Epidemiology and clinical significance of canine distichiasis: A retrospective study of 291 cases.

OBJECTIVE: To describe the epidemiological factors and clinical significance of canine distichiasis. ANIMALS STUDIED: Two hundred and ninety-one client-owned dogs. METHODS: Retrospective study of medical records for canine patients diagnosed with distichiasis between 2010 and 2019 in an ophthalmology specialty practice. The breed, sex, skull conformation, coat type, age at the time of diagnosis, reason for presentation, clinical examination findings, and affected eyelid(s) were reviewed. RESULTS: The prevalence of distichiasis was 5.5% (95% confidence interval (CI): 4.9-6.1) in the population of dogs presented to an ophthalmology specialty practice. The breeds with the highest prevalence were English bulldogs (35.2%, 95% CI: 26.7-43.7) and American cocker spaniels (19.4%, 95% CI: 8.3-30.5). The prevalence was significantly higher in brachycephalic dogs (11.9%, 95% CI: 9.8-14.0) than in non-brachycephalic dogs (4.6%, 95% CI: 4.0-5.3) and in short-haired dogs (8.2%, 95% CI: 6.8-9.6) than in dogs with other coat types (5.3%, 95% CI: 4.5-6.1). Most dogs were affected bilaterally (63.6%, 95% CI: 58.0-69.1). Among dogs with clinical signs, 39.0% (95% CI: 26.5-51.4) exhibited corneal ulceration, including superficial ulcers (28.8%, 95% CI: 17.3-40.4) and deep stromal ulcers (10.2%, 95% CI: 2.5-17.8). Distichiasis was non-irritating in 85.0% (95% CI: 80.6-89.4) of affected dogs. CONCLUSION: This study reports the largest cohort of canine distichiasis to date. In a large proportion of dogs, distichiasis was a non-irritating condition. However, brachycephalic breeds, especially English bulldogs, were the most frequently and severely affected.

Outcome of medical therapy for keratomalacia in dogs.

OBJECTIVES: To evaluate the clinical and visual outcomes following intensive medical therapy for keratomalacia in dogs. MATERIALS AND METHODS: Medical records were screened to identify dogs with corneal ulcers and keratomalacia. All patients were given the same topical treatment protocol with frequent administrations of tobramycin in combination with equine serum. Surgical treatment during the first 15 days of follow-up was considered as medical treatment failure. RESULTS: We report on 57 ulcers with keratomalacia from 53 dogs. Medical treatment was successful in 31 of 57 ulcers with a median healing time of 5 days (range 2 to 15 days). At 60 days after epithelialisation, 14/15 medically-treated eyes were visual. In one case, corneal perforation was observed 1 month after healing and required surgical stabilisation. CLINICAL SIGNIFICANCE: Intensive medical therapy has the potential to achieve healing of some ulcers with keratomalacia. Surgical stabilisation in response to progression of stromal loss was required in less than half of the cases.

Conjunctival bacterial and fungal flora and cutaneous fungal flora in healthy domestic rabbits (Oryctolagus cuniculus).

OBJECTIVES: To determine the normal conjunctival bacterial and fungal flora in healthy rabbits, to compare the fungal flora from the conjunctival sac with periocular cutaneous fungal flora and to evaluate potential changes in type of micro-organisms over time. MATERIALS AND METHODS: Samples from 50 pet rabbits with a normal ophthalmic examination were obtained from conjunctival sacs using sterile cotton swabs and from the interpupillary skin space using a piece of sterile carpet. Samples were collected twice, 4 weeks apart, and cultured to evaluate bacterial and fungal populations. RESULTS: Bacteria were recovered from 35.9% of conjunctival swabs. Corynebacterium species (32.4%), Staphylococcus species (18.3%), Pasteurella species (9.9%) and Moraxella species (8.5%) were the most frequently isolated organisms. Fungi were recovered from 14.6% of conjunctival swabs. The most common fungal genera were Aspergillus (37%), Scopulariopsis (14.8%) and Penicillium (11.1%). Fungal cultures from periocular integument yielded positive results in 96.3% of samples; the same fungal organism was isolated in both conjunctival and cutaneous culture in nine of 20 rabbits (45%). When comparing results 4 weeks apart in 32 of 50 animals, only three rabbits with a positive bacterial culture and one rabbit with a positive fungal culture had the same result at the subsequent test. CLINICAL SIGNIFICANCE: Fungi and bacteria isolated from the conjunctival sac of rabbits may represent transient seeding from the environment. To our knowledge, this is the first report of fungal composition of the conjunctival sac of rabbits and evaluation of the potential transient nature of both bacterial and fungal composition of this conjunctival flora.