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.
Wilmink JM, van Weeren PR.The modified Meek technique is not commonly used in equine wound management, despite the consistent reliable and superior results compared with other grafting techniques. Major drawbacks are the need for specialised, expensive equipment and general anaesthesia. Objective: To describe adjustments of the modified Meek technique enabling use in the standing horse without the need for the full equipment. This implied the use of full-thickness skin grafts manually harvested from the pectoral area and manually cut into micrografts. Graft acceptance; healing progress; and final functional and cosmeti...
Cortez JV, Hardwicke K, Grupen CG, Herrid M, Machaty Z, Vajta G.A 6-year-old mare, a valuable polo horse, died of complications following postcolic surgery. To preserve its genetics, ear skin samples were collected immediately after death and stored in an equine embryo transfer medium at 4°C for 5 days. After trypsin digestion, monolayer fibroblast cultures were established, but signs of massive bacterial infection were found in all of them. As an ultimate attempt for rescue, rigorously and repeatedly washed cells were individually cultured in all wells of four 96-well dishes. New monolayers were established from the few wells without contamination and us...
Munday JS, Lewis MC, Leyland MH.Equine sarcoids are common skin tumors that are thought to be caused by cross-species infection by bovine papillomaviruses (BPV). A 16-year-old horse developed a 1cm diameter mandibular gingival mass opposite the right second premolar tooth (406) and a 2cm diameter mass close to the commissure of the lips on the same side of the mouth. The right cheek was diffusely thickened. Histology of the smaller mass revealed a proliferation of mesenchymal cells covered by hyperplastic epithelium that formed thick rete pegs. BPV2 DNA was amplified from the mass. Although the mass had been incompletely exc...
Anbalagan E, Malathi S.The human body's largest organ is the skin which covers the entire body. The facial skin is one area of the body that needs careful handling. It can cause several facial skin diseases like acne, eczema, moles, melanoma, rosacea, and many other fungal infections. Diagnosing these diseases has been difficult due to challenges like the high cost of medical equipment and the lack of medical competence. However, various existing systems are utilized to detect the type of facial skin disease, but those approaches are time-consuming and inaccurate to detect the disease at early stages. To address var...
Verdegaal EJMM, Howarth GS, McWhorter TJ, Delesalle CJG.Hyperthermia and exertional heat illness (EHI) are performance and welfare issues for all exercising horses. Monitoring the thermoregulatory response allows for early recognition of metabolic heat accumulation during exercise and the possibility of taking prompt and effective preventative measures to avoid a further increase in core body temperature (Tc) leading to hyperthermia. Skin temperature (Tsk) monitoring is most used as a non-invasive tool to assess the thermoregulatory response pre- and post-exercise, particularly employing infrared thermographic equipment. However, only a few studies...
Virtanen J, Hautala K, Utriainen M, Dutra L, Eskola K, Airas N, Uusitalo R, Ahvenainen E, Smura T, Sironen T, Vapalahti O, Kant R, Virtala AK....Parapoxviruses (PPV) cause skin and mucous membrane lesions in several animal species, and of the five recognized PPVs, at least three are zoonotic. Equine PPV (EqPPV) is the sixth one initially described in humans in the United States and later in a severely sick horse in Finland in 2013-2015. In 2021-2022, a large-scale pustulo-vesicular pastern dermatitis outbreak occurred in horses all over Finland. This study aimed at analysing the outbreak, identifying and describing the causative agent, describing clinical signs, and searching for risk factors. EqPPV was identified as a probable causati...
Labens R, Raidal S, Borgen-Nielsen C, Pyecroft S, Pant SD, De Ridder T.Topical wound treatments rely on carrier formulations with little to no biological impact. The potential for a common vehicle, a propylene glycol (PG) gel, to affect wound healing measures including microbiota is not known. Microbiome characterization, based on next generation sequencing methods is typically performed on tissue or directly obtained wound fluid samples. The utility for primary wound dressings to characterize equine wound microbiota in the context of topical treatments is currently unknown. This investigation reports the topical effect of an 80% PG based gel on wound healing and...
Iaconisi GN, Gallo N, Caforio L, Ricci V, Fiermonte G, Della Tommasa S, Bernetti A, Dolce V, Farì G, Capobianco L.Hyaluronic acid (HA) naturally occurs as a biopolymer in the human body, primarily in connective tissues like joints and skin. Functioning as a vital element of synovial fluid, it lubricates joints, facilitating fluid movement and diminishing bone friction to protect articular well-being. Its distinctive attributes encompass notable viscosity and water retention capacities, ensuring flexibility and absorbing shock during motion. Furthermore, HA has gained significant attention for its potential benefits in various medical applications, including rehabilitation. Ongoing research explores its pr...
Lalanne C, Bonilla AG.To evaluate the feasibility and limitations associated with a minimally invasive ultrasound-assisted cutting thread technique for tenotomy of the deep digital flexor tendon (DDFT) in horses. Methods: Ex vivo study. Methods: Twenty cadaveric forelimbs. Methods: Forelimbs were placed on a jig to mimic a standing semiflexed position and the midmetacarpal region was prepared to perform tenotomy of the DDFT using a percutaneous technique with a cutting thread. For that purpose, the thread was placed percutaneously around the DDFT (first dorsally and then palmarly) with the aid of a curved 20 gauge ...
Sjöberg I, Law E, Södersten F, Höglund OV, Wattle O.A 3D printed self-locking device made of polydioxanone (PDO) was developed to facilitate a standardized ligation technique. The subcutaneous tissue reaction to the device was evaluated after implantation in ten horses of mixed age, sex and breed and compared to loops of poly(lactic-co-glycolic acid) (PLGA). In two of the horses, the implants were removed before closing the skin. The appearance of the implants and surrounding tissue was followed over time using ultrasonography. Implants were removed after 10 and 27 (± 1) days for histologic examination. Results: On macroscopic inspection at ...
Watanabe T, Tahara K, Hirano E.Placental extract has been mostly used in skin care for cosmetic purposes. However, the use of various placental extracts has been limited due to the lack of established and effective application methods. Objective: In this study, we investigated the antiwrinkle effect of a cream formulation-LNC wrinkle eye cream (LNC-EC)-containing horse placental extract as the main ingredient. Methods: A total of 24 healthy women, aged 37-54 years, with wrinkle grades 1-3, were treated with LNC-EC for 2 weeks. The cream was applied on one-half of the participants' faces, and the results were compared with t...
Daniel J, Arnold C, Winter K, Scharner D.The aim of the study was to clarify to what extent the sonographic representation of the stomach changes depending on its filling state. Methods: In a prospective controlled study, warmblood horses presented for gastroscopy were assessed sonographically. The examinations took place when the horses were fed normally (measurement 1), after 12 hours of food deprivation (measurement 2), after insufflation of air during gastroscopy (measurement 3) and after removal of air from the stomach at the end of the gastroscopy (measurement 4). The following objective parameters were recorded: Number of inte...
Brys M, Claerebout E, Chiers K.The aim of this prospective, randomized, single-blinded, and placebo-controlled clinical trial was to investigate the efficacy of a moxidectin pour-on solution for the treatment of Chorioptes bovis infestation in Belgian draft horses, and in addition, to evaluate the effect of this treatment on the clinical signs and lesions associated with chronic progressive lymphedema (CPL). Nineteen privately owned Belgian draft horses were randomly assigned to either a treatment group (moxidectin pour-on formulation, n = 10) or a placebo group (phosphate-buffered saline (PBS), n = 9). On Day 0, all 19...
Richards T, Burron S, McCorkell TC, Trevizan L, Patterson K, Minikhiem D, Ma DWL, Pearson W, Shoveller AK.Camelina oil is derived from a low-input, high-yield crop and, in comparison to many other dietary fat sources currently used in equine diets, provides a greater amount of α-linolenic acid [ALA; (n-3)], than linoleic acid [LA; (n-6)]. However, no research exists assessing the effects of feeding camelina oil to horses in contrast to other commonly used oils. The objective of this study was to compare the effect of supplementing camelina oil to that of flaxseed and canola oil supplementation, on outcomes related to skin and coat health in horses. Thirty adult horses [23 mares, 7 geldings; 14.9 ...
Grönthal TSC, Lehto AK, Aarnio SS, Eskola EK, Aimo-Koivisto EM, Karlsson T, Koskinen HI, Barkoff AM, He Q, Lienemann T, Rimhanen-Finne R, Mykkänen A.Corynebacterium diphtheriae and Corynebacterium ulcerans, when producing toxin, are the cause of diphtheria, a potentially life-threatening illness in humans. Horses (Equus ferus caballus) are known to be susceptible to infection that may manifest clinically on rare occasions. In late 2021 and early 2022, specimens from five horses suffering from pastern dermatitis were cultured at the Laboratory of Clinical Microbiology at the Faculty of Veterinary Medicine, University of Helsinki, Finland. C. diphtheriae and/or C. ulcerans were recovered from all of these. This study aimed to (1) analyse the...
Egenvall A, Clayton HM, Byström A.Horses commonly show asymmetries that manifest as left (L)-right (R) differences in vertical excursion of axial body segments. Moving on a circle confounds inherent individual asymmetries. Our goals were to evaluate individual and group asymmetry patterns and compare objective data with subjective impressions of side preference/laterality in horses walking on L and R circles. Unassigned: Fifteen horses walked on L and R circles unridden and ridden on long and short reins. Optical motion capture (150 Hz) tracked skin-fixed markers. Variables were trunk horizontal angle; neck-to-trunk angle; ver...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of an essential oil obtained from the fruit of L. (coriander oil), when used as a sensory additive in feed for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the use of coriander oil is safe up to the maximum proposed use levels of 30 mg/kg complete feed for piglets, pigs for fattening, sows, veal calves (milk replacer), cattle for fattening, sheep, goats and horses, salmonids, dogs and ornamental ...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of essential oils from fruit and stems of Mill. (bitter fennel oil and sweet fennel oil), when used as sensory additives (flavourings). For long-living and reproductive animals, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) considered of low concern the use of bitter fennel oil (with a content of estragole up to 6.1%) at the proposed use level in complete feed: 0.6 mg/kg for laying hens and rabbits, 1.0 mg/kg for sows and dairy cows, ...
Dockery A, Beasley B, Goldberg M, Aguirre G, Moorman VJ.To determine the dose effect of peri-neural liposomal bupivacaine (LB) in an induced forelimb lameness model. Methods: 12 clinically normal adult horses. Methods: A randomized cross-over design was performed with 1 limb receiving saline and the other LB: low dose (6), high dose (6). Lameness was induced in 1 forelimb using a frog-pressure model. In the lame limb, peri-neural injection of the palmar nerves at the proximal sesamoid bones was performed using saline, low dose LB (0.25 mg/kg) (LDLB), or high dose LB (0.5mg/kg) (HDLB) in random order with a 1-week washout period between treatments. ...
Auth AK, Hinnigan GJ, Smith MA, Owen KR.Low-field, magnetic resonance imaging (MRI) is an advanced imaging modality widely used to diagnose distal limb pathology in horses, but there are limited data regarding lesion distribution within the metacarpo/metatarsophalangeal joint (MCP/MTPJ) region in lame nonracehorses. The aim of this study was to describe the low-field MRI findings and lesion distribution in nonracehorses with MCP/MTPJ region pain. Clinical records from horses undergoing MRI of the MCP/MTPJ region between July 2016 and March 2023 were reviewed. Horses were included if pain causing lameness was localized to this region...
Nankervis KJ, Tranquille CA, Chojnacka K, Tacey JB, Deckers I, Newton JR, Murray RC.Water treadmill (WT) exercise may induce limb and back kinematics that meet specific training and rehabilitation goals. The study aimed to investigate the effects of walk speed, at different water depths (WDs), on limb and back kinematics of six Thoroughbreds exercising on a WT. Horses walked at 2.8/4.3/5.5/6.0 km/h (i.e. 0.8/1.2/1.5/1.7 m/s) at dry, metacarpophalangeal and carpal WD. Videography captured limb movement in the sagittal plane. Motion-capture measured thoracolumbosacral flexion-extension (FE), and lateral bend (LB) ranges of movement (ROM) using skin surface markers on the sixt...
Equine mesenchymal stem cells (MSC) of various origins have been identified in horses, including MSCs from the bone marrow and adipose tissue. However, these stem cell sources are highly invasive in sampling, which thereby limits their clinical application in equine veterinary medicine. This study presents a novel method using an air-liquid interface to isolate stem cells from the hair follicle outer root sheath of the equine forehead skin. These stem cells cultured herewith showed high proliferation and asumed MSC phenotype by expressing MSC positive biomarkers (CD29, CD44 CD90) while not e...
Monod A, Koch C, Jindra C, Haspeslagh M, Howald D, Wenker C, Gerber V, Rottenberg S, Hahn K.Equine sarcoids (EqS) are fibroblast-derived skin tumors associated with bovine papillomavirus 1 and 2 (BPV-1 and -2). Based on Southern blotting, the BPV-1 genome was not found to be integrated in the host cell genome, suggesting that EqS pathogenesis does not result from insertional mutagenesis. Hence, CRISPR/Cas9 implies an interesting tool for selectively targeting BPV-1 episomes or genetically anchored suspected host factors. To address this in a proof-of-concept study, we confirmed the exclusive episomal persistence of BPV-1 in EqS using targeted locus amplification (TLA). To investigate...
Rhiner T, Fettelschoss V, Schoster A, Birkmann K, Fettelschoss-Gabriel A.Previously, virus-like particle (VLP)-based self-vaccinations targeting interleukin (IL)-5 or IL-31 have been suggested to treat equine insect bite hypersensitivity (IBH), a seasonal recurrent allergic dermatitis in horses. The IL-5-targeting equine vaccine significantly reduced blood eosinophil counts in horses, similar to human monoclonal antibodies targeting IL-5 or the IL-5 receptor alpha (IL-5Rα). Previous studies in humans have also reported an additional effect on reduction of basophil counts. The aim of the present study was to evaluate whether an equine anti-IL-5 vaccine affected blo...
Pessoa VC, Branco-Ferreira M, Jónsdóttir S, Marti E, Tilley P.Thirty controls (C) and 30 IBH-affected (T) Lusitano horses were evaluated. T horses were included based on anamnesis and physical examination, supported by questionnaires. All horses were submitted to skin tests, Intrademal (IDT) and Skin Prick Tests (SPT), on the neck with 14 specific allergens, 13 recombinant proteins (r-proteins) from Culicoides nubeculosus (Cul n) and Culicoides obsoletus (Cul o) salivary glands and Culicoides nubeculosus Whole Body Extract (Cul n WBE). Addicionally, a cluster of six T and six C horses were also tested with Cul n 3 and Cul n 4 produced in insect cells and...
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...
Hoikhman R, Molinková D, Pillárová D, Linhart P, Kopecká A, Jahn P.Equine sarcoids (ES) are known globally as the most frequent skin tumour affecting horses. These tumours affect the horse's monetary value, they can affect the horse's welfare and can be difficult and expensive to treat. Bovine papillomavirus (BPV) is considered to be the aetiological agent of this tumour, as BPV 1, 2 and 13 have been detected in ES. This is the only known natural cross species infection by a papillomavirus. The BPV genome can be divided into two coding regions: The early region E which encodes the transforming proteins E5, E6 and E7 as well as the replication and transcriptio...
Roberts JH, Zhang J, David F, McLean A, Blumenshine K, Müller-Alander E, Halper J.Degenerative Suspensory Ligament Desmitis (DSLD) negatively impacts connective tissues in horses, which often leads to progressive chronic pain and lameness. DSLD has been shown to be a systemic disorder that affects multiple body systems, including tendons, sclerae, and the aorta. Currently, the diagnosis is confirmed by post mortem histological examination of a tendon or suspensory ligament. Histology reveals inappropriate accumulations of proteoglycans in the tendons and other tissues in DSLD-affected horses. Unfortunately, there is no reliable method to diagnose DSLD in living horses. Rece...
Harman RM, Rajesh A, Van de Walle GR.Treatment of skin wounds is a high priority in veterinary medicine because healthy uncompromised skin is essential for the well-being of horses. Stem cells and other biologic therapies offer benefits by reducing the need for surgical procedures and conventional antibiotics. Evidence from in vitro studies and small in vivo trials supports the use of equine stem cells and biologics for the treatment of acute and chronic cutaneous wounds. Larger clinical trials are warranted to better evaluate the regenerative and immunological responses to these treatments. Additionally, delivery methods and t...
Piketh G, Williams A, Schliewert EC.Electrocardiography is the method used to monitor the electrical impulses in the heart. These diagnostics are increasingly making use of smartphone-based technologies. The objective of this research was to determine whether the Alivecor KardiaMobile (ECG) smartphone-modulated electrocardiographic device, a novel ECG device, can be used to obtain reliable electrocardiogram (ECG) readings in horses. The device was initially tested in 36 Nooitgedacht pony mares to determine the best site of application, method of skin preparation, and ECG device orientation for reliable ECG tracings. Once the mos...
Wallsten H, Olsson K, Dahlborn K.Clipping the winter coat in horses is done to improve heat dissipation during exercise and make grooming easier. It is often combined with blanketing to keep the horse warm. The aims of the present study were to investigate how clipping and the use of blankets affect thermoregulation during exercise and recovery in horses. Methods: One Gotland pony, one New Forest pony, and one warm-blooded horse exercised one after the other on a 6450 m long track. The horses walked, trotted and cantered according to a predetermined scheme, which took about 50 minutes including three stops. The scheme was rep...
Kaiser-Thom S, Hilty M, Axiak S, Gerber V.Equine pastern dermatitis (EPD), a multifactorial syndrome, manifests as skin lesions of variable severity in the pastern area. Despite the widespread use of antibacterial therapy for treating this condition, little is known about the contributing bacteria. Objective: To investigate the bacterial skin microbiota in EPD-affected and unaffected (control) pasterns. Methods: Case-control study with 80 client-owned horses; each with at least one EPD-affected and one control pastern. Methods: Horses were grouped by the form of EPD (mild, exudative or proliferative), the assigned severity grade and t...
Armando F, Mecocci S, Orlandi V, Porcellato I, Cappelli K, Mechelli L, Brachelente C, Pepe M, Gialletti R, Ghelardi A, Passeri B, Razzuoli E.Equine penile squamous cell carcinoma (epSCC) is the most frequent tumor of the external male genitalia, representing 67.5% of equine genital cancers. epSCC is associated with papilloma virus (PV) infection and has been recently proposed as a model for human PV-induced squamous cell carcinomas. It has already been suggested that epSCC might undergo epithelial-to-mesenchymal transition (EMT). This work aims to investigate in detail this process and the possible role of PV oncoproteins in epSCC. For this purpose, 18 penile SCCs were retrospectively selected and tested for both EcPV2 presence and...
Heimann M, Janda J, Sigurdardottir OG, Svansson V, Klukowska J, von Tscharner C, Doherr M, Broström H, Andersson LS, Einarsson S, Marti E....Equine insect bite hypersensitivity (IBH) is a seasonally recurrent, pruritic skin disorder caused by an IgE-mediated reaction to salivary proteins of biting flies, predominantly of the genus Culicoides. The aim of this study was to define T cell subsets and cytokine profile in the skin of IBH-affected Icelandic horses with particular focus on the balance between T helper (Th) 1, Th2 and T regulatory (Treg) cells. Distribution and number of CD4+, CD8+ and Forkhead box P3 (FoxP3)+ T cells were characterized by immunohistochemical staining in lesional and non-lesional skin of moderately and seve...
Link KA, Koenig JB, Silveira A, Plattner BL, Lillie BN.To compare the effect of extracorporeal shock wave therapy (ESWT) on expression of fibroblast growth factor-7 (FGF-7), transforming growth factor-β1 (TGF-β1), insulin-like growth factor-1 (IGF-1), platelet-derived growth factor-A (PDGF), and vascular endothelial growth factor-A (VEGF) in skin with surgically created skin wounds and intact skin in horses. Methods: 14 healthy horses. Methods: 8 horses were treated with ESWT at 6 locations along the neck at 36, 24, 12, 6, 2, or 1 hour prior to collection of full-thickness biopsy specimens from each location; a control specimen was collected fro...
Faccin M, Wiener DJ, Rech RR, Santoro D, Rodrigues Hoffmann A.The skin covers the external surface of animals, and it is constantly exposed to and inhabited by different microorganisms, including bacteria. Alterations in the skin barrier allow commensal and/or pathogenic bacteria to proliferate and penetrate deep into the lower layers of the skin. Being the first barrier to the external environment, the skin is prone to injuries, allowing the penetration of microorganisms that may lead to severe deep infections. Companion animals, especially dogs, are prone to bacterial infections, often secondary to allergic dermatitis. When environmental conditions are...
Bhide M, Yilmaz Z, Golcu E, Torun S, Mikula I.The aim of the study was to determine the seroprevalence of anti-Borrelia burgdorferi antibodies in a population of Turkish dogs and horses, as well as to compare the sensitivity of novel flow-cytometry-based borreliacidal antibody test (BAT) with ELISA assay. Serum samples collected from 400 dogs and 300 horses were tested with enzyme-linked protein A/G assay (ELPAGA), using Borrelia whole cell antigens. ELPAGA test showed 93 dogs (23.2%) and 18 horses (6%) serologically positive for anti-Borrelia antibodies. In parallel testing of sera with BAT, we found 27.75% positive dogs and 6.33% positi...
Fadok VA, Greiner EC.Forty-four seasonally pruritic horses and 21 asymptomatic horses in Florida, USA, were tested for insect, grass and mould hypersensitivity by intradermal injection of allergenic extracts. The affected horses ranged in age from 10 months to over 30 years and included a variety of breeds. Affected horses reacted to varying dilutions of extracts made from Culicoides, mosquitoes, horse flies and black flies. Reactions to Culicoides were more intense than those caused by injection of antigens from other arthropods. Mild pruritus existed from the end of February until the end of June when the condit...
Martineau D, Bowser PR, Wooster G, Forney JL.Sixty-seven adult walleye fish were examined by light and transmission electron microscopy. The fish were affected by a mesenchymal tumor previously termed Walleye Dermal Sarcoma that commonly affects up to 27% of the population seasonally. Biopsies from 24 fish were collected, and complete postmortem examinations were performed on 43 fish. Grossly, the tumors had the appearance of randomly distributed, often clustered, spherical nodules, 2-5 mm in diameter with a smooth and often ulcerated surface. The tumors arose from the superficial surface of scales and consisted of fibroblast-like cells ...
Devriese LA, Nzuambe D, Godard C.One hundred and twenty eight strains of Staphylococcus from lesions, mostly of the skin, in horses were identified and compared with 29 strains isolated from the healthy skin. The pathogenic species Staphylococcus aureus, S. intermedius and S. hyicus were found almost exclusively in lesions. Other species such as S. xylosus and S. sciuri were more frequently found on the healthy skin than in lesions. The S. aureus strains formed a very heterogeneous collection. Many of these strains were staphylokinase positive and rapidly coagulated bovine plasma. Such strains are rarely found in other animal...
Van den Eede A, Hermans K, Van den Abeele A, Floré K, Dewulf J, Vanderhaeghen W, Crombé F, Butaye P, Gasthuys F, Haesebrouck F, Martens A.Given the significance of methicillin-resistant Staphylococcus aureus (MRSA) infections for both horses and staff in equine veterinary hospitals, protocols are required to minimise the risk of nosocomial transmission, including the screening of the skin and nasal chambers of equine patients for evidence of infection. The objective of this study was to clarify the potential existence and extent of MRSA on the skin of horses requiring long-term hospitalisation (≥ 6 months). Thirty such horses were sampled at eight different locations on their skin and from their nasal chambers. MRSA was isolat...
Anderson GS, Belton P, Kleider N.Six horses from British Columbia severely affected by Culicoides hypersensitivity, a seasonal dermatitis caused by the bites of Culicoides spp., were inoculated intradermally with extracts of six species or forms of Culicoides from British Columbia, United States, and Israel. Two native and four exotic species were thought to cause the disease in their own geographical area. The horses developed large welts within 20 min after injection of any of the six extracts, indicating an immediate (type I) reaction. The skin reactions caused by each extract peaked at or after 24 h, indicating an additio...
Wagner B, Childs BA, Erb HN.Skin hypersensitivity is an allergic disease induced in horses by allergens of Culicoides midges. The condition is typically diagnosed by clinical signs and in some horses in combination with allergy testing such as intradermal skin testing or serological allergen-specific IgE determination. Here, we describe an alternative method for allergy testing: a histamine release assay (HRA) that combines the functional aspects of skin testing with the convenience of submitting a blood sample. The assay is based on the principle that crosslinking of allergen-specific IgE bound via high-affinity IgE rec...
Fleury C, Bérard F, Leblond A, Faure C, Ganem N, Thomas L.An epidemiological survey was made on cutaneous melanomas occurring in Camargue-type, gray-skinned horses in southern France. The population investigated was composed of 264 horses, which were selected from the Camargue horse stud registry and were allowed to be examined by the owners. The presence of tumors was inspected macroscopically according to the standardized protocols of veterinary medicine specialists, and some tumors were subjected to macroscopic histopathological examination. The results indicated that: 1) the prevalence of melanomas in the overall population was 31.4%; 2) the odds...
Donnelly CG, Bellone RR, Hales EN, Nguyen A, Katzman SA, Dujovne GA, Knickelbein KE, Avila F, Kalbfleisch TS, Giulotto E, Kingsley NB, Tanaka J....Following the successful creation of a biobank from two adult Thoroughbred mares, this study aimed to recapitulate sample collection in two adult Thoroughbred stallions as part of the Functional Annotation of the Animal Genome (FAANG) initiative. Both stallions underwent thorough physical, lameness, neurologic, and ophthalmic (including electroretinography) examinations prior to humane euthanasia. Epididymal sperm was recovered from both stallions immediately postmortem and cryopreserved. Aseptically collected full thickness skin biopsies were used to isolate, culture and cryopreserve dermal f...
Schöniger S, Valentine BA, Fernandez CJ, Summers BA.Schwannomas are uncommonly recognized in horses. This study describes cutaneous schwannomas in 22 horses aged 8 to 25 years: 12 male, 7 female, and 3 of unknown sex. The horses had solitary cutaneous masses: 9 on the head, 3 on the neck, and the others on the shoulder, hip, thorax, abdomen, rump, extremities, or tail. The location of 1 tumor was unknown. The dermal tumors were well demarcated and expansile. Twelve had a multinodular pattern, whereas 10 formed a single nodule. Antoni A areas were observed in all tumors, and 10 tumors contained Antoni B areas. In Antoni A areas, the densely pack...
Braverman Y.Six hundred and twenty culicoides of five species were collected from a bait horse at Kannot, Israel, between April and September 1986. Seventy-two per cent of the midges were collected from the belly and 27 per cent from the dorsal aspect of the body, ie, the sweet itch summer seasonal recurrent dermatitis (SSRD) zone. Midges were active mainly from half an hour prior to half an hour after sunset. Only Culicoides puncticollis, C imicola and C schultzei group were collected in considerable numbers. While C imicola was present continuously throughout the season, the appearance of the two other ...
Murray DR, Ladds PW, Campbell RS.Lesions encountered in a clinicopathological study of cutaneous lesions resembling 'swamp cancer' from horses in North Queensland included 37 cases of subcutaneous phycomycosis, 5 of which were also infected with Habronema sp larvae. In addition 9 cases of primary cutaneous habronemiasis, 58 sarcoids, 12 fibromas, 8 fibrosarcomas, 10 squamous cell carcinomas, 4 haemangiomas, 3 melanomas, 1 papilloma, 1 palpebral adenocarcinoma and 7 cases of simple granulation were diagnosed. Subcutaneous phycomycosis resulted in the most extensive lesions. These were rapidly growing and provided the poorest p...
Geburek F, Ohnesorge B, Deegen E, Doeleke R, Hewicker-Trautwein M.We report the historical, clinical and histopathological characteristics of skin lesions in biopsies from 37 heavy draught horses with chronic pastern dermatitis. The skin lesions were divided into four macroscopic groups: scaling (group I, n=5), hyperkeratotic and hyperplastic plaque-like lesions (group II, n=14), nodular skin masses (group III, n=16) and verrucous skin lesions (group IV, n=2). The principal histological findings were hyperkeratosis and epidermal hyperplasia. There was a gradual increase in epidermal hyperplasia from groups I to IV, suggesting that the lesions represent diffe...
Galuppo LD, Pascoe JR, Jang SS, Willits NH, Greenman SL.To document natural bacterial flora on the ventral aspect of the equine abdomen, to compare 2 preparation techniques, and to identify potential risk factors that may contribute to incisional drainage. Methods: Prospective study. Methods: 53 horses undergoing exploratory celiotomy. Methods: Group-1 horses (n = 26) were prepared with povidone-iodine and alcohol. Group-2 horses (27) were prepared with a film-forming iodophor complex. Numbers of bacterial colony-forming units (CFU) were measured before and after surgical scrub, following skin closure, and after recovery from general anesthesia. Sw...
Borzacchiello G, Mogavero S, De Vita G, Roperto S, Della Salda L, Roperto F.The equine sarcoid is the most common dermatologic neoplasm reported in horses. Bovine papillomavirus (BPV) types 1 and 2 are associated with sarcoids, in which the expression of the major transforming oncoprotein (E5) is often recorded. The transformation activity of the virus is due to the binding of the E5 to the platelet-derived growth factor beta receptor (PDGFbeta-r). In the present study, we show by Western blot in 4 sarcoid samples and 3 normal equine skin samples that the PDGFbeta-r is more phosphorylated in sarcoid tissue than in normal skin (P < .001). Furthermore, the physical i...
Jose-Cunilleras E, Kohn CW, Hillier A, Saville WJ, Lorch G.To compare responses to a variety of intradermally injected allergens among healthy horses and horses with chronic obstructive pulmonary disease (COPD), recurrent urticaria (RU), and atopic dermatitis-insect hypersensitivity (allergic dermatitis [AD]). Methods: Case-control study. Methods: 86 horses. Methods: Results of intradermal testing for horses with COPD, RU, or AD were compared with results for healthy horses. Results: Compared with healthy horses, horses with COPD, RU, and AD were significantly more likely to have positive (> or = 3+) reactions to intradermal allergens (molds, weeds, t...
De Cock HE, Affolter VK, Farver TB, Van Brantegem L, Scheuch B, Ferraro GL.Chronic progressive lymphedema in Clydesdale and Shire draft horses causes severe disability of the limbs which leads to premature death of these horses. Since appropriate function of lymph vessels is dependent on the presence of viable elastin fibers, the goal of this study was to document differences in skin elastin fibers in affected horse breeds, compared to a nonaffected draft horse breed. Results: Biochemical analysis of cutaneous desmosine, a cross-linking amino acid found only in elastin, was used to measure elastin in the skin from 110 draft horses. This included 7 normal, 38 mildly a...
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...
Kupczyk P, Rykala M, Serek P, Pawlak A, Slowikowski B, Holysz M, Chodaczek G, Madej JP, Ziolkowski P, Niedzwiedz A.The endocannabinoid system (ECS) is composed of cannabinoid receptors type 1 (CBR1) and type 2 (CBR2), cannabinoid-based ligands (endogenous chemically synthesized phytocannabinoids), and endogenous enzymes controlling their concentrations. Cannabinoid receptors (CBRs) have been identified in invertebrates and in almost all vertebrate species in the central and peripheral nervous system as well as in immune cells, where they control neuroimmune homeostasis. In humans, rodents, dogs, and cats, CBRs expression has been confirmed in the skin, and their expression and tissue distribution become di...
Wilson AD, Armstrong ELR, Gofton RG, Mason J, De Toit N, Day MJ.Sarcoids are common skin tumours of horses and donkeys that are characterised by persistent proliferation of dermal fibroblasts associated with the presence of bovine papillomavirus (BPV) DNA. Some early BPV proteins have been demonstrated within sarcoids and RNA containing both early and late transcripts is present, yet it remains unclear whether late replication of BPV, culminating in the production of infectious virus particles, can occur in equids. Here we report that BPV1 RNA isolated from equine sarcoids encodes a unique deletion of four residues within the L2 protein suggesting a novel ...
van Weeren PR, van den Bogert AJ, Barneveld A.Skin displacement was investigated at 16 sites in the front and hind limbs of four Dutch Warmblood horses at the trot. For visualisation of the bone under the skin, a measuring device mounted on a Steinmann pin driven into the bone under investigation, was employed. Mean displacements ranged from 8 mm (X-displacements proximal and distal metacarpus) to 142 mm (Y-displacement caudal part of greater trochanter). When compared with previously determined skin displacement patterns at walk, mean displacements at trot were of the same magnitude whereas the shape of the time-displacement curve was di...
Goodrich L, Gerber H, Marti E, Antczak DF.Sarcoids, the most common tumor of the horse, are fibroblastic, wart-like skin lesions that show variable manifestations. They are often invasive and recurrent, although they do not fulfill all criteria of malignancy. Due to their anatomic location, these tumors can sometimes cause loss of use of the horse. There is very strong evidence that sarcoids are caused by viruses closely related or identical to bovine papilloma viruses, and genetic studies have shown associations between genes in or near the equine major histocompatibility complex (MHC) and susceptibility to sarcoid. Several types of ...
Pringle J, Roberts C, Kohl M, Lekeux P.The effects of epidermal pigmentation and hair covering on the relative transparency of various animal tissues to near infrared (NIR) light were examined, and the pathlengths of NIR light through tissues at four wavelengths in the NIR range were subsequently determined. Black hair covering and black or dark-coloured hooves prevented NIR light from penetration sufficient for conduction of pathlength or NIR spectroscopy measurements. Non-pigmented hair covering of the head did not appear to be a barrier to successful NIR light transmission. Tissues sufficiently transparent to NIR light had the d...
