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.
Higgins AJ, Lees P, Taylor JB.In a two part cross-over experiment, acute inflammatory exudates were induced in 7 ponies by subcutaneous implantation of 3 sterile carrageenin-soaked polyester sponge strips. Treatment comprised a single therapeutic geenin-soaked polyester sponge strips. Treatment comprised a single therapeutic dose of 4.4 mg/kg phenylbutazone (PBZ) administered intravenously at the time of sponge implantation. Exudates were harvested at 6, 12 and 24 hours and examined for leukocyte and erythrocyte numbers using the improved Neubauer technique; for eicosanoids by radioimmunoassay and by high performance liqui...
Cooley PL, Milvae R, Riis RC, Laratta LJ.A study was performed to identify prostacyclin (PGI2) in equine aqueous humor, demonstrate an increase in PGI2 following anterior chamber paracentesis, and determine the effects of subconjunctival injection of flunixin meglumine on PGI2 accumulation. Twenty ponies were found to be normal upon ocular examination and were placed under general anesthesia. Anterior chamber paracentesis was performed in both eyes (right and left); immediately afterward, 25 mg of flunixin meglumine was injected (subconjunctivally) in the left eye. Aqueous paracentesis was performed 1.5 hours later (both eyes). Aqueo...
Van Amstel SR, Ross M, van den Bergh SS.A case of maduromycosis mycetoma caused by Madurella mycetomatis is reported. The horse presented with multiple subcutaneous swelling over the right scapula. There were no discharging fistulae present. Macroscopically the lesion contained a black granular material embedded in a granulomatous mass. Microscopically large numbers of microcolonies were present containing segmented hyphae. No typical chlamydospores were observed. Cultures yielded a fungus identified as Madurella mycetomatis. Treatment consisted of surgical excision and local treatment with thiabendazole powder.
Blue HB, Blue MG, Kenney RM, Merritt TL.Forty uterine fluid samples were obtained from 4 mares classified as resistant to uterine bacterial infection. The uterus of each mare was flushed with 50 ml of saline solution during estrus and diestrus of successive estrous cycles. Bacteria or fungi were isolated from 4 samples, and 7 additional samples were obtained from a mare with active intrauterine infection. Fluid volumes obtained during estrus (means = 40.3 +/- 11 ml) tended to be greater than those recovered during diestrus (means = 36.8 +/- 7.9 ml), but the difference was not significant. Concentrations and yields of protein in reco...
Rousseaux CG, Futcher KG, Clark EG, Naylor JM.Two cases of cauda equina neuritis are compared and contrasted. Neurological deficits of the tail and perineum were noted and functional deficits were seen in gait, urination, defecation and cranial nerve function. Lesions consisted of nonsuppurative inflammation of the nerve trunks and proliferation of the perineurium of the cauda equina. Cranial nerve involvement in one case supported a diagnosis of polyneuritis equi rather than cauda equina neuritis. The possible etiologies and pathogenesis of this disease are discussed.
Higgins AJ, Lees P, Wright JA.In a series of experiments to examine equine inflammatory exudates for the presence of metabolites of arachidonic acid, including prostaglandin E2 (PGE2), a model for the induction and collection of exudates in ponies has been developed. Multiperforated polypropylene practice golf balls implanted subcutaneously in the mid-neck region were well tolerated and proved to be the most successful model. One such cage was implanted in the neck of each of seven ponies. Inflammatory exudates were induced by injecting 3.0 or 0.5 ml carrageenin into the cages and aspirates collected between three and 48 h...
Coignoul FL, Bertram TA, Roth JA, Cheville NF.Neutrophils from 4 pony foals, 3 lactating pony mares, and 3 nonlactating mares were evaluated ultrastructurally and by in vitro function tests. Neutrophils from foals had significantly (P = 0.05) less random migration than neutrophils from mares; values in tests for iodination and Staphylococcus aureus ingestion were also lower with foal neutrophils. Neutrophils from lactating mares had lower responses to iodination, antibody-dependent cell-mediated cytotoxicity, and random migration tests than did neutrophils from nonlactating mares. Ultrastructurally, granule concentration did not differ si...
Higgins AJ, Lees P.Arachidonic acid is a polyunsaturated fatty acid covalently bound in esterified form in the cell membranes of most body cells. Following irritation or injury, arachidonic acid is released and oxygenated by enzyme systems leading to the formation of an important group of inflammatory mediators, the eicosanoids. It is now recognised that eicosanoid release is fundamental to the inflammatory process. For example, the prostaglandins and other prostanoids, products of the cyclooxygenase enzyme pathway, have potent inflammatory properties and prostaglandin E2 is readily detectable in equine acute in...
Gunson DE, Halliwell RE, Minor RR.A 2-year-old female horse had large areas of hyperextensible, fragile skin that were interspersed with areas of normal skin. Affected skin tore easily and contained reduced amounts of dermal collagen. Collagen fibers were fragmented and disorganized, and in trichrome-stained sections, many fibers had abnormal red-stained centers. Electron microscopy showed that many collagen fibers had discrete foci of degradation in which the fibrils were fragmented, loosely packed, and widely separated by granular material. Collagen fibril fragments were present in secondary lysosomes in dermal fibroblasts, ...
Dik KJ.Radiographically, joint ill in foals is subdivided into four different types: Type P - osteomyelitis in the meta- and/or epiphysis adjacent to the physis. Type E - osteomyelitis in the epiphyseal subchondral bone. Type S - synovitis confined to the joint itself. Type T - osteomyelitis in the small tarsal bones. The radiographical features corresponding with the different types, the relationship between the radiological, pathological, bacterial and clinical findings, and the recommended radiographic procedure are discussed in detail.
Lindberg R.A morphological study on equine granulomatous enteritis (EGE) in 13 horses is presented. All horses were young (1 to 5 years old) standardbreds. Based on gross pathology, cases were classified into those with diffuse (11 cases) and those with localized (2 cases) small bowel lesions. The granulomatous reaction in the gut was marked by diffuse and patchy infiltrates and distinct granulomas, composed of epithelioid cells, macrophages and lymphoid cells, and was devoid of necrosis. Salient accompanying features of the small bowel included lymphoid hyperplasia, peri-lymphatic and transmural inflamm...
Steckel RR, Page EH, Geddes LA, Van Vleet JF.The effect of low-level direct-current stimulation on skin wound healing in the horse was assessed. Self-sustaining electrical circuits with electrodes were implanted subcutaneously in or near the wound. Stimulation by direct current (10 or 20 microA) was used to determine the effect on equine skin healing. The efficacy of electrotherapy was evaluated by sequentially comparing the clinical appearance of the wound and measuring the size of the granulating wound bed. The histologic appearance of the healing stimulated wounds was compared with that in nonstimulated control wounds created on 9 hor...
Geiser DR, Walker RD.The pathophysiology and histopathology of thermal burns in large animals is very similar to that in humans. Burns are classified as first degree, superficial and deep second degree, third degree, and fourth degree, depending upon the depth of thermal injury. Most severe burns will produce a local and a systemic response--both of which must be properly treated to increase the patient's chances for survival. The systemic response is mainly characterized by hypovolemia, fluid and electrolyte loss, protein loss, pulmonary edema, increased caloric requirements, and depressed immune responses. The l...
Nixon AJ, Stashak TS, Smith FW, Norrdin RW.Carbon fibre-polylactic acid composites and monofilament non-absorbable suture material were compared for the repair of surgically transected superficial digital flexor tendons in 10 horses. All surgical wounds healed by first intention. The repaired tendons were enlarged, the carbon implanted tendons being larger than those sutured. The horses were killed at six, eight, 12,20 or 24 weeks. Greater fibrous thickening occurred in tendons repaired with carbon fibre, especially at 12 weeks postoperatively. Carbon fibre incited a greater histological response with macrophages, lymphocytes, plasma c...
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...
Valberg SJ, McKinnon AO.Five horses with fatal clostridial cellulitis are described. The characteristic findings were the rapid development of a crepitant swelling with an associated toxemia, which in four cases followed intramuscular injections. The clinical features, diagnostic techniques and pathogenesis are discussed. The importance of an early diagnosis is emphasized.
Turk MA, Klei TR.Eighteen parasite-free pony foals were infected orally with 500 third stage larvae of Strongylus vulgaris. At 56 days after infection, six ponies were treated with intramuscular ivermectin (22, 23-dihydroavermectin B1); six were treated with oral ivermectin; and six were not treated. Necropsy was done 91 days after infection to study the pathologic effects of migrating S. vulgaris larvae and to determine the efficacy of ivermectin in attenuation of S. vulgaris-induced lesions. Larval migration induced eosinophilic inflammation of the liver, spleen, mesenteric, colic and cecal lymph nodes, and ...
Meyer H.Skin diseases of the horse can be produced or enhanced through nutrient deficiency, intestinal formation of detrimental substances, photosensitizing compounds and by intake of allergenes. An exact case history regarding feeding is useful for evaluation of every skin abnormality.
Mayhew IG, Brewer BD, Reinhard MK, Greiner EC.A fifth stage Strongylus vulgaris migrated through the spinal cord of a 2-year-old, male donkey resulting in progressive paraparesis and then tetraplegia. A profound neutrophilic pleocytosis was detected on analysis of cerebrospinal fluid. The parasite appeared to have entered the mid-lumbar spinal cord, migrated to the cranial thoracic segments, exited, then re-entered the spinal cord a few segments craniad. It then traveled further cranially and was found in the third cervical spinal cord segment. Some parts of the lesion were remarkably free from tissue necrosis, hemorrhage and inflammation...
MacLean AA, Robertson-Smith RG.The upper respiratory tract of a pony mare with marked exercise intolerance and respiratory stridor was examined with a flexible fibreoptoscope. Both arytenoids were adducted and distorted. A diagnosis of bilateral chondritis of the arytenoids was made and confirmed at autopsy after surgery to enlarge the rima glottidis was unsuccessful. Other space occupying lesions of the rima glottidis are discussed and theories on the aetiology are postulated.
García-Sacristán A, Casanueva CR, Castilla C, Labadia A.The presence and types of alpha and beta adrenergic receptors in the urethra and prostate of the horse were studied in vitro using adrenergic agonist and antagonist drugs. The existence of these receptors was shown. This finding was based on the observation that the contractile action was mediated by adrenergic receptors of alpha-1 type, although in the prostate alpha-2 type receptors also participated. Relaxation in both tissues was controlled by receptors of the beta-2 type.
Grabner A.Using a fibreoptic endoscope ("small gastroscope" with outside diameter of 9.3 mm) a simple and sparing inspection of the guttural pouch is performed. The flap-type tube cover is opened by means of medial leverage with a guidance probe shifted through the work duct of the endoscope. The same procedure is used in diagnostic specimen collection and therapeutical measures such as irrigations. Guttural pouch topography and pathological disorders are illustrated by endoscopic photography. The different diseases such as follicular hyperplasia, ascending pharyngeal catarrh, perforating abscesses of t...
Hilbert BJ, Rowley G, Antonas KN.A method previously described was used to determine the hyaluronic acid concentration in synovia from normal and arthritic horse joints. The concentration of hyaluronic acid in the synovia from arthritic joints was found to be significantly lower than the concentration in fluid from normal joints.
Bottoms GD, Johnson MA, Lamar CH, Fessler JF, Turek JJ.Dispersed equine vascular endothelial cells grown in tissue culture, and freshly isolated neutrophils were used to determine direct effects of endotoxin on cyclooxygenase and lipoxygenase products. Endothelial cells (10(7)/ml) or neutrophils (2 X 10(6)/ml) were incubated with (a) buffer, (b) endotoxin (10 micrograms/ml), (c) endotoxin + flunixin meglumine (10 micrograms/ml), or (d) calcium ionophore, A23187 (10 micrograms/ml). Thromboxane (TxB2), prostacyclin (6-keto-PGF1 alpha), and leukotriene C4 (LTC4) were determined in the incubation fluid by radioimmunoassay. Thromboxane and prostacyclin...
Bonhomme D, Werts C.Leptospirosis is a zoonotic infectious disease affecting all vertebrates. It is caused by species of the genus Leptospira, among which are the highly pathogenic L. interrogans. Different mammals can be either resistant or susceptible to the disease which can present a large variety of symptoms. Humans are mostly asymptomatic after infection but can have in some cases symptoms varying from a flu-like syndrome to more severe forms such as Weil's disease, potentially leading to multiorgan failure and death. Similarly, cattle, pigs, and horses can suffer from acute forms of the disease, including ...
Lee GKC, Kang H, Beeler-Marfisi J, Sears W, Lillie BN, Bienzle D.Salivary scavenger and agglutinin (SALSA) is a secreted protein with various immunomodulatory roles. In humans, the protein agglutinates and inactivates microorganisms, and inhibits the release of pro-inflammatory cytokines. Saliva, which is rich in SALSA, accelerates bacterial phagocytosis, but SALSA's contribution is unclear. In horses, the functions of SALSA in inflammation remain undetermined, so they were investigated through phagocytosis and cytokine assays. Equine SALSA was purified from duodenal tissue, which contains abundant SALSA. To assess phagocytosis, fluorescently-labelled bacte...
Galbraith EA, McKellar QA.Flunixin was highly protein bound in the serum of dogs (92.2 per cent), goats (84.8 per cent) and horses (86.9 per cent). Meclofenamic acid was also highly protein bound, although there were larger differences between the extent of the binding in dogs (90.3 per cent), goats (84.7 per cent) and horses (99.8 per cent). Both flunixin and meclofenamic acid were potent inhibitors of the in vitro generation of thromboxane (Tx) B2 in blood. Flunixin inhibited the generation of TxB2 by 50 per cent of the maximum response (IC50) in dog, goat and horse blood at concentrations of 0.10, 0.02 and 0.04 micr...
Pomorski Z, Pinkiewicz E, Grzebuła S.In the studies attempts were to demonstrate the occurrence of immunological reactivity against antigens of the lens and tunica vascularis of the eye in periodical inflammation of eyes in horses. For this purpose antigens from the lens and tunica vascularis of the eye, prepared in our laboratory, were used in the experiments. The reactivity of horses with monthly symptoms of blindness against the above antigens was determined in vivo (skin tests and PCA) and in vitro (ID reaction). The results obtained mainly in skin tests account for its occurrence in some percentage of diseased animals, becau...
Niedzwiedz A, Jaworski Z, Kubiak K.Equine recurrent airway obstruction (RAO), also known as heaves, is one of the most common respiratory problems in older horses. When RAO-affected horses stay pastured or in a dust-free environment for a prolonged time, clinical signs as well as airway inflammation wane. A number of environmental, immunologic, infectious, and genetic factors play an important role in the pathogenesis of RAO, and the immunologic basis of this disease is still poorly understood. Objective: The aim of this study was to investigate the concentrations of allergen-specific IgE in the serum of horses suffering from R...
Shiels IA, Sanderson SD, Taylor SM.To develop an in vitro model of uveitis based on an ex situ perfused eye to evaluate the anti-inflammatory activity of new pharmacological products. Methods: Eyes were removed from more than 60 dogs and 9 horses immediately after euthanasia and perfused with nutrient medium through the lateral long ciliary artery. Perfused eyes produced aqueous humour, and perfusion pressure was adjusted to obtain an intraocular pressure in the physiological range. When the eyes were treated with histamine, a complement C5a analogue peptide and hydrogen peroxide, typical signs of uveitis were produced. These i...
Peyron JG.Viscosupplementation (restoring the rheological properties of a tissue matrix) by injection of hyaluronan into the joints has been in use for 2 decades, mostly for osteoarthritis (OA) of the knee, using doses of 20-25 mg of hyaluronan of 500,000 to 2,500,000 M(r), in sequences of 2 to 10 weekly injections. Pain relief appears in a few days, progresses over a few weeks, and often lasts several months. Some data suggest the benefit can last 6 months to one year. Tolerance is universally reported as very good. Those responding to hyaluronan are 65-80%, compared to 30-35% responding to control. Co...
Degroote RL, Hauck SM, Treutlein G, Amann B, Fröhlich KJ, Kremmer E, Merl J, Stangassinger M, Ueffing M, Deeg CA.Autoimmune uveitis is characterized by crossing of blood-retinal barrier (BRB) by autoaggressive immune cells. Equine recurrent uveitis (ERU) is a valuable spontaneous model for autoimmune uveitis and analyses of differentially expressed proteins in ERU unraveled changed protein clusters in target tissues and immune system. Healthy eyes are devoid of leukocytes. In ERU, however, leukocytes enter the inner eye and subsequently destroy it. Molecular mechanisms enabling cell migration through BRB still remain elusive. Previously, we detected decreased talin 1 expression in blood-derived granulocy...
Hansson E, Skiöldebrand E.To treat osteoarthritic chondrocytes and thereby reduce the inflammation with a drug combination that primarily affects 5-HT- and ATP-evoked Ca2+ signaling. In osteoarthritic chondrocytes, Ca2+ signaling is elevated, resulting in increased production of ATP and inflammatory mediators. The expression of TLR4 and Na+/K+-ATPase was used to evaluate the inflammatory status of the cells. Methods: Equine chondrocytes were collected from joints with mild structural osteoarthritic changes and cultured in monolayers. The cells were treated with a combination of bupivacaine (1 pM) and sildenafil (1 ...
Parrilla Hernández S, Franck T, Munaut C, Feyereisen É, Piret J, Farnir F, Reigner F, Barrière P, Deleuze S.Myeloperoxidase (MPO), as a marker of neutrophil activation, has been associated with equine endometritis. However, in absence of inflammation, MPO is constantly detected in the uterine lumen of estrous mares. The aim of this study was to characterize MPO in the uterus of mares under physiological conditions as a first step to better understand the role of this enzyme in equine reproduction. Total and active MPO concentrations were determined, by ELISA and SIEFED assay, respectively, in low-volume lavages from mares in estrus ( = 26), diestrus ( = 18) and anestrus ( = 8) in absence of endometr...
Sedgwick AD, Lees P, Dawson J, May SA.The migration of leucocytes to sites of acute and chronic inflammation is an event of central importance to the maintenance of inflammatory processes; extravascular leucocytes are responsible for generating chemical mediators of inflammation and the phagocytosis of particulate matter. They may also be involved in the conversion of acute to chronic inflammatory lesions. Leucocytes are attracted to sites of tissue injury by a range of chemoattractants. This paper describes the development of a method for separating on Percoll gradients purified populations of equine polymorphonuclear and mononuc...
Andreassen SM, Berg LC, Nielsen SS, Kristensen AT, Jacobsen S.Studies in humans have shown that haemostatic and inflammatory pathways both play important roles in the pathogenesis of joint disease. The aim of this study was to assess mRNA expression of haemostatic and inflammatory factors in cultured equine fibroblast-like synoviocytes exposed to lipopolysaccharide (LPS), fibrinogen and thrombin. Synovial membranes were collected from metacarpo-phalangeal joints of 6 skeletally mature horses euthanized for non-orthopaedic reasons. Passage 4 fibroblast-like synoviocytes were left non-treated or treated with either 0.1 μg/ml LPS, 5 mg/ml fibrinogen or 5 U...
Marfe G, Massaro-Giordano M, Ranalli M, Cozzoli E, Di Stefano C, Malafoglia V, Polettini M, Gambacurta A.Stem cell technology has evoked considerable excitement among people interested in the welfare of animals, as it has suggested the potential availability of new tools for several pathologies, including eye disease, which in many cases is considered incurable. One such example is ulcerative keratitis, which is very frequent in horses. Because some of these corneal ulcers can be very severe, progress rapidly and, therefore, can be a possible cause of vision loss, it is important to diagnose them at an early stage and administer an appropriate treatment, which can be medical, surgical, or a combi...
Viitanen M, Bird J, Smith R, Tulamo RM, May SA.The study hypothesis was that navicular disease is a process analogous to degenerative joint disease, which leads to changes in navicular fibrocartilage and in deep digital flexor tendon (DDFT) matrix composition and that the process extends to the adjacent distal interphalangeal joint. The objectives were to compare the biochemical composition of the navicular articular and palmar cartilages from 18 horses with navicular disease with 49 horses with no history of front limb lameness, and to compare navicular fibrocartilage with medial meniscus of the stifle and collateral cartilage of the hoof...
Milam SB, Mackay RJ, Skelley LA.Secretion of tumor necrosis factor (TNF) by equine mammary exudate macrophages (MEM phi) exposed to bacterial lipopolysaccharide (LPS) was dose-dependent and was maximal (216.5 +/- 51.9 U/ml) at 100 micrograms LPS/ml, the highest concentration tested. All concentrations of dexamethasone tested (10(-8) to 10(-4) M) significantly (P less than or equal to 0.05) inhibited TNF production by MEM phi when the agent was added 1 hour before LPS. Pretreatment with pentoxifylline at concentrations greater than 3 micrograms/ml also significantly (P less than or equal to 0.05) reduced secretion of TNF by M...
Black JB, Frampton AR.Equine herpesvirus type 1 (EHV-1) is a highly transmissible pathogen that leads to a variety of clinical disease outcomes in infected horses. A major sequela that can occur after an EHV-1 infection is a neurological disease termed equine herpesvirus myeloencephalopathy (EHM). Clinical manifestations of EHM include fever, ataxia, incontinence, and partial to full paralysis, which may ultimately lead to the euthanization of the infected horse. To develop an effective treatment strategy for EHM, it is critical that the specific virus-host interactions that lead to EHM be investigated so that safe...
Gehlen H, Ohnesorge B.To describe removal of guttural pouch chondroids through a laser fenestrated mesial septum in a pony with an obstructed pharyngeal ostium of the left guttural pouch. Methods: Case report. Methods: Pony. Methods: Transendoscopic laser neodymium:yttrium aluminum garnet (Nd:YAG) fenestration of the mesial guttural pouch septum was made by contact method (bare fiber, 15-25 W, exposure time 4 seconds). Dissected tissue was removed by transendoscopic monopolar electrosurgery (loop electrode, cutting blade) and multiple chondroids of varying size were removed from the left guttural pouch through the ...
Ekman S, Skiöldebrand E, Heinegård D, Hultenby K.One of the most common causes of lameness in racehorses is osteoarthritis (OA). Pathogenesis is not clear and pathological processes of the different joint tissues interact in often progressive events. The interface between cartilage and newly synthesised bone has been shown to be particularly enriched in bone sialoprotein (BSP), a cell-binding matrix protein. Objective: To establish whether changes in the concentration of BSP may serve as a marker for early biochemical changes of the subchondral bone. Methods: Articular cartilage, cartilage/bone interface and subchondral bone of the proximal ...
Silveira A, Koenig JB, Arroyo LG, Trout D, Moens NM, LaMarre J, Brooks A.To determine effects of extracorporeal shock wave therapy (ESWT) on healing of wounds in the distal portion of the forelimb in horses. Methods: 6 horses. Methods: Five 6.25-cm2 superficial wounds were created over both third metacarpi of 6 horses. Forelimbs were randomly assigned to treatment (ESWT and bandage) or control (bandage only) groups. In treated limbs, each wound was treated with 625 shock wave pulses from an unfocused electrohydraulic shock wave generator. In control limbs, each wound received sham treatment. Wound appearance was recorded weekly as inflamed or healthy and scored for...
Haerdi-Landerer MC, Suter MM, Steiner A, Wittenbrink MM, Pickl A, Gander BA.For the treatment of septic arthritis in large animals, the local application of antibiotics as a slow release system may be an appropriate means to reach high local bioactivity and low systemic side effects and drug residues. In this study, doxycycline microspheres were developed and tested in vitro for their drug-release properties, suitability for intra-articular application and antimicrobial activity. Methods: The development of a slow release system was achieved by microencapsulation of the drug into poly(lactide-co-glycolide) microspheres by a novel ultrasonic atomization method. Drug el...
Azimpour S, Emami Alagha H, Faghihi H, Rajaei SM, Shokoohimand A.The purpose of this study was to determine the effects and potential side effects of topical preservative-free (PF) tafluprost 0.0015% in ophthalmologically normal horses. Methods: Five adult grade horses. Methods: One of the eyes of each horse was randomly chosen as the "treatment" eye, and consequently, the contralateral eye served as the "control." A single dose of PF tafluprost 0.0015% (0.2 mL) was instilled in the treated eye of each horse. Intraocular pressure (IOP), Schirmer's tear test (STT) levels of each eye, and an ophthalmic examination were performed at T0 (baseline), T30, T120, ...
Morris DD, Henry MM, Moore JN, Fischer K.In laboratory animals, the incorporation of alpha linolenic acid or other n-3 series fatty acids into the diet results in marked changes in cell membrane composition as well as arachidonic acid metabolism. The purpose of the present study was to determine whether endotoxin-induced thromboxane A2 (TxA2) and/or prostacyclin (PGI2) production by equine peritoneal macrophages was altered by feeding horses a diet containing 8% linseed oil as a source of alpha linolenic acid for 8 weeks. Peritoneal macrophages were cultured in vitro in the presence of endotoxin (LPS) (0.5-500 ng/ml) or calcium ionop...
Heuerman J, Haiub H, Cull E, Lupatini R, Shrum B, Sidhu R.In this case report, we highlight the benefits of Medisca CopaSil application for scar healing in a horse having sustained second-degree burn injuries covering most of its back. The application of CopaSil started three months after sustaining the burn injury when silver sulfadiazine topical cream treatment showed no significant improvement. CopaSil is formulated with ingredients that may help in reducing inflammation and accelerate healing by modulating the immune response. After using CopaSil for six months, the horse's back was healed, and the hair began to regrow. The complete healing...
Specht TE, Nixon AJ, Colahan PT, Moore BG, Brown MP.Four horses with subchondral cyst-like lesions in the medial radial facet of the distal portion of the radius were examined. Joint effusion and signs of pain from flexion of the antebrachiocarpal joint were not observed, but lameness was observed in 3 of the 4 horses. Regional nerve blocks and intra-articular anesthesia were used to localize the lesions, and conservative treatment resulted in soundness for performance.
Bowker RM, Sonea IM, Vex KB, Caron JP.Substance P (SP) immunocytochemistry and receptor autoradiography were used to define the innervation of the equine synovial membrane of joints equivalent to the wrist and knuckle of man. SP-immunoreactive fibers were mainly concentrated around blood vessels in the subsynovial layer, although not exclusively, while in the more distal joint, SP fibers were more frequently seen in the synovial surface layer. Iodinated SP receptor autoradiography studies revealed silver grain concentrations in the advential layer of blood vessels associated with the vasa vasorum, on the vascular endothelium and i...
Ablett JM, Fairbairn SM, Page CP, Lees P, Cunningham FM.A role for platelets in allergic airways disease has been postulated and changes in the responsiveness of circulating platelets have been demonstrated following antigen challenge of asthmatic human subjects. In this study agonist-induced aggregation of equine platelets in vitro has been compared before and after exposure of horses to a controlled hay and stray challenge. Prior to challenge the response of platelets, from horses with chronic obstructive pulmonary disease (COPD) and normal animals, to adenosine diphosphate (ADP) and platelet activating factor (PAF) did not differ. Five hours aft...
Boyd EH, Allen WE.Plasma drug concentrations were measured after two commercially available potentiated sulphonamides, trimethoprim and sulfadoxine and trimethoprim and sulphadiazine, were infused daily for 2 and 3 days, respectively, into the uteri of pony mares which had been mated before ovulation. Intravenous administration of trimethoprim and sulfadoxine allowed uterine absorption of trimethoprim (23-43%) and sulfadoxine (29-34%) to be calculated. After intra-uterine administration trimethoprim and sulphadiazine were detected in the milk of a lactating mare. In order to maintain plasma concentrations likel...
Meijer AE, van den Hoven R, Wensing T, Breukink HJ.Needle biopsies from m. gluteus medius of 22 horses which had suffered from repeated attacks of exertional myopathy were studied at various times after an attack, to determine if metabolic alterations can be demonstrated by enzyme histochemistry. Morphological changes and activity of 25 enzymes were studied. Immediately after onset of an attack, some large rounded fibres with a defect of the oxidative phosphorylation were seen. After some hours these fibres lost their glycolytic enzyme activity, followed by disappearance of mitochondrial enzyme activity with accumulation of Ca2+-containing sub...
Klein V, Müller K, Schoon HA, Reilas T, Rivera del Alamo MM, Katila T.Oestrous suppression by intrauterine devices (IUDs) is caused by prolongation of luteal function, but the biological mechanism is unknown. The aim of the study was to investigate mechanisms which could explain the action of IUDs. Thirty mares were age-matched and either inseminated (AI, n = 15) or fitted with an IUD (IUD, n = 15) and subsequently divided into four groups: AI-P, pregnant (n = 8); AI-N, non-pregnant (n = 7); IUD-P, prolonged luteal phase (n = 7); and IUD-N, normal luteal phase (n = 8). The median ages were 5.5 and 7 years in AI-P and IUD-P groups and 14 and 11 years in AI-N and ...
