabled, fed dusty hay) and exposed by inhalation, to a nebulized solution of keyhole limpet hemoc...
