Topical administration for horses refers to the application of medication or therapeutic agents directly onto the skin or mucous membranes. This method is used to deliver drugs locally to treat conditions such as skin infections, wounds, or inflammatory disorders. Common forms of topical treatments include creams, ointments, gels, and sprays. The effectiveness of topical administration depends on factors such as the drug's formulation, the condition of the skin, and the specific area being treated. This page gathers peer-reviewed research studies and scholarly articles that explore the pharmacokinetics, efficacy, and clinical applications of topical administration in equine medicine.
Poh KC, Cole ZT, Smarsh DN, Springer HR, Kelly K, Kenny LB, Machtinger ET.To evaluate the safety of repeated applications of permethrin concentrations (0% control, 1.5%, 5%, and 10%) to the necks and faces of horses and assess the efficacy and longevity of permethrin as an equine tick repellent. Methods: 5 healthy adult Quarter Horses. Methods: Each treatment was applied to the neck of each horse (0.01 m2) 4 times a day, for up to 10 days. An 8-mm biopsy was taken to evaluate postexposure dermal responses. Any treatments that were not withdrawn were applied to a quadrant of the horse's face 4 times a day, for up to 5 days. For tick bioassays, a treatment was applied...
Munday JS, Grant K, Orbell G, Vaatstra BL.A 6-year-old Thoroughbred mare developed multiple flat plaques, < 1 cm in diameter, on the left front fetlock. These were treated topically using 5-fluorouracil and resolved after 4 weeks. However, additional similar plaques developed on the left front pastern 5 months later. These lesions resolved within 3 months without treatment. Unassigned: One plaque that developed initially and one plaque that developed later were examined histologically. Both consisted of well-demarcated foci of moderate epidermal hyperplasia. Scattered throughout both plaques were cells showing evidence of papillo...
Song Y, Day CM, Afinjuomo F, Tan JE, Page SW, Garg S.While the global market for veterinary products has been expanding rapidly, there is still a lack of specialist knowledge of equine pharmaceutics. In many cases, the basic structure of the gastrointestinal tract (GIT) and integumentary system of the horse shares similarities with those of humans. Generally, the dosage form developed for humans can be repurposed to deliver equine medications; however, due to physiological variation, the therapeutic outcomes can be unpredictable. This is an area that requires more research, as there is a clear deficiency in literature precedence on drug delivery...
Helal IE, Al-Abbadi HA, El-Daharawy MH, Ahmed MF.Delayed healing associated with distal limb wounds is highly challenging in equine clinical practice. This study aimed to evaluate healing rates between chronic non-granulating wounds of horse distal limbs that were treated with maltodextrin/ascorbic acid gel alone or in combination with povidone-iodine 1% solution and those treated with povidone-iodine 1% only throughout the study period (35 days) in clinical settings. The study was conducted on 18 adult horses (3-15 years old). Based on the treatment regimen utilized, the horses were divided into three groups (n = 6), with each group having ...
Mirzaeei S, Faryadras FB, Mehrandish S, Rezaei L, Daneshgar F, Karami A.Prolonging the drug release can be a suitable approach to overcome the challenges related to topical ophthalmic administration of drugs especially the ones prescribed for chronic ailments. The sustained delivery of the drug would reduce the required frequency of administration which could extremely improve patient compliance and feeling of well-being. This study aimed to develop nanofibrous inserts for sustained ophthalmic delivery of timolol maleate (TIM) for the treatment of glaucoma. Unassigned: Polycaprolactone-based nanofibers containing TIM were prepared using pure polycaprolactone or a ...
Ekstrand C, Michanek P, Gehring R, Sundell A, Källse A, Hedeland M, Ström L.Atropine is an essential part of the treatment protocol for equine uveitis. Topical atropine administration has been associated with decreased intestinal motility and abdominal pain in horses. Experimental studies have indicated that frequent dosing is associated with a higher risk than dosing every 6 h. Unfortunately, no quantitative pharmacodynamic data for inhibition of the equine gut are published. Unassigned: Eight standardbred horses were assigned to receive either atropine or saline (control) to be infused over 30 min in a two-treatment cross-over design. Atropine concentrations in plas...
Quéré E, Chahory S.Painful eye conditions are a therapeutic challenge in horses. Subpalpebral lavage (SPL) treatment systems allow topical aqueous medications to be conveniently, safely, and frequently administered to the ocular surface. The aim of this retrospective study was to describe the outcomes and the complications associated with the location of the SPL treatment systems, in the superior or inferior eyelid in horses in a university practice. Clinical records of all horses admitted to the National Veterinary School of Alfort between January 2004 and October 2021, in which a SPL treatment system was used ...
Maldonado-Cabrera B, Sánchez-Machado DI, López-Cervantes J, Osuna-Chávez RF, Ibarra-Zazueta C, Robles-Zepeda RE.Consultation was requested for a 7-year-old Gypsy Vanner male horse with a 2-year history of foreskin injury. Upon revision, an ulcer, 153 cm2 in size, with yellowish granules was observed; a RESVECH 2.0 evaluation revealed a score of 32/35 points. Medical history confirmed multiple failed deworming, anti-inflammatory, and antibiotic treatments with different topical therapies and recurrence in summer. Laboratory results confirmed elevated total proteins (8.8 g/dL) and globulins (5.5 g/dL), negative bacterial and fungal cultures, as well as negative coproparasitoscopic findings, and finally, i...
Torcivia C, McDonnell S.Vaccinations via intramuscular injection are a key component of preventative health care in horses. Development of problematic behavioral aversion to injections is quite common. Our clinical impression has been that topical anesthetic applied to injection sites can reduce the behavioral reaction; however, this has not been critically tested. To blindly evaluate efficacy, either 5% or 10% topical lidocaine solution or 0% control was applied to injection sites for 78 ponies two minutes before intramuscular vaccination. Mean reaction scores on a scale of 0-3 were 0.84 (se 0.18) for 5% lidocaine s...
Plummer CE, Polk T, Sharma J, Bae SS, Barr O, Jones A, Kitchen H, Wilhelmy M, Devin K, Clay Smith W, Kolaczkowski BD, Larkin J.Equine recurrent uveitis (ERU) is a painful and debilitating autoimmune disease and represents the only spontaneous model of human recurrent uveitis (RU). Despite the efficacy of existing treatments, RU remains a leading cause of visual handicap in horses and humans. Cytokines, which utilize Janus kinase 2 (Jak2) for signaling, drive the inflammatory processes in ERU that promote blindness. Notably, suppressor of cytokine signaling 1 (SOCS1), which naturally limits the activation of Jak2 through binding interactions, is often deficient in autoimmune disease patients. Significantly, we previous...
Raizner NT, Gedon NKY, Zablotski Y, Kania SA, Kühnle HF, Kühnle C, Mueller RS.Equine pastern dermatitis (EPD) is a common multifactorial clinical syndrome in horses. Treatment can be difficult; pathogenesis and triggering factors cannot always be determined. Objective: To assess risk factors for developing EPD in a large group of horses kept under the same conditions and to analyse whether or not a spot-on containing essential fatty acids and antimicrobial agents is able to prevent the development of EPD or accelerate the healing process. Methods: Each year 50 young, privately owned, warmblood horses were prospectively included. Methods: All horses were examined weekly ...
Ferrari G, Pang LY, De Moliner F, Vendrell M, Reardon RJM, Higgins AJ, Chopra S, Argyle DJ.Bleomycin is a chemotherapy agent that, when administered systemically, can cause severe pulmonary toxicity. Bleosome is a novel formulation of bleomycin encapsulated in ultra-deformable (UD) liposomes that may be applicable as a topical chemotherapy for diseases such as non-melanoma skin cancer. To date, the ability of Bleosome to effectively penetrate through the skin has not been evaluated. In this study, we investigated the ability of Bleosome to penetrate through ex vivo skin explants from dogs and horses. We visualized the penetration of UD liposomes through the skin by transmission elec...
Ziadi A, Ozmaie S, Asghari A, Rajaei SM.This study aims to assess the effect of topical 0.5% apraclonidine on Intraocular pressure (IOP) in horses and compare the effects of timolol maleate 0.5% with 0.5% apraclonidine in the equine eye. Twenty healthy female thoroughbred horses were used. Horses were divided into two groups. Ten horses received single dose of 0.2 mL of 0.5% apraclonidine in one randomly selected eye and the contralateral eye received single dose of 0.2 mL of artificial tears. In the second group, 10 horses received single dose of 0.2 mL of 0.5% timolol maleate in one eye and the opposite eye received single dose of...
Lepage OM, Di Francesco P, Moulin N, Gangl M, Texier G, Marchi J, Cadoré JL.Background: The management of bleeding originating from the guttural pouch (GP) has a high success rate, but the resolution of the macroscopic inflammatory lesions in the case of mycosis (GPM) is highly variable; the resolution of neurological disorders is inconstant and challenging. Objectives: Our aim was to test the feasibility and safety of topical oxygen therapy (TOT) in horses after induction of GPM and in cases with naturally occurring disease. Study design: This study was an in vivo experimental and retrospective two-phase study. Methods: During phase 1, the pilot study, both GPs were ...
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, ...
Hermans H, van den Berg EMH, Slenter IJM, Vendrig DJC, de Nijs-Tjon LJL, Vernooij JCM, Brommer H, Boevé MH, Gehring R.Topical dexamethasone and prednisolone are currently the mainstay treatment for equine ophthalmic inflammatory diseases, such as equine recurrent uveitis. Comparative pharmacokinetic studies in horses are lacking and current guidelines are mainly based on empirical data and extrapolation from other species. Objective: To investigate the penetration and local concentrations of topically applied dexamethasone and prednisolone in normal equine ocular fluids and serum. Methods: Prospective randomised experimental pharmacokinetic study. Methods: Twenty-one Shetland ponies without ophthalmic disease...
Boss CK, Gibson DJ, Schultz G, Whitley RD, Hernandez JA, Abbott JR, Plummer CE.To investigate the therapeutic effects of topical equine amniotic membrane (eAM) suspension following corneal wounding in a controlled experimental setting. Methods: Equine amniotic membrane was collected, gamma irradiated, homogenized for topical suspension preparation, and cryopreserved. Corneoscleral rims harvested from fresh rabbit globes were wounded via keratectomy and were maintained in an air-liquid interface ex vivo corneal culture model. Treatment groups included topical gamma irradiated eAM suspension (n = 20) and a control group (n = 20). Re-epithelialization of the wound was a...
Weber LA, Delarocque J, Feige K, Kietzmann M, Kalbitz J, Meißner J, Paschke R, Cavalleri JV.The naturally occurring betulinic acid (BA) and its derivative NVX-207 induce apoptosis in equine melanoma cells in vitro. After topical application, high concentrations of the substances can be reached in healthy equine skin. With the aim to investigate the effect and safety of topically applied BA and NVX-207 in horses with melanocytic tumors, the longitudinal, prospective, randomized, double-blind, placebo-controlled study protocol included eighteen Lipizzaner mares with early-stage cutaneous melanoma assigned to three groups. Melanocytic lesions were topically treated either with a placebo...
Makra Z, Eördögh R, Fábián I, Veres-Nyéki K.To compare the corneal anaesthetic effect of 0.5% bupivacaine, 2% lidocaine and 0.4% oxybuprocaine on normal equine eyes. Methods: Prospective, blinded crossover study. Methods: A group of 10 clinically healthy horses. Methods: Corneal sensitivity was determined in each eye by measuring corneal touch threshold (CTT). The study had three phases. Each subject was randomly given one of the three treatments followed by a 72 hour washout period. Every horse received all treatments. Baseline CTT was recorded prior to anaesthetic instillation (T0) then CTT was measured 5 and 10 minutes after (T1 and ...
Hussein KH, Elmeligy E, Khalphallah A, Al-Lethie AA.This study was performed to investigate the effects of cyclopentolate on ultrasonographic parameters of eye structures, intraocular pressure (IOP), tear production, and pupil size in normal donkeys. Sixteen eyes of eight clinically healthy adult donkeys (2-2.5 years old) weighing 295 ± 34 kg (mean ± standard deviation) were used in this study. Cyclopentolate hydrochloride 1% was instilled in a randomly selected eye and the other eye received normal saline drops as a control. The effect of cyclopentolate was evaluated by ultrasonography. Additionally, changes in IOP and tear production were ...
Pagliara E, Nicolo A, Rossi C, Cammaresi C, Donadio G, Bertuglia A.Perineural anaesthesia is an essential part of lameness investigation in horses. Painful reactions to injections imply a high risk of accidents for veterinarians. To evaluate the efficacy of two topical anaesthetic creams on desensitization of the skin at two perineural injection sites and to evaluate the effects these formulations may have on pain perception distally to the application sites. Randomized, blind, prospective study. 14 healthy horses were randomly divided in two groups of 7 horses each, one treated with EMLA and one with PLIAGLIS preparations. The mechanical nociceptive thresh...
Bessonnat A, Vanore M.Evaluate the effect of repeated doses of topical 1% cyclopentolate hydrochloride alone and in combination with topical 2.5% phenylephrine on pupil diameter (PD), tear production (STT-1), intraocular pressure (IOP), digestive function (gut motility and feces production), and heart rate (HR). Methods: Six healthy mares. Methods: In a prospective, randomized, controlled, and crossover design study, the left eye of six healthy mares was administered 0.2 mL of cyclopentolate alone and in combination with 0.2 mL of phenylephrine. The drugs were administered 3 times a day for 1 day, twice a day fo...
Rahman AZA, Adzahan NM, Zakaria Z, Mayaki AM.Horse wounds can be easily infected with bacteria depending on the nature of its cause such as laceration, abrasion, or puncture as well as the nature of its environment. Various treatments are available in managing open wounds, including the usage of topical antibiotics and antiseptics. However, antibiotic resistance has been a major concern attributed with chronic wound infection. The aim of this study was to test the efficacy of ionized water at different pH against the growth of common bacteria from horse wounds. Methods: Ten swab samples from equine infected wounds were collected and bact...
Ström L, Dalin F, Domberg M, Stenlund C, Bondesson U, Hedeland M, Toutain PL, Ekstrand C.Topical ophthalmic atropine sulfate is an important part of the treatment protocol in equine uveitis. Frequent administration of topical atropine may cause decreased intestinal motility and colic in horses due to systemic exposure. Atropine pharmacokinetics are unknown in horses and this knowledge gap could impede the use of atropine because of the presumed risk of unwanted effects. Additional information could therefore increase safety in atropine treatment. Results: Atropine sulfate (1 mg) was administered in two experiments: In part I, atropine sulfate was administered intravenously and t...
Atiba A, Ghazy A, Hamad MH.Cutaneous pythiosis in horses is a chronic ulcerative granulomatous disease caused by the oomycete Pythium insidiosum. Objective: The objective of the present study was to evaluate the response of cutaneous pythiosis in horses to surgical excision and topical dimethyl sulphoxide (DMSO). Methods: Thirty horses were presented clinically with pruritus, fistulae discharging serosanguineous fluid, and output kunkers in different body areas (limb, abdomen, neck, and face). The clinical diagnosis was confirmed by isolation of the causative agent and histopathology. All animals were treated by surgica...
Stucki M, Voegel CD, Binz TM, Kraemer T, Lavaud A, Voelter K.Equine sport agencies list steroids as prohibited substances for competing horses. Objective: The objective of this study was to investigate if the controlled substances dexamethasone and prednisolone are detectable in equine serum and urine samples during and after treatment with eye drops and if this can generate a positive doping test. Methods: Prospective cohort study. Methods: The study cohort included 11 horses. One eye of the horses was treated with either dexamethasone (Maxitrol 0.1%, n = 5 eyes) or prednisolone (Pred forte 1%, n = 6 eyes) eye drops 3 times daily for 14 days. Dexa...
Robinson MA, Stefanovski D, You Y, Boston RC, Soma LR.Capsaicinoids deter horses from chewing on bandages and are applied topically to provide analgesia to musculoskeletal injuries. They are banned during competition due to their nerve blocking properties. The pharmacokinetics of oral (PO) and direct gastric administration via nasogastric tube (NG), or topical (TOP) administration of two capsaicinoid-containing products were investigated, and the withdrawal times required prior to competition were estimated. Capsaicin (CAP) and dihydrocapsaicin (DCAP) were quantified in plasma, and both compounds were best described by a delayed absorption two co...
Lohse J, Pietrantoni P, Tummers C.Burn injuries are uncommon in large animals and there are no reports of these injuries in donkeys. Burns cause local and systemic effects. Extensive thermal injuries can be challenging to manage and the extent of the burn surface affected will directly impact the severity of the illness and the prognosis. Burns are classified according to the depth of injury into four categories, from first-degree burns, and the least affect to fourth-degree burns, which are the more severely affected patients. This case report describes the medical management of four donkeys that sustained various degrees of ...
Weber LA, Funtan A, Paschke R, Delarocque J, Kalbitz J, Meißner J, Feige K, Kietzmann M, Cavalleri JV.Equine sarcoid (ES) is the most prevalent skin tumor in equids worldwide. Additionally, aging grey horses frequently suffer from equine malignant melanoma (EMM). Current local therapies targeting these skin tumors remain challenging. Therefore, more feasible topical treatment options should be considered. In order to develop a topical therapy against ES and EMM, betulinyl-bis-sulfamate and NVX-207, derivatives of the naturally occurring betulin and betulinic acid, respectively, were evaluated for their antiproliferative (crystal violet staining assay), cytotoxic (MTS assay) and apoptotic (Anne...
Chen T, Ward DA.To determine tear volume, turnover rate, and flow rate in ophthalmologically normal horses by use of fluorophotometry. Methods: 12 mares free of ophthalmic disease. Methods: 2 microL of 10% sodium fluorescein was instilled onto 1 eye of each horse, and tear samples were collected via microcapillary tubes from the inferonasal conjunctival culde-sac at 0, 2, 4, 6, 10, 15, and 20 minutes after instillation. Collected tear samples were then measured for fluorescein concentrations with a computerized scanning ocular fluorophotometer. A decay curve plot of concentration changes over time was used to...
Tóth T, Broström H, Båverud V, Emanuelson U, Bagge E, Karlsson T, Bergvall K.Treatment and protection of wounds in horses can be challenging; protecting bandages may be difficult to apply on the proximal extremities and the body. Unprotected wounds carry an increased risk of bacterial contamination and subsequent infection which can lead to delayed wound healing. Topical treatment with antimicrobials is one possibility to prevent bacterial colonization or infection, but the frequent use of antimicrobials ultimately leads to development of bacterial resistance which is an increasing concern in both human and veterinary medicine. Methods: Standardized wounds were created...
Tsang AS, Dart AJ, Sole-Guitart A, Dart CM, Perkins NR, Jeffcott LB.To compare the effect of application of manuka honey with unique manuka factor (UMF) 5 or 20 with a generic multifloral honey on equine wound healing variables. Methods: Two full-thickness skin wounds (2.5 × 2.5 cm) were created on the metatarsus of both hindlimbs of eight Standardbred horses. The wounds on each horse were assigned to 1 of 4 treatments: UMF20 (UMF20) and UMF5 (UMF5) manuka honey; generic multifloral honey (GH); and a saline control. Bandages were changed daily for 12 days, after which treatment was stopped and the bandages were removed. Wound area was measured on day ...
Stahl J, Braun M, Siebert J, Kietzmann M.A water based combination of 0.1% octenidine dihydrochloride and 2% 2 - phenoxyethanol is registered in many European countries as an antiseptic solution (octenisept®) for topical treatment with high antimicrobial activity for human use, but octenidine based products have not been registered for veterinary use yet. The aim of the present study was to investigate whether octenidine dihydrochloride or 2 -phenoxyethanol, the two main components of this disinfectant, permeate through animal skin in vitro. Therefore, permeation studies were conducted using Franz-type diffusion cells. 2 ml of the t...
Wilmink JM, Ladefoged S, Jongbloets A, Vernooij JCM.The effect of dressings saturated with either a standardized suspension of probiotic bacteria or saline on healing of traumatic distal limb wounds in horses was evaluated for 24 days, and the systemic inflammatory effect was assessed. The wounds were divided in two groups based on the phase of healing: wounds with an incomplete (ICGB) or a complete granulation bed (CGB). The wound area was expressed as percentage of the wound area at day 0 and defined as relative wound area. The mean relative wound area decreased faster in probiotic than saline treated wounds. The difference was most obvious i...
Mirzaeei S, Faryadras FB, Mehrandish S, Rezaei L, Daneshgar F, Karami A.Prolonging the drug release can be a suitable approach to overcome the challenges related to topical ophthalmic administration of drugs especially the ones prescribed for chronic ailments. The sustained delivery of the drug would reduce the required frequency of administration which could extremely improve patient compliance and feeling of well-being. This study aimed to develop nanofibrous inserts for sustained ophthalmic delivery of timolol maleate (TIM) for the treatment of glaucoma. Unassigned: Polycaprolactone-based nanofibers containing TIM were prepared using pure polycaprolactone or a ...
Smith G, Bertone AL, Kaeding C, Simmons EJ, Apostoles S.To evaluate the effect of topically applied dimethylsulfoxide (DMSO) on lipopolysaccharide (LPS)-induced synovitis in the mid-carpal joint. Methods: 6 sound, healthy, adult horses (12 carpi). Methods: In a double-blinded, crossover, paired study with a 1-week washout period, mid-carpal joints were allocated to group 1 (DMSO, n = 6) or group 2 (control, n = 6). Each joint was injected with 1.3 ml (0.0125 ng/dl) of LPS to induce synovitis. For group-1 joints, DMSO gel (15 g; 90%) was applied after injection of LPS and at 12-hour intervals for 60 hours. Joints of group 2 received LPS, but not DMS...
Plummer CE, Polk T, Sharma J, Bae SS, Barr O, Jones A, Kitchen H, Wilhelmy M, Devin K, Clay Smith W, Kolaczkowski BD, Larkin J.Equine recurrent uveitis (ERU) is a painful and debilitating autoimmune disease and represents the only spontaneous model of human recurrent uveitis (RU). Despite the efficacy of existing treatments, RU remains a leading cause of visual handicap in horses and humans. Cytokines, which utilize Janus kinase 2 (Jak2) for signaling, drive the inflammatory processes in ERU that promote blindness. Notably, suppressor of cytokine signaling 1 (SOCS1), which naturally limits the activation of Jak2 through binding interactions, is often deficient in autoimmune disease patients. Significantly, we previous...
Southwood LL, Baxter GM.Recent advances in instrument sterilization include the introduction of gas plasma sterilization and the increased use of glutaraldehyde. Gas plasma sterilization has the advantages of no toxic residue effects, reduced turnover time, and applicability for sterilization of heat- and moisture-sensitive instruments. Chlorhexidine gluconate (4%) appears to be a superior preoperative surgical scrub for both the surgeon and the patient because of its increased antimicrobial efficacy, residual activity, and minimal tissue reactions. There are many new wound dressings and topical medications for treat...
McMullan WC, Joyce JR, Hanselka DV, Heitmann JM.Amphotericin B was used systemically or locally, or both, in the treatment of localized subcutaneous phycomycosis in horses. In 8 of 10 cases, the results were satisfactory. Intravenous treatment was well tolerated at an average starting daily dosage of 0.38 mg/kg, increasing up to as high as 1.47 mg/kg. It was concluded that the ideal treatment regimen would include early surgical removal of the lesion followed by daily intravenous and topical administration of amphotericin B, with periodic extirpation of small necrotic tracts as necessary.
Weber LA, Puff C, Kalbitz J, Kietzmann M, Feige K, Bosse K, Rohn K, Cavalleri JV.The naturally occurring betulinic acid (BA) and its derivative NVX-207 show anticancer effects against equine malignant melanoma (EMM) cells and a potent permeation in isolated equine skin in vitro. The aim of the study was to determine the in vivo concentration profiles of BA and NVX-207 in equine skin and assess the compounds' local and systemic tolerability with the intent of developing a topical therapy against EMM. Eight horses were treated percutaneously in a crossover design with 1% BA, 1% NVX-207 or a placebo in a respective vehicle twice a day for seven consecutive days with a seven-d...
de Raat IJ, van den Boom R, van Poppel M, van Oldruitenborgh-Oosterbaan MM.Insect bite hypersensitivity (IBH) in horses is most likely caused by Culicoides species, although other insects may also play a role. Until now no effective cure has been found for this condition, although numerous therapeutic and preventive measures have been used to control insect hypersensitivity. One such method is to apply a topical insecticide to horses. In this study, the effect of a topical insecticide containing permethrin (3.6%) was examined in seven pairs of horses. The horses were placed inside a tent trap to collect Culicoides spp. and other insects attracted to the horses on two...
Weber LA, Delarocque J, Feige K, Kietzmann M, Kalbitz J, Meißner J, Paschke R, Cavalleri JV.The naturally occurring betulinic acid (BA) and its derivative NVX-207 induce apoptosis in equine melanoma cells in vitro. After topical application, high concentrations of the substances can be reached in healthy equine skin. With the aim to investigate the effect and safety of topically applied BA and NVX-207 in horses with melanocytic tumors, the longitudinal, prospective, randomized, double-blind, placebo-controlled study protocol included eighteen Lipizzaner mares with early-stage cutaneous melanoma assigned to three groups. Melanocytic lesions were topically treated either with a placebo...
Richter M, Hauser B, Kaps S, Spiess BM.A 5-year-old Holsteiner gelding from Germany was presented 2 months after a whitish discoloration of the left cornea was observed. Cytologic examination revealed intra- and extracellular globular structures, up to 4 micro m in size, consisting of a central spherical deeply basophilic body surrounded by an unstained halo. The structures were morphologically consistent with Histoplasma spp. Infection with Histoplasma organisms is not endemic in Europe. Topical use of fluconazole was successful in eliminating Histoplasma organisms within 10 days of initiation of treatment.
Hendrix DV, Stuffle JL, Cox SK.To evaluate the pharmacokinetics of topically applied ciprofloxacin 0.3% ophthalmic solution in tears of healthy horses. Methods: Twenty healthy, adult, mixed-breed horses. Methods: Twenty study horses were confirmed free of ophthalmic disease by complete ophthalmic examination. Seventy microliters of 0.3% ciprofloxacin (Ciloxan) was placed in the ventral cul-de-sac of each eye using a microliter syringe and 19-g cannula. Population kinetics were carried out by sampling the tear film from the lower cul-de-sac of each eye with tear test strips at 5, 10, 15 and 30 min and 1, 2, 4 and 6 h post ad...
Gilger BC, Michau TM, Salmon JH.The purpose of this study is to describe clinical and histologic findings, treatment, and outcome of horses with suspected immune-mediated keratitis (IMMK). Methods: Retrospective study. Methods: Nineteen horses that presented to NCSU-VTH from 1998 to 2004 with IMMK. Procedures Information retrieved from the medical records included signalment, duration of clinical signs, therapy prior to initial examination, ophthalmic abnormalities, diagnostics performed, therapy instituted, and long-term vision. Results: Nineteen horses (22 eyes) were diagnosed with IMMK. Three distinct clinical groups were...
Harmon CCG, Hawkins JF, Li J, Connell S, Miller M, Saenger M, Freeman LJ.OBJECTIVE To determine the effects of 3 topically applied treatments (1% silver sulfadiazine cream [SSC], triple antimicrobial ointment [TAO], and hyperosmolar nanoemulsion [HNE]) on microbial counts, exuberant granulation tissue (EGT) development, and reepithelialization of contaminated wounds at the distal aspect of the limbs of horses. ANIMALS 8 healthy adult horses. PROCEDURES A 2.5 × 2.5-cm, full-thickness, cutaneous wound was created at the dorsal aspect of each metacarpus and metatarsus (1 wound/limb/horse), covered with nonadhesive dressing, and bandaged. Wounds were inoculated with b...
Marshall K, Marsella R.Increased antimicrobial resistance highlights the need for alternatives to antibiotics. Bacteriophages, which are benign viruses that kill bacteria, are promising. We studied the efficacy of topical bacteriophages for treating equine staphylococcal superficial pyodermas. Eight isolates were tested against a bacteriophage bank, and a cocktail consisting of two bacteriophages was prepared. Twenty horses with clinical and cytological evidence of superficial pyoderma and confirmed infection based on swabbed culture were enrolled in the study. Each horse received both the bacteriophage cocktail a...
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...
Weber LA, Funtan A, Paschke R, Delarocque J, Kalbitz J, Meißner J, Feige K, Kietzmann M, Cavalleri JV.Equine sarcoid (ES) is the most prevalent skin tumor in equids worldwide. Additionally, aging grey horses frequently suffer from equine malignant melanoma (EMM). Current local therapies targeting these skin tumors remain challenging. Therefore, more feasible topical treatment options should be considered. In order to develop a topical therapy against ES and EMM, betulinyl-bis-sulfamate and NVX-207, derivatives of the naturally occurring betulin and betulinic acid, respectively, were evaluated for their antiproliferative (crystal violet staining assay), cytotoxic (MTS assay) and apoptotic (Anne...
Stahl J, Kietzmann M.The effect of physical and chemical permeation enhancers on in vitro transdermal permeation of lidocaine was investigated in the horse.Therefore, the effect of six vehicles (phosphate-buffered saline (PBS), 50% ethanol, 50% propylene glycol, 50% isopropylalcohol, 50% isopropylalcohol/isopropylmyristate and 50% dimethylsulfoxide) was examined as well as the effect of microneedle pretreatment with different needle lengths on transdermal drug delivery of lidocaine.The skin was obtained from the thorax of six Warmblood horses and was stored up to two weeks at - 20°C. Franz-type diffusion cells we...
Hanson RR.Extensive thermal injuries in horses can be difficult to manage. The large surface of the burn dramatically increases the potential for loss of fluids,electrolytes, and calories. Burns are classified by the depth of injury: first-degree burns involve only the most superficial layers of the epidermis;second-degree burns involve the entire epidermis and can be superficial or deep; third-degree burns are characterized by loss of the epidermal and dermal components; and fourth-degree burns involve all the skin and underlying muscle, bone, and ligaments. Burns cause local and systemic effects. Rout...
Levine DG, Epstein KL, Neelis DA, Ross MW.To determine whether topical application of 1% diclofenac sodium cream would decrease inflammation at sites of IV regional limb perfusion (IVRLP) in healthy horses. Methods: 6 healthy adult horses (12 forelimbs). Methods: Bilateral IVRLP with 2.5 g of amikacin sulfate was performed twice in each horse, with 24 hours between each session. Horses were treated with topical 1% diclofenac liposomal cream (treated limbs) or a placebo cream (control limbs). All injection sites were evaluated before the first IVRLP session and 24 hours after the second session by means of ultrasonographic examination ...
Haspeslagh M, Jordana Garcia M, Vlaminck LEM, Martens AM.Previous studies mention the use of topical acyclovir for the treatment of equine sarcoids. Success rates vary and since the bovine papillomavirus (BPV) lacks the presence of a kinase necessary to activate acyclovir, there is no proof of its activity against equine sarcoids. Results: Twenty-four equine sarcoids were topically treated with acyclovir cream and 25 with a placebo. Both creams were applied twice daily during 6 months. Before the start of the treatment and further on a monthly basis, photographs and swabs were obtained. On the photographs, sarcoid diameter and surface area were meas...
Munday JS, Hardcastle MR, Sim M.A 10-year-old horse presented with two 3-cm diameter exophytic masses over the fetlock. Histology was consistent with a hyperplastic squamous papilloma and numerous cell changes consistent with papillomavirus (PV) infection were visible. Partial sequences of PV L1 and E1 ORFs were amplified using consensus PCR primers. The sequences were most similar to Equus caballus type 1 (EcPV1). However, as the sequences were only around 73% similar to EcPV1, they appear to be from a novel PV type that is likely to be within the genus. The papillomas were treated with topical imiquimod and resolved withi...
Vissani MA, Perglione CO, Zabal O, Alvarez G, Thiry E, Barrandeguy M, Parreño V.Equid alphaherpesvirus 3 (EHV-3) is the etiological agent of equine coital exanthema (ECE). Because no vaccines or antiviral therapies are available, prevention consists of clinical examination of mares and stallions before mating or semen collection and resting from breeding activities when lesions are present. However, this methodology does not identify subclinically infected animals. Ganciclovir is the most potent compound known to reduce EHV-3 replication. This study aimed to evaluate the efficacy of topical ganciclovir application to reduce EHV-3 replication in experimentally infected mar...
Mills PC, Cross SE.Little is known about the transdermal penetration of hydrocortisone in the horse and, although commercial formulations containing hydrocortisone are registered for topical use in the horse, there have been no studies investigating the movement of this glucocorticoid through different regions of equine skin. Skin was harvested from the thorax, groin and leg (dorsal metacarpal) regions of five Thoroughbred geldings and frozen (-20 degrees C) until required. Defrosted skin was placed in Franz-type diffusion cells and the amount of radiolabelled ((3)H) hydrocortisone, in a saturated solution of un...
Williams LB, Pinard CL.Corneal ulceration is commonly diagnosed by equine veterinarians. A complete ophthalmic examination as well as fluorescein staining, corneal cytology, and corneal bacterial (aerobic) and fungal culture and sensitivity testing are necessary for all infected corneal ulcers. Appropriate topical antibiotics, topical atropine, and systemic NSAIDs are indicated for all corneal ulcers. If keratomalacia (melting) is observed, anticollagenase/antiprotease therapy, such as autologous serum, is indicated. If fungal infection is suspected, antifungal therapy is a necessity. Subpalpebral lavage systems all...
Pettersson CM, Broström H, Humblot P, Bergvall KE.Equine sarcoids are the most prevalent skin neoplasm in horses worldwide. Although several treatments are available, none are consistently effective and recurrence is common. Objective: To evaluate the efficacy and safety of topical imiquimod 5% cream and Sanguinaria canadensis + zinc chloride for treatment of equine sarcoids and investigate possible systemic effects on distant untreated sarcoids. Unassigned: Twenty-five client-owned horses with a total of 164 tumours were included in the study. Fifty-seven tumours were treated and 107 tumours were left untreated. Methods: Skin biopsy sample...