The skin of horses is a complex organ that serves multiple functions, including protection, thermoregulation, and sensory perception. It consists of several layers, primarily the epidermis and dermis, each contributing to the overall health and functionality of the skin. The epidermis provides a barrier against environmental factors, while the dermis supports the skin structure and houses blood vessels, nerves, and hair follicles. Equine skin is also involved in the production of sweat and sebum, which aid in temperature regulation and skin lubrication, respectively. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, physiology, and health conditions of equine skin, as well as advancements in dermatological treatments and care practices.
Martano M, Corteggio A, Restucci B, De Biase ME, Borzacchiello G, Maiolino P.Equine sarcoids are locally invasive, fibroblastic benign skin tumors. Bovine papillomavirus type-1 (BPV-1) and/or Bovine papillomavirus type-2 (BPV-2) are believed to be the causative agent of sarcoids, although the mechanisms by which the virus induce the tumor are still poorly understood. We hypothesized that in genetically predisposed equines latent BPV infection may be reactivated by immunosoppression and/or mechanical injury leading to a form of pathologic wound which may transform into a sarcoid. In this study, we investigated in 25 equine sarcoids and in five normal skin samples the hi...
Bischofberger AS, Dart CM, Horadagoda N, Perkins NR, Jeffcott LB, Little CB, Dart AJ.To investigate the effect of 66% Manuka honey gel on the concentrations of transforming growth factor (TGF)-β1 and TGF-β3, bacterial counts and histomorphology during healing of contaminated equine distal limb wounds. Methods: In this experimental study of 10 Standardbred horses, five full-thickness skin wounds (2 × 1.5 cm) were created on one metacarpus and six similar wounds were created on the contralateral metacarpus. Wounds were assigned to three groups: non-contaminated control wounds; contaminated control wounds; contaminated wounds treated daily with 1 mL Manuka honey gel to...
Federici M, Gerber V, Doherr MG, Klopfenstein S, Burger D.In the last 30 years the amount of white markings in the population of Franches-Montagnes horses (FM) has more than doubled which has led to some controversy, particularly in respect to the health of the horses. The objective of this study was to investigate if the coat colour and white markings have an impact on selected skin diseases and hoof horn abnormalities. To this purpose 974 three-year-old FM were subjected to a clinical examination during the field and station tests organized by the FM breeding association. In 16.9% of the horses, one or several equine sarcoids were detected, 15.2% o...
Shokri H.The aim of this study was to investigate the prevalence of Malassezia species from the body skin and external ear canal of healthy horses. The samples were obtained by scraping the skin surface from the nose, groin and dorsum and swabbing from the external ear canal of 163 animals, and then incubated on sabouraud dextrose agar and modified Dixon agar. Malassezia species were isolated from 34.9% of horses. The percentages of Malassezia species were 64.3% for Arab, 35.7% for Persian, 35.4% for Thoroughbred and 27.1% for Turkmen breeds. The greatest abundance of Malassezia species was found in th...
Bischofberger AS, Tsang AS, Horadagoda N, Dart CM, Perkins NR, Jeffcott LB, Jackson CJ, Dart AJ.To investigate the effect of activated protein C (APC) on second intention healing of distal limb wounds in horses. Methods: In this experimental study of eight Standardbred geldings, six full-thickness skin wounds (2 × 1.5 cm) were created on one metacarpus (biopsy limb) and five similar wounds were created on the contralateral metacarpus (photographed limb). Three wounds on the biopsy limb were treated topically with 190 µg APC on days 1, 3, 6 and 9, while the remaining three wounds were untreated (control). One treated and one control wound were biopsied on days 4, 7 and 11 for hi...
Vyas R, Keller JJ, Honda K, Cooper KD, Gerstenblith MR.Animal-type melanoma is a rare subtype of melanoma with heavily pigmented dermal epithelioid and spindled melanocytes. Its classification as a subtype of melanoma versus a borderline melanocytic tumor is debated. Objective: Our primary objective was to characterize the demographics, clinical presentation, histopathology, management, and outcomes of patients with animal-type melanoma. Methods: We performed a systematic review and meta-analysis of the English-language literature on animal-type melanoma. Results: We identified 190 cases of animal-type melanoma. They occurred equally in men and wo...
Rashmir-Raven A, Lavagnino M, Sedlak A, Gardner K, Arnoczky S.Hereditary equine regional dermal asthenia (HERDA) is a genetic disorder of collagen resulting in fragile, hyper-extensible skin and ulcerative lesions. The predominance of skin lesions have been shown to occur on the dorsum of HERDA-affected horses. While this has been postulated to be due to increased exposure to sunlight of these areas, the precise pathological mechanism which causes this to occur is unclear. Objective: We hypothesized that an increase in collagenase activity, that has been associated with the exposure of dermal fibroblasts to sunlight, will significantly degrade the materi...
Meulenbroeks C, van der Meide NM, Willemse T, Rutten VP, Tijhaar E.Ponies may suffer from Insect bite hypersensitivity (IBH), an allergic IgE-mediated pruritic skin disorder, induced by allergens from biting midges of the Culicoides spp. Objective: To determine whether recombinant Culicoides obsoletus allergens are able to activate T cells of ponies exposed to C. obsoletus and whether these allergen-specific responses differ between IBH-affected and healthy ponies. Methods: Ten IBH-affected Shetland ponies and 10 age-matched healthy controls taken from the same stables, to ensure similar exposure to midges. Methods: Peripheral blood mononuclear cells (PBMC) w...
Ressel L, Ward S, Kipar A.Equine cutaneous mast cell tumours (CMCTs) are generally considered to be benign skin lesions, although recurrent and multicentric tumours have been described. For canine CMCTs, grading and prognostic approaches are well established and aberrant KIT expression as well as high proliferation indices are associated with poor outcome. However, in the case of equine CMCTs, morphological features, proliferative activity and KIT expression pattern have not been assessed or related to biological behaviour, and there is discussion as to whether CMCTs are true neoplastic processes. The present study des...
Moghtaderi M, Farjadian S, Hosseini Z, Raayat A.The aim of this study has been to investigate the frequency of sensitization to horse allergens and clinical symptoms in horse riders. Methods: A total of 42 horse riders and 50 healthy individuals were examined by means of skin prick tests for a panel of horse and common animal allergens, and pulmonary function tests were done by spirometry. Results: The rate of sensitization to horse allergens was 31% as proven by the skin prick test in horse riders whereas horse sensitization was not seen in the control group. Occupational allergy symptoms were reported by 19 horse riders. Two horse riders ...
de Souza MV, Silva MB, Pinto Jde O, Lima MB, Crepaldi J, Lopes GF, dos Santos HB, Ribeiro RI, Thomé RG.This study evaluated the immunohistochemical expression of type I (COL I) and III (COL III) collagens during the healing process of skin treated with leukocyte-poor platelet-rich plasma (LP-PRP). Seven healthy gelding crossbred horses aged 16 to 17 years were used. Two rectangle-shaped wounds were created surgically in the right and left gluteal regions. Twelve hours after wound induction, 0.5 mL of the LP-PRP was administered in each edge of the wounds of one of the gluteal regions. The contralateral region was used as control (CG). Three samples were obtained: after wound induction (T0), 1...
Wobeser BK.Skin disease in horses is a common and potentially challenging clinical problem. Information pertaining to skin disease is lacking in horses when compared with that in other companion animal species. Certainly, both horse-specific and location-specific patterns are present, but these can often be confounded by other factors. There are many possible ways in which to organize skin disease; in this article, they are organized based loosely on their most common clinical feature. Space limits the number of conditions that can be described here, and those chosen were seen relatively frequently in a ...
Aguiar C, Therrien J, Lemire P, Segura M, Smith LC, Theoret CL.Skin trauma in horses often leads to the development of chronic nonhealing wounds that lack a keratinocyte cover, vital for healing. Reports in mouse and man confirm the possibility of generating functional keratinocytes from induced pluripotent stem cells (iPSC), thus presenting myriad potential applications for wound management or treatment of skin disease. Similarly, differentiation of equine iPSC (eiPSC) into a keratinocyte lineage should provide opportunities for the advancement of veterinary regenerative medicine. Objective: The purpose of this study was to develop an efficient method fo...
Johnson J, Messier S, Meulyzer M, Vinardell T, Marcoux M, David F.To compare bacterial colonization after diluted iodine tincture or povidone iodine solution for presurgical disinfection of the equine peripodal region. Methods: Complete block design. Methods: Five horses. Methods: Disinfection protocols using iodine tincture or povidone iodine solutions were tested on 5 pairs (n = 10) equine front feet. Iodine tincture was applied to the left feet and povidone iodine to the right feet. Fixed surfaces of the sole, frog, hoof wall, and peripodal skin were swabbed pre-preparation (T0), after a standard pre-disinfection step (T1), after short disinfection wi...
Linardi RL, Megee SO, Mainardi SR, Senoo M, Galantino-Homer HL.The limited characterization of equine skin, eye and hoof epithelial stem cell (ESC) and differentiation markers impedes the investigation of the physiology and pathophysiology of these tissues. Objective: To characterize ESC and differentiation marker expression in epithelial tissues of the equine eye, haired skin and hoof capsule. Methods: Indirect immunofluorescence microscopy and immunoblotting were used to detect expression and tissue localization of keratin (K) isoforms K3, K10, K14 and K124, the transcription factor p63 (a marker of ESCs) and phosphorylated p63 [pp63; a marker of ESC tr...
Davids BI, Davidson MJ, TenBroeck SH, Colahan PT, Oli MW.To compare the efficacy of sterile preoperative skin antisepsis using either a 5-minute mechanical preparation or 5-minute non-mechanical preparation with chlorhexidine gluconate 4% solution. Methods: Matched design, ANOVA. Methods: Healthy adult Thoroughbred horses (n = 30). Methods: Each horse had both surgical preparation methods randomly assigned to identical sites on the left or right upper thigh. Prepared sites were sampled and cultured for bacteria after each preparation step. Results: Mechanical and non-mechanical preparation techniques significantly reduced bacteria isolated from ...
Bussche L, Harman RM, Syracuse BA, Plante EL, Lu YC, Curtis TM, Ma M, Van de Walle GR.The prevalence of impaired cutaneous wound healing is high and treatment is difficult and often ineffective, leading to negative social and economic impacts for our society. Innovative treatments to improve cutaneous wound healing by promoting complete tissue regeneration are therefore urgently needed. Mesenchymal stromal cells (MSCs) have been reported to provide paracrine signals that promote wound healing, but (i) how they exert their effects on target cells is unclear and (ii) a suitable delivery system to supply these MSC-derived secreted factors in a controlled and safe way is unavailabl...
Jensen-Jarolim E, Einhorn L, Herrmann I, Thalhammer JG, Panakova L.Both humans and their most important domestic animals harbor IgE and a similar IgE receptor repertoire and expression pattern. The same cell types are also involved in the triggering or regulation of allergies, such as mast cells, eosinophils or T-regulatory cells. Translational clinical studies in domestic animals could therefore help cure animal allergies and at the same time gather knowledge relevant to human patients. Dogs, cats and horses may spontaneously and to different extents develop immediate type symptoms to pollen allergens. The skin, nasal and bronchial reactions, as well as chro...
Cappelli K, Brachelente C, Passamonti F, Flati A, Silvestrelli M, Capomaccio S.Epitheliogenesis imperfecta in horses was first recognized at the beginning of the 20th century when it was proposed that the disease could have a genetic cause and an autosomal recessive inheritance pattern. Electron microscopy studies confirmed that the lesions were characterized by a defect in the lamina propria and the disease was therefore reclassified as epidermolysis bullosa. Molecular studies targeted two mutations affecting genes involved in dermal-epidermal junction: an insertion in LAMC2 in Belgians and other draft breeds and one large deletion in LAMA3 in American Saddlebred. Metho...
Monthoux C, de Brot S, Jackson M, Bleul U, Walter J.Skin malformations that resembled manifestations of Ehlers-Danlos-Syndrome were described in a variety of domestic animals during the last century as cutis hyperelastica, hyperelastosis cutis, dermatosparaxis, dermal/collagen dysplasia, dermal/cutaneous asthenia or Ehlers-Danlos-like syndrome/s. In 2007, the mutation responsible for Hereditary Equine Regional Dermal Asthenia (HERDA) in Quarter Horses was discovered. Several case reports are available for similar malformations in other breeds than Quarter Horses (Draught Horses, Arabians, and Thoroughbreds) including four case reports for Warmb...
Miragliotta V, Pirone A, Donadio E, Abramo F, Ricciardi MP, Theoret CL.Convincing evidence shows that persistent or excessive expression of osteopontin (OPN) is linked to fibroproliferation of various organs in laboratory animals and in man, such that its downregulation is a logical therapeutic objective. Objective: To investigate OPN expression in an equine model of wound healing and in clinical specimens of equine exuberant granulation tissue and human keloids in an effort to better understand the contribution of this protein to inflammation-associated skin fibrosis. Methods: Description of gene and protein expression in an experimental equine model of wound he...
Jiang L, Campagne C, Sundström E, Sousa P, Imran S, Seltenhammer M, Pielberg G, Olsson MJ, Egidy G, Andersson L, Golovko A.Constitutive activation of the ERK pathway, occurring in the vast majority of melanocytic neoplasms, has a pivotal role in melanoma development. Different mechanisms underlie this activation in different tumour settings. The Grey phenotype in horses, caused by a 4.6 kb duplication in intron 6 of Syntaxin 17 (STX17), is associated with a very high incidence of cutaneous melanoma, but the molecular mechanism behind the melanomagenesis remains unknown. Here, we investigated the involvement of the ERK pathway in melanoma development in Grey horses. Methods: Grey horse melanoma tumours, cell lines ...
Borena BM, Meyer E, Chiers K, Martens A, Demeyere K, Broeckx SY, Duchateau L, Spaas JH.Mammal skin plays a pivotal role in several life preserving processes and extensive damage may therefore be life threatening. Physiological skin regeneration is achieved through ongoing somatic stem cell differentiation within the epidermis and the hair follicle. However, in severe pathological cases, such as burn wounds, chronic wounds, and ulcers, the endogenous repair mechanisms might be insufficient. For this reason, exogenous purification and multiplication of epithelial-like stem/progenitor cells (EpSCs) might be useful in the treatment of these skin diseases. However, only few reports a...
Mosseri S, Hetzel U, Hahn S, Michaloupoulou E, Sallabank HC, Knottenbelt DC, Kipar A.Sarcoids are the most prevalent equine skin tumours and remain a therapeutic challenge due to their differing clinical morphology, local aggressive behaviour, and high recurrence following surgical treatment. In vitro, sarcoid derived fibroblasts are invasive and express matrix metalloproteinase (MMP) -1, -2 and -9. It was hypothesised that the MMPs produced by neoplastic cells play a role in both their local invasiveness and interaction with the overlying epidermis (picket fence formation). The objective of this morphological study was to investigate the local behaviour and in situ MMP expres...
Yarnell K, Fleming J, Stratton TD, Brassington R.Infrared thermography (IRT) was used to assess surface temperature change as an indirect measure of muscle activity and exercise associated changes in blood flow in the working hind limb muscles of horses (n=7) undergoing water treadmill exercise. Three treatments were investigated including the treadmill ran dry (TD), water at the height of the proximal interphalangeal joint (PIP) and water at the height of the carpus (CP). Maximum skin surface temperature was recorded from the region of the semitendinosus muscle during exercise at each water height. There was a significant difference in surf...
Cerrato S, Ramió-Lluch L, Brazís P, Rabanal RM, Fondevila D, Puigdemont A.There is increasing interest in the biological and pathological study of equine skin owing to the high prevalence of cutaneous diseases in horses. However, knowledge of equine skin cell biology and cultures is limited by the low number of in vitro studies in the literature. Objective: The objective of the study was to develop and characterize an in vitro equine skin equivalent. Methods: Cultures of pure equine keratinocytes and dermal fibroblasts were obtained by enzymatic digestion of skin biopsies. Fibroblasts were embedded into type I collagen matrices to obtain dermal scaffolds, the surfac...
Hillyer LL, Jackson AP, Quinn GC, Day MJ.Epidermal (infundibular) and dermoid cysts are unusual in the horse in contrast with other species. The diagnosis and treatment of six lesions in the dorsal midline of a three-year-old Thoroughbred-cross gelding is described. The lesions were believed to be congenital and presented asymptomatically but required attention because five of them were in the saddle region, thus preventing ridden exercise. Under general anaesthesia, the cysts were excised and subsequently examined histologically. The horse recovered uneventfully. This report is novel in that such midline cysts have not previously be...
O'Niell FD, Issel CJ, Henk WG.Organ cultures of equine fetal tracheal and nasal turbinate epithelium were inoculated with equine influenza virus-A1 (EIV-A1), equine herpesvirus-1 (EHV-1), or equine rhinovirus-1 (ERV-1). Infected organ cultures were processed for scanning and transmission electron microscopy at various intervals and were compared with noninfected controls. Organ cultures inoculated with ERV-1 appeared normal with the exception of rare island-like lesions in infected nasal turbinate. Virus particles were not seen in thin sections of organ cultures infected with ERV-1. The EHV-1 caused extensive loss of the e...
Rashmir-Raven A.Hereditary equine regional dermal asthenia is a form of Ehlers-Danlos syndrome, and has an autosomal recessive mode of inheritance. Affected horses are typically born normal and develop lesions within the first 2 years of life. The most common symptoms of the disease include stretchy, loose skin that feels doughy or mushy. More severely affected horses experience spontaneous skin sloughing and extensive lacerations, hematomas, and seromas from minor trauma. Affected horses have a higher than expected incidence of corneal ulcers. DNA testing can normal, establish carrier and affected status. Pa...
Hollis AR.Sarcoids are the most common cutaneous neoplasm of the horse, arising as a result of a neoplastic proliferation of fibroblasts associated with infection with bovine papillomavirus, most notably types 1 and 2. Although they do not metastasise, they are locally invasive and aggressive, and can lead to important welfare concerns, interfere with tack and therefore impede athleticism, and undoubtedly lead to a reduction in the value of affected horses. This review discusses the evidence behind the most commonly used treatments for equine sarcoids. The most commonly used treatments are discussed. No...
Knottenbelt DC.Skin disease in donkeys is less common than in horses, but is easily overlooked. Little published material exists on this important area of equine medicine. Skin tumors continue to challenge veterinarians working with donkeys. This article outlines the main disease entities that the author has encountered, although there are many other diseases and disorders that occur in different parts of the world that are not yet appreciated. When investigating a skin disease, a logical and comprehensive clinical approach should always be made; many conditions are similar in clinical presentation or are co...
Michanek P, Toth T, Bergström E, Treffenberg-Pettersson H, Bergh A.Light-emitting diodes (LEDs) are commonly used for treating a variety of disorders in horses, including wounds. Despite its claim to shorten healing times, there is a lack of scientific documentation regarding its effects. Objective: To investigate if treatment with pulsating visible red light (λ ≈ 637 nm) and near-infrared (NIR) light (λ ≈ 956 nm) affects wound healing. Methods: Randomised blinded controlled experimental study. Methods: A circular skin wound (Ø = 2 cm) was created on each side of the neck in eight healthy horses. One randomly chosen wound received light treatm...
Di Francesco P, Cajon P, Desterke C, Perron Lepage MF, Lataillade JJ, Kadri T, Lepage OM.To assess the clinical value and safety of the application of allogeneic equine oral mucosa mesenchymal stromal cells (OM-MSCs) to wounds. Animals. 8 healthy adult horses without front limb skin lesions or musculoskeletal disease. Procedures. Stem cells were isolated from the oral mucosa of a donor horse. Horses were subjected to the creation of eight full-thickness cutaneous wounds, two on each distal forelimb (FL) and two on both sides of the thorax (TH). Each wound was subjected to one out of four treatments: no medication (T1), hyaluronic acid- (HA-) gel containing OM-MSC (T2), HA-gel cont...
Gerber V, Kaiser-Thom S, Oesch S.Equine pastern dermatitis (EPD) is a nonspecific cutaneous reaction pattern on the distal extremities, typically in the palmar/plantar area of the pastern. Although EPD is commonly seen in equine practice and can be a debilitating condition, peer-reviewed original studies on many aspects of this multifactorial syndrome are still scarce. This narrative review aims to give an overview of the clinical presentation (forms of EPD and clinical scores and differential diagnoses), risk factors, and therapeutic approaches. The emphasis is on intrinsic and extrinsic risk factors as most of the original ...
Yasui T, Fukui K, Nara T, Habata I, Meyer W, Tsukise A.The present study revealed in detail the subcellular localization of lysozyme and beta-defensin in the apocrine glands of the equine scrotal skin, a specific body region. The apocrine glandular cells were equipped with a varying number of secretory granules, a well-developed Golgi apparatus and abundant cisternae of the rough endoplasmic reticulum within their cytoplasm. In these cells, reactive gold particles representing lysozyme were detectable in the secretory granules as well as the Golgi apparatus and elements of the rough endoplasmic reticulum. Additionally, the antimicrobial peptide gr...
Lomas HR, Robinson PA.Equine insect bite hypersensitivity (IBH), commonly known as sweet itch or summer eczema, is a frustrating recurrent skin disease in the equine industry involving an immune reaction to the bites of spp. midges. To investigate the impact of IBH in the field, an exploratory pilot study was conducted with equine stakeholders in one region of central England. Nine semi-structured, face-to-face interviews were conducted with horse owners and an equine veterinarian. The aim was to gain an understanding of experiences with IBH, and to gauge opinions on the value of the various management strategies ...
Bell NJ, Thomas S.An aged female donkey developed a severe, localised, suppurative panniculitis secondary to a skin wound. Bacterial culture of swabs taken from the wound gave a profuse growth of multi-drug-resistant Pseudomonas aeruginosa, a profuse growth of Escherichia coli and a moderate growth of beta-haemolytic Streptococcus species. The lesion did not respond to conventional medical and surgical treatment and continued to progress. Six applications of sterile larvae (maggots) of the common greenbottle, Lucilia sericata, were used to debride the wound successfully.
Fritsche A, Mathis GA, Althaus FR.Biotin deficiency in animals causes pathological changes of the skin and its appendages including, for example, exfoliative dermatitis, depigmentation, and alopecia. The hooves of biotin-deficient swine are weak, brittle, and often necrotic. These changes disappear after dietary biotin supplementation. Biotin supplementation also noticeably improves the hoof quality of horses, cattle and swine having no apparent biotin deficiency. In order to elucidate the molecular basis of these effects, the influence of biotin on cytokeratin expression in a keratinocyte cell line (Ha-CaT) was investigated u...
Johnson PJ, Ganjam VK, Slight SH, Kreeger JM, Messer NT.The role of glucocorticoids (GCs) in the pathogenesis of laminitis is incompletely understood. Local tissue activity of GC is regulated by the steroid converting enzyme, 11beta-hydroxysteroid dehydrogenase-1 (11beta-HSD-1). Changes in integumentary (skin and hoof lamellar) 11beta-HSD activity occurring during laminitis could affect the extent to which GCs are involved in its development. Objective: That changes in integumentary 11beta-HSD-1 activity associated with the laminitic condition would lead to elevated local tissue levels of GCs, which could subsequently contribute, through paracrine ...
Chaffin MK, Schumacher J, Hooper N.A 5-month-old male Quarter Horse was examined because of multicentric, granulomatous, cutaneous lesions of the dorsum and prepuce. The cutaneous lesions were excised, and sodium iodide was administered orally for 2 weeks. Multicentric cutaneous pythiosis was diagnosed by histologic examination and immunoperoxidase staining of excised tissues. By 3 months after surgery, all lesions had healed.
Brounts SH, Rashmir-Raven AM, Black SS.This case report describes a distinctive deep cutaneous lesion in a 1-year-old Quarter Horse filly with hyperelastosis cutis. The horse had a typical clinical presentation of hyperelastic skin associated with a 6-month history of cutaneous wounds that developed following minor cutaneous trauma. Punch biopsies of skin from the affected horse were thinner than similar biopsies from an age- and breed-matched control. Significant microscopic lesions were not seen in cutaneous punch biopsies stained with haematoxylin and eosin and Masson's trichrome stains, but the ultrastructure of the dermis from...
Miller RI, Campbell RS.A survey of granulomatous and neoplastic diseases of the skin of horses of tropical north Queensland was carried out during the period 1970-1980. Of 338 horses affected, 46.4% suffered from equine fibrosarcoma (sarcoid), 30.2% from phycomycosis, 7.4% from squamous cell carcinoma, 6.8% from other tumours, 4.7% from cutaneous habronemiasis and 4.4% from exuberant granulation tissue. Most specimens were submitted during the first half of the year after the wet monsoonal season and significantly more diseases originated during the first quarter. There was minor variations with breed, age and sex s...
Hofberger SC, Gauff F, Thaller D, Morgan R, Keen JA, Licka TF.OBJECTIVE To identify signs of tissue-specific cortisol activity in samples of suspensory ligament (SL) and neck skin tissue from horses with and without pituitary pars intermedia dysfunction (PPID). SAMPLE Suspensory ligament and neck skin tissue samples obtained from 26 euthanized horses with and without PPID. PROCEDURES Tissue samples were collected from 12 horses with and 14 horses without PPID (controls). Two control horses had received treatment with dexamethasone; data from those horses were not used in statistical analyses. The other 12 control horses were classified as old horses (≥...
Tóth F, Schumacher J, Castro F, Perkins J.To describe and evaluate full-thickness skin grafting of equine wounds. Methods: Case series. Methods: Adult horses (n=6). Methods: A full-thickness graft was harvested from the pectoral region with the horse anesthetized or standing and sedated after local anesthetic infiltration. Grafts were attached to the cutaneous margin of the wound with staples and/or sutures if the horse was anesthetized or if the recipient site was desensitized. Cyanoacrylate glue was used to attach the grafts to the cutaneous margin of the wound of 3 horses. Medical records were reviewed for history, physical examina...
Burns RE, Pesavento PA, McElliott VR, Ortega J, Affolter VK.Three horses presented with variably painful, nonulcerated masses of the head or neck that were diagnosed as glomus tumours. Grossly, they were fleshy, pink to tan masses ranging from 0.4 to 9 cm in diameter, involving either the deep dermis and subcutis or the subcutis and underlying skeletal muscle. Microscopically, neoplastic epithelioid cells were arranged in sheets, cords and packets within lobules. The neoplastic cells frequently abutted and formed nodular bulges into large endothelium-lined vascular spaces, especially around the tumour periphery. Large nerve branches were associated wit...
Szczepanik MP, Wilkołek PM, Pluta M, Adamek ŁR, Pomorski ZJ.The purpose of this study was to evaluate transepidermal water loss, skin hydration and skin pH in normal ponies. Sixteen ponies of both sexes were examined in the study. Measurements were taken from seven different sites: the neck region, the shoulder, thorax, lumbar, inguinal, lip region and the auricle. In each of the regions transepidermal water loss (TEWL), skin hydration and skin pH were measured. For transepidermal water loss, the lowest values were observed in the lumbar region (9.71g/hm2), while the highest values were observed in the lip region (22.35 g/hm2). In the case of skin hydr...
Bosseler L, Verryken K, Bauwens C, de Vries C, Deprez P, Ducatelle R, Vandenabeele S.A 2-year-old Standardbred gelding presented with a history of fever over 1 week, anorexia and skin lesions on all four legs. The lesions were associated with severe pruritus and oedema, and there was no response to therapy. Results: The horse was in poor body condition, was lethargic and severely pruritic. Skin lesions consisted of diffuse alopecia and crusting of the distal extremities. Initially it was slightly febrile, but subsequently its temperature increased up to 40°C. Ten days after admission it developed profuse watery diarrhoea and the skin lesions progressed. Skin biopsies revealed...
Edner A, Nyman G, Essén-Gustavsson B.To compare the effects of spontaneous breathing and mechanical ventilation on haemodynamic variables, including muscle and skin perfusion measured with laser Doppler flowmetery, in horses anaesthetized with isoflurane. Methods: Prospective controlled study. Methods: Ten warm-blood trotter horses (five males, five females). Mean mass was 492 kg (range 420-584 kg) and mean age was 5 years (range 4-8 years). Methods: After pre-anaesthetic medication with detomidine (10 microg kg(-1)) anaesthesia was induced with intravenous (IV) guaifenesin and thiopental (4-5 mg kg(-1) IV) and maintained using i...
Johnson GC, Miller MA, Floss JL, Turk JR.The histologic and immunochemical characteristics of benign vascular tumors excised from the skin of seven young horses were evaluated. The patients were male horses of various breeds and were 16 months of age or younger at the time of presentation. Six tumors occurred on the extremities, and one was removed from the lip. Histologically, most tumors consisted of cellular nodules of varying compactness with few to many blood-filled lumina. Nodular growth separated preexisting adnexa and subcutaneous collagen. Some tumors contained or consisted predominantly of loosely packed arrays of ramifying...
Kolm-Stark G, Wagner R.Icelandic horses in Austria are commonly affected by an allergic inflammatory skin disease recurring during the summer seasons, which shares characteristic features with Culicoides hypersensitivity. However, the causative agents have not yet been identified. Therefore, intradermal skin testing (IDST) with a standardised extract of Culicoides variipennis and 21 other allergens relevant within Austria was performed in 81 Icelandic horses. All horses included into the study were treated regularly with ivermectin and had no history of administration of anti-inflammatory drugs. Forty-three of these...
McKelvie J, Foster AP, Cunningham FM, Hamblin AS.Circulating lymphocyte numbers are elevated in horses with the allergic skin disease sweet itch and skin lesions are typified by an infiltrate of eosinophils and mononuclear cells, the latter of which have not been fully characterised. The aim of the present study was to characterise the lymphocyte subpopulations in the circulation and skin of ponies with sweet itch by flow cytometry and a newly developed modified alkaline phosphatase immunohistochemical technique. Sweet itch ponies were found to have significantly greater numbers of circulating CD5+ and CD4+ T-lymphocytes than normal animals....
Grobbel M, Lübke-Becker A, Alesík E, Schwarz S, Wallmann J, Werckenthin C, Wieler LH.A total of 120 isolates of Klebsiella spp. and Proteus spp. collected from horses and small animals (dogs and cats) were screened for their susceptibility to 24 different antimicrobial agents. Klebsiella spp. were included from infections of the genital tract (GT) of horses (36 isolates) and the urinary/genital tract (UGT) from dogs and cats (17 isolates), while Proteus spp. were from small animal (dogs and cats) infections of the UGT (37 strains) and the skin (incl. ear/mouth) (30 isolates). In Klebsiella spp. resistance appeared most frequently to ampicillin (53-67%), sulfamethoxazole (19-29...
Zielińska P, Soroko-Dubrovina M, Dudek K, Ruzhanova-Gospodinova IS.The reason for undertaking this study was to investigate soft tissue response to high-intensity laser therapy (HILT) by measuring changes in skin surface temperature and longissimus dorsi muscle tone in the thoracolumbar back area in Thoroughbreds with back pain and diagnosed with and without Kissing Spines Syndrome (KSS). Thoroughbreds aged 3-4 years with clinically presented back pain underwent a radiological examination (to assess a lack or presence of KSS) and longissimus dorsi muscle palpation (to assess muscle tone and pain degree). The subjects were divided into two groups, those with K...
Theoret CL, Barber SM, Gordon JR.To describe the localization of immunoreactive transforming growth factor (TGF)-beta1 in both normal skin and full-thickness dermal wounds of the limb and the thorax of the horse. Methods: Six full-thickness excisional wounds were created on the lateral aspect of one metacarpal region and on the midthoracic area of each horse. Sequentially collected tissue specimens from wound margins were assessed for TGF-beta1 expression by immunohistochemistry. Methods: Four horses (2 to 4 years of age). Methods: A neutralizing monoclonal anti-human TGF-beta1 antibody was used to detect the spatial expressi...
Hamada M, Oyamada T, Yoshikawa H, Yoshikawa T, Itakura C.The histopathological development of equine cutaneous papillomas was studied in 78 warts naturally occurring in 50 one to 3-year-old Thoroughbred or Arab horses and in 54 warts experimentally induced in three 2-year-old Thoroughbreds. Lesions in the natural cases were categorized into three phases, growth, development and regression. Main lesions of the growing phase were marked hyperplasia of the basal cells and mild to moderate acanthosis, hyper- and parakeratosis with a few intranuclear inclusion bodies (IIB) which were positive with anti-bovine papillomavirus serum. In the developing phase...
Figueredo LA, Cafarchia C, Otranto D.Fungi of the genus Geotrichum are commonly found in the environment and, in some circumstances, they may cause diseases in humans and animals. Although these fungi have been isolated from skin lesions of some animal species, their pathogenic role in horses remains uncertain. With the aim to investigate the role of Geotrichum candidum as etiological agent of dermatomycoses, a retrospective study of 64 horses presenting skin lesions and suspected to have fungal infections was carried out. For each animal, anamnestic data were recorded and fungal culture were performed using hair. Out of 64 cases...
