Mortierella wolfii keratomycosis in a horse

Purpose To describe a case of superficial keratomycosis caused by Mortierella wolfii (M. wolfii) in a horse. Methods A thoroughbred filly was presented with painful right eye of 2 days’ duration. A superficial corneal ulcer was observed ventrally together with multifocal punctuate opacities axially. Samples were collected by swabbing and scraping the ulcerated lesion and submitted for microbiologic and cytologic examination. Results Microscopic evaluation of debrided corneal tissue revealed the presence of nonseptate fungal hyphae, and culture of a corneal swab yielded fungal growth. Medical treatment with topical antifungal, antibiotic and autogenous serum and systemic anti‐inflammatory resolved the problem within 2 weeks. Conclusions Cytologic evaluation of a corneal scraping was useful to make a clinical diagnosis of keratomycosis. Based on the mycological characteristics, the fungus isolated from the corneal lesion was identified as M. wolfii. To the authors’ knowledge, this is the first case report of equine keratomycosis associated with this fungus, although the organism is known to infect various organs of cattle.     

Ulcerative fungal keratitis in a Brown Swiss cow

An 11‐year‐old Brown Swiss cow was referred to the Farm Animal Department of the Veterinary Teaching Hospital in Zurich, Switzerland, because of lateral recumbency due to puerperal hemolytic anemia. The animal had developed enophthalmos due to dehydration at the time of presentation. Two days after hospitalization, the cow showed blepharospasm and epiphora of the right eye. Ophthalmic examination of the right eye revealed a fluorescein‐positive, paraxial, superficial corneal ulcer with focal edema, and mild superficial neovascularization. White corneal stromal infiltrates were seen at the edges of the ulcer bed. After initial topical treatment with an antibiotic ointment (Neomycin 3.5 mg/g, Bacitracin 250 IU/g) three times a day, an increase in corneal infiltrates was noted on re‐examination 2 days later. Several fluorescein‐negative, punctate, stromal, white opacities were seen dorsal to the ulcer. Cytology demonstrated the presence of fungal hyphae. Topical treatment with 2% miconazole ointment and 0.36% K‐EDTA eye drops six times daily and four times daily, respectively, from the second day and continued antibiotics three times daily resolved the clinical symptoms within 6 days. Fungal culture identified the fungal organism as Eurotium amstelodami.     

Corneal plaque containing levofloxacin in a dog

A 13‐year‐old castrated male Yorkshire terrier developed a corneal ulcer 2 weeks after intracapsular lens extraction (ICLE) in the right eye. The corneal ulcer was treated with levofloxacin eye drops. A plaque with a white luster developed in the central cornea 2 weeks after treatment with levofloxacin eye drops. The corneal plaque was surgically removed under inhalant anesthesia. The corneal plaque displayed antimicrobial activity against Escherichia coli. Furthermore, levofloxacin content in the plaque was confirmed by matrix‐assisted laser desorption/ionization time‐of‐flight/time‐of‐flight (MALDI‐TOF/TOF) mass spectrometry (MS). The corneal ulcer completely resolved 2 weeks after the surgical removal of the corneal lesion and replacement of levofloxacin eye drops with tobramycin eye drops. Although the topical use of levofloxacin is unlikely to lead to corneal chemical deposits due to the high water solubility of the drug compared to other topical fluoroquinolones, this patient developed corneal plaque of the antibiotic drop.     

Osseous metaplasia in the conjunctiva of a horse presenting with recurrent ulcerative keratitis

A 13‐year‐old Thoroughbred gelding presented with a 6 month history of recurrent conjunctivitis, dacryocystitis and corneal ulceration affecting the left eye (OS). Treatment had included multiple topical antibiotic and anti‐inflammatory preparations, nasolacrimal system flushing and an injection of methylprednisolone acetate (MPA) (Depomedrone) ¹ administered subconjunctivally into the left lower eyelid. No mechanical cause for the ulcerative keratitis could be visualised but digital palpation revealed a firm linear structure in the central palpebral conjunctiva of the lower eyelid. An excisional biopsy was performed and histopathological examination revealed the lesion to be a region of osseous metaplasia. Following excision of the lesion, the corneal ulcer resolved and the eye remained disease free over a 4 year follow‐up period. A causal link between the osseous metaplasia and the recurrent ulcerative keratitis was therefore suspected. This report describes the management of this case and discusses the pathogenesis of osseous metaplasia and the use of subconjunctival corticosteroids.     

Response of feline eosinophilic plaques and lip ulcers to amoxicillin trihydrate-clavulanate potassium therapy: a randomized, double-blind placebo-controlled prospective study

In this study, we evaluated the treatment of feline eosinophilic plaques and lip ulcers with amoxicillin trihydrate–potassium clavulanate (Clavamox^®; Pfizer Animal Health). Nineteen cats with clinical and cytological findings consistent with eosinophilic plaques and/or lip ulcers were enrolled. Lesions were photographed and their areas measured in square centimetres before and after 21 days of therapy with either flavoured amoxicillin‐clavulanate suspension or flavoured placebo suspension. Sixteen cats completed the study, with nine plaque lesions (four treatment and five placebo) and eight lip ulcer lesions (four treatment and four placebo) included in the analysis. All lesions were shown to have infection, with bacterial phagocytosis present on cytological examination. Coagulase‐positive staphylococci were the most commonly isolated bacteria. The amoxicillin‐clavulanate‐treated eosinophilic plaque group had a statistically significant 96.2% reduction in mean lesion size (?7.60 cm², P = 0.0078) and an 80% reduction in mean percentage of microscopic fields demonstrating evidence of bacterial infection (P < 0.0001), whereas the placebo group did not. The amoxicillin‐clavulanate‐treated lip ulcer group had a 42.6% decrease in mean lesion size (?0.25 cm², P = 0.4125) and the placebo group a 36.6% increase (+0.49 cm², P = 0.1575), although neither change was statistically significant. The amoxicillin‐clavulanate‐treated lip ulcer group had a statistically significant 65.0% reduction in mean percentage of microscopic fields demonstrating evidence of bacterial infection (P < 0.0001), while no significant reduction was observed in the placebo group. A suspension of amoxicillin trihydrate–potassium clavulanate is an effective monotherapy for the treatment of feline eosinophilic plaques.     

Tolerance of the rabbit cornea to an n-butyl-ester cyanoacrylate adhesive (Vetbond)

Objective An n‐butyl‐ester cyanoacrylate adhesive available for veterinary surgery (Vetbond^®, 3M) was tested in rabbits for corneal irritation. Procedures Two experimental procedures were used on 24 rabbits: injection of the adhesive into an intralamellar corneal pocket (n = 10) and application of the glue to a mid‐stromal corneal defect (n = 14). In both experiments the eyes were examined for 20 days for evidence of corneal irritation and tolerance. At the end of each experiment, histopathologic studies were performed on all corneas. Results The corneal reaction to the intrastromally injected cyanoacrylate was characterized clinically by slight edema and vascularization localized to the vicinity of the adhesive. A moderate foreign body‐type reaction was found histologically. Following application of the adhesive to a central stromal defect, the treated corneas remained totally clear and histopathologic examination showed that the healing process was not altered compared to the controls. The mean retention time of the glue patch was 14 days. Conclusions Intrastromal injection and surface application to a corneal defect of n‐butyl‐ester cyanoacrylate to a corneal defect induced only a mild inflammatory response and did not interfere with the reparative process. These findings suggest that this surgical adhesive would be acceptable for treating corneal ulcerations in animals.     

A novel herpesvirus associated with chronic superficial keratitis and proliferative conjunctivitis in a great horned owl (Bubo virginianus)

An adult great‐horned owl (Bubo virginianus; GHOW) presented with a history of recurrent corneal ulceration of the right eye (OD). Findings included ulcerative superficial keratitis, proliferative conjunctivitis, and iris pigmentary changes. The ulcer was initially nonresponsive to medical therapy, but showed rapid and appropriate healing following diamond burr debridement. Proliferative conjunctivitis markedly improved following topical antiviral therapy with cidofovir 1%, interferon alpha 2B ophthalmic solutions, and oral l ‐lysine. Histopathologic evaluation of a conjunctival biopsy revealed epithelial features suspicious for viral cytopathic changes and intranuclear structures suspicious for viral inclusions, suggestive of a possible viral‐induced papillomatous conjunctivitis. A novel alphaherpesvirus, referred to as Strigid Herpesvirus 1 (StrHV1), was identified using PCR and gene sequencing. This case represents a new clinical manifestation of a previously unreported herpesvirus in the GHOW. Identification of the herpes virus was critical to administration of appropriate therapy and resolution of the conjunctivitis, and corneal epithelial debridement promoted resolution of the chronic corneal epithelial defect.     

Intracranial migration of Eucoleus (Capillaria) boehmi in a dog

A 4‐year‐old, spayed‐female great Dane was referred for surgical treatment of a suspected meningioma, diagnosed on magnetic resonance imaging 10 days prior to presentation. The suspected meningioma was removed via image‐guided stereotactic craniotomy. Histopathological diagnosis was severe, locally extensive, chronic meningoencephalitis with an intralesional nematode egg. The egg was morphologically consistent with Eucoleus boehmi, and aberrant migration into the cranial cavity was the presumed cause of this lesion. Three faecal samples were collected and revealed 4+ E. boehmi eggs. Treatment involved 110 mg/kg fenbendazole (Panacur, Intervet) orally twice daily for 14 days. Nematodes including E. boehmi are a previously un‐recognised source of intracranial disease in dogs, and should be considered as a differential for mass‐like lesions visualised by magnetic resonance imaging.     

Entropion,Corneal Ulcer and Corneal Haemorrhages in a One‐Humped Camel (Camelus dromedarius)

An unusual case of entropion, corneal ulcer and corneal haemorrhages in a one‐humped camel (Camelus dromedaries) is described. The most prominent clinical findings were entropion of both eyelids, severe blephrospasm, epiphora, conjunctivitis, conjunctival oedema, mucopurulent conjunctival discharges, hyperaemia, lacrimation and photophobia. Corneal ulcers and corneal haemorrhages were also observed.     

FOCAL SKELETAL MUSCLE UPTAKE OF 99mTECHNETIUM‐HYDROXYMETHYLENE Diphosphonate FOLLOWING PERONEAL NERVE BLOCKS IN HORSES

We have observed focal skeletal muscle uptake of ^99mTechnetium‐hydroxymethylene diphosphonate (Tc‐HDP), which could mimic a tibial lesion, in horses following peroneal nerve blocks. To characterize this observation further, 45 bone phase scintigrams were performed in 12 horses undergoing peroneal nerve blocks. Scans were performed before, and 1, 3, 7, and 14 days postblock. The superficial and deep branches of the peroneal nerve were blocked by injecting 10 ml of 2% mepivacaine in one limb and 20 ml in the other. Images were evaluated for uptake at the block site and uptake likely to mimic a tibial lesion. Regions of interest were placed over the block site and distal tibia. Count density ratios were used to estimate change in uptake intensity over time. The overall proportion affected was 0.52 (95% confidence interval [CI], 0.36–0.68; P<0.001) 1 day postblock and 0.24 (95% CI, 0.13–0.40; P=0.005) 3 days postblock. The overall proportion likely to mimic a tibial lesion was 0.19 (95% CI, 0.09–0.33; P<0.001) 1 day postblock and 0.21 (95% CI, 0.09–0.40; P=0.005) 3 days postblock. Focal skeletal muscle uptake was seen in only one horse 7 days postblock. Increased uptake intensity was associated with higher local anesthetic dose (P=0.042). Peroneal nerve blocks cause focal skeletal muscle uptake of ^99mTc‐HDP on bone phase scintigraphy. This occurs in approximately 50% of blocked limbs and can mimic a tibial lesion on the lateral view in approximately 20% of blocked limbs.     

Mitomycin C: a promising agent for the treatment of canine corneal scarring

Objective To evaluate the safety and efficacy of mitomycin C (MMC) in prevention of canine corneal scarring. Methods With an in vitro approach using healthy canine corneas, cultures of primary canine corneal fibroblasts or myofibroblasts were generated. Primary canine corneal fibroblasts were obtained by growing corneal buttons in minimal essential medium supplemented with 10% fetal bovine serum. Canine corneal myofibroblasts were produced by growing cultures in serum‐free medium containing transforming growth factor β1 (1 ng/mL). Trypan blue assay and phase‐contrast microscopy were used to evaluate the toxicity of three doses of MMC (0.002%, 0.02% and 0.04%). Real‐time PCR, immunoblot, and immunocytochemistry techniques were used to determine MMC efficacy to inhibit markers of canine corneal scarring. Results A single 2‐min treatment of 0.02% or less MMC did not alter canine corneal fibroblast or keratocyte phenotype, viability, or growth. The 0.02% dose substantially reduced myofibroblast formation (up to 67%; P < 0.001), as measured by the change in RNA and protein expression of fibrosis biomarkers (α‐smooth muscle actin and F‐actin). Conclusion This in vitro study suggests that a single 2‐min 0.02% MMC treatment to the canine corneal keratocytes is safe and may be useful in decreasing canine corneal fibrous metaplasia. In vivo studies are warranted.     

Efficacy and safety of mitomycin C as an agent to treat corneal scarring in horses using an in vitro model

Objective Mitomycin C (MMC) is used clinically to treat corneal scarring in human patients. We investigated the safety and efficacy of MMC to treat corneal scarring in horses by examining its effects at the early and late stages of disease using an in vitro model. Procedure An in vitro model of equine corneal fibroblast (ECF) developed was used. The ECF or myofibroblast cultures were produced by growing primary ECF in the presence or absence of transforming growth factor beta‐1 (TGFβ1) under serum‐free conditions. The MMC dose for the equine cornea was defined with dose‐dependent trypan blue exclusion and (3‐4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assays after applying MMC to the cultures once for 2 min. The efficacy of MMC to control corneal scarring in horses was determined by measuring mRNA and protein expression of corneal scarring markers (alpha‐smooth muscle actin and F‐actin) with western blotting, immunocytochemistry and/or quantitative real‐time polymerase chain reactions. Results A single 2‐min treatment of 0.02% or less MMC did not alter ECF phenotype, viability, or cellular proliferation whereas 0.05% or higher MMC doses showed mild‐to‐moderate cellular toxicity. The TGFβ1 at 1 ng/mL showed significant myofibroblast formation in ECF under serum‐free conditions. A single 2‐min, 0.02% MMC treatment 24 h (early) after TGFβ1 stimulation significantly reduced conversion of ECF to myofibroblasts, however, a single 0.02% MMC treatment 11 days after TGFβ1 stimulation showed moderate myofibroblast inhibition. Conclusions That MMC safely and effectively reduced scarring in ECF by reducing the degree of transdifferentiation of corneal fibroblasts to myofibroblasts in vitro. Further clinical in vivo investigations are warranted using MMC in horses.     

Ulcerative keratitis in thoroughbred racehorses in Japan from 1997 to 2008

Objective To describe the number of cases, etiologies, healing times, and results of microbial culture and susceptibility testing of corneal ulcers in thoroughbred racehorses in Japan. Procedure Retrospective study of the medical records of racehorses belonging to the Japan Racing Association (JRA) from 1997 to 2008. Results A total of 2846 horses suffered ulcerative keratitis. These horses accounted for 90.5% of all the corneal problems and 54.9% of the entire number of horses with ocular diseases. Running in races was the cause in 64.3% of the cases. The mean healing time of the ulcers developed in races was 5.5 ± 9.6 days, which was shorter than that of the ulcers unrelated to racing (8.6 ± 11.7 days). In horses presented for examination by the next day after the race, healing was even more rapid (4.1 ± 7.5 days) than in horses presented later (12.4 ± 14.7 days). Microbial culture was performed on 74 samples of 58 horses. Forty‐four bacterial and four fungal organisms were isolated from 35 samples of 29 horses. Pseudomonas aeruginosa (10) and Streptococcus equi subspecies zooepidemicus (5) were the bacteria most frequently isolated. There was no tendency of increasing antibiotic resistance of these organisms. Conclusions Ulcerative keratitis is the most frequent corneal and ocular disease of the racehorse in Japan. Careful observation of the eyes after racing is necessary as early diagnosis and treatment of corneal ulcers speeds healing. Many antibiotic have efficacy against the bacterial isolates, however, potent antibiotics should be reserved for the most severe corneal ulcers.     

Ocular parameters in a captive colony of fruit bats

Objectives To establish normal reference ranges of ocular parameters including phenol read thread, palpebral fissure length, horizontal and vertical corneal diameter, upright and hanging intraocular pressure (IOP) and to report ophthalmic examination findings of the anterior segment and lens, in a population of captive fruit bats. Animals studied Eyes of 30 bats of three species were included in this study: 10 (5 males, 5 females) Malayan Flying Foxes (Pteropus vampyrus), 10 (5 males, 5 females) Little Golden‐mantled Flying Foxes (Pteropus pumilus), and 10 (4 males, 6 females) Island Flying Foxes (Pteropus hypomelanus). Results The most common ophthalmic examination findings included iris‐iris persistent pupillary membranes (83%), nuclear sclerosis (56.7%), prominent arterial circle (40%), iridal hyperpigmented foci (30%), pupillary margin cysts (27%), and third eyelid defects (20%). The mean, among all species for: phenol red thread was 20.23 ± 1.28 mm/15 s both eyes (OU); palpebral fissure length was 13.34 ± 0.33 mm for OU; for horizontal corneal diameter was 10.72 ± 0.32 mm for OU; for vertical corneal diameter was 9.90 ± 0.30 mm for OU; for the hanging intraocular pressures was 19.38 ± 0.77 mmHg for OU; for upright IOP was 13.95 ± 0.60 mmHg for OU. Measurements for the individual species groups and eyes were also calculated. Conclusions Results revealed the IOP of bats in a hanging position were significantly higher than the IOP of bats in an upright position. The size of the bat, between the species, affected palpebral fissure length, horizontal corneal diameter, and vertical corneal diameter. Information about the ocular structures and normal ophthalmic parameters for the Pteropus species is crucial for species protection because of dependence on vision for survival.     

Otitis media‐interna and secondary meningitis associated with Corynebacterium pseudotuberculosis infection in a horse

A one‐year‐old Thoroughbred colt was evaluated because of facial nerve paralysis, ataxia and fever. Neurological evaluation found the colt to be obtunded and grade 3/5 ataxic in all 4 limbs. Right‐sided facial nerve paralysis was present and a large, deep corneal ulcer noted in the right eye. Signs of vestibular disease were also present, including circling towards the right and horizontal nystagmus. A complete blood count showed mild leucocytosis, neutrophilia and hyperfibrinogenaemia. A computed tomography (CT) examination of the skull was performed under general anaesthesia and a diagnosis of right sided otitis media‐interna was made. Culture of fluid taken from the middle ear and cerebrospinal fluid collected from the atlanto‐occipital site yielded pure growth of Corynebacterium pseudotuberculosis. Initial therapy consisted of antimicrobial treatment with cefotaxime and anti‐inflammatory treatment with flunixin meglumine. Six days after initiating treatment, the colt developed Clostridium difficile associated colitis. The colitis resolved with supportive care and the colt was discharged from the hospital receiving chloramphenicol. Eight months later, the colt continued to be mildly ataxic (grade 1/5), with a slight head tilt and facial nerve paralysis. To the authors' knowledge, this is the first reported case of otitis media‐interna due to C. pseudotuberculosis in the horse.     

Canine corneal fibroblast and myofibroblast transduction with AAV5

Objective The aims of this study were (1) to determine the efficacy of adeno‐associated vector serotype 5 (AAV5) for delivering gene therapy to canine corneal fibroblasts (CCFs) and myofibroblasts (CCMs) using enhanced green fluorescent protein (GFP) marker gene and (2) to evaluate the cytotoxicity of AAV5 to CCFs and CCMs using an in vitro model. Methods Healthy donor canine corneas were used to generate primary CCFs by growing cultures in minimal essential medium supplemented with 10% fetal bovine serum. Canine corneal myofibroblasts were produced by growing cultures in serum‐free medium containing transforming growth factor β1 (1 ng/mL). An AAV5 titer (6.5 × 10¹² μg/mL) expressing GFP under control of hybrid cytomegalovirus + chicken β‐actin promoters (AAV5‐gfp) was used to transduce CCF and CCM cultures. Delivered gene expression in CCFs and CCMs was quantified using immunocytochemistry, fluorescent microscopy, and real‐time PCR. Transduction efficacy of the AAV5 vector was determined by counting DAPI‐stained nuclei and EGFP‐positive cells in culture. Phase‐contrast microscopy, trypan blue, and dUTP nick end labeling (TUNEL) assays were used to determine the toxicity and safety of AAV5 in this canine corneal model. Results Topical AAV5 application successfully transduced a significant population of CCFs (42.8%; P < 0.01) and CCMs (28%; P < 0.01). Tested AAV5 did not affect CCF or CCM phenotype or cellular viability and did not cause significant cell death. Conclusions The tested AAV5 is an effective and safe vector for canine corneal gene therapy in this in vitro model. In vivo studies are warranted.     

Successful treatment of an unusually large corneal epithelial inclusion cyst using equine amniotic membrane in a dog

A 10‐year‐old intact male Yorkshire Terrier was referred for investigation of a large raised and nonpainful corneal lesion oculus dexter. Clinical examination revealed a pale, translucent corneal mass, which occupied half of the corneal surface and measured 11 mm × 11 mm × 13 mm. The mass was removed by superficial keratectomy and equine amniotic membrane (AM) was transplanted into the large corneal defect to cover the wound and provide tectonic support for the remaining cornea. The mass was histologically confirmed as a corneal epithelial inclusion cyst. There was no evidence of recurrence or complication at the surgical site 100 days postoperatively. Corneal epithelial inclusion cysts are uncommon in dogs. Although superficial keratectomy is the recommended treatment for corneal inclusion cyst, the combination of superficial keratectomy and AM transplantation had to be considered as an alternative for repair of large corneal defects. This is the first case report of the combined application of AM and superficial keratectomy to successfully treat a corneal inclusion cyst in a dog.     

Treatment of corneal ulceration and bullous keratopathy using a nictitating membrane flap in two horses

Objective

The aim of this study was to describe placement of a nictitating membrane flap as a treatment for corneal ulceration and bullous keratopathy in two horses.

Animals Studied

A 13-year-old American Saddlebred mare presented for severe corneal edema, superficial stromal ulceration, and a central bulla of the left eye. A 4-year-old Trakhener stallion also presented with a large axial bulla of the left eye with concurrent severe corneal edema and a deep stromal ulcer.

Procedure

A complete ophthalmic examination was performed. Samples were obtained for corneal cytology, and both horses were started on aggressive medical therapy. Both underwent general anesthesia for placement of a nictitating membrane flap and a subpalpebral lavage system (SPLS).

Results

Corneal cytology for each horse revealed a mixed bacterial population. Moderate Pseudomonas aeruginosa was cultured from the mare, while Aspergillus species and a few Enterococcus gallinarum were cultured from the stallion. The bullae in both horses resolved at 3 and 4 weeks and vision returned in the affected eye 4.5 and 3 months postoperatively at the last follow-up, respectively.

Conclusion

Aggressive medical management with concurrent placement of a nictitating membrane flap is effective to treat bullous keratopathy in two horses. The described treatments could be used to treat horses that develop severe or progressive bullous corneal lesions.     

Comparison of once-daily versus twice-weekly terbinafine administration for the treatment of canine Malassezia dermatitis - a pilot study

Background – Terbinafine, an allylamine antifungal, is used in pulsatile dose regimens for superficial mycoses in human medicine. Objectives – To compare the clinical efficacy of twice‐weekly versus once‐daily terbinafine administration to determine whether preliminary proof‐of‐concept evidence exists for pulsatile administration of terbinafine in the treatment of canine Malassezia dermatitis and to determine whether twice‐weekly treatment results in fewer clinical and owner‐perceived adverse events. Animals – Twenty client‐owned dogs with Malassezia dermatitis. Methods – In this randomized, single‐blinded clinical trial, dogs were randomly assigned to receive terbinafine (30 mg/kg) either once daily for 21 days (n = 10) or once daily on two consecutive days per week for six doses (n = 10). On day 0 and day 21, a mean yeast count was calculated from eight anatomical locations via adhesive tape‐strip cytology, clinical lesion scores were assigned to the same locations, and owners assessed pruritus using a visual analog scale. Results – There was no significant difference between treatment groups with respect to the reduction in mean yeast count (P = 0.343) and clinical lesion scores (P = 0.887). Pruritus measured by visual analog scale was significantly decreased in the twice‐weekly treatment group compared with the daily treatment group (P = 0.047). Seven of 20 dogs had a clinically measurable or owner‐reported adverse event during treatment that included gastrointestinal disturbances, excessive panting and elevated hepatic enzymes, with no significant difference noted between treatment groups. Conclusions and clinical importance – This pilot study indicates that twice‐weekly terbinafine administration may be an effective alternative treatment for canine Malassezia dermatitis and merits further investigation.