CLINICAL AND HISTOPATHOLOGIC OCULAR FINDINGS IN AQUARIUM-HOUSED COWNOSE RAYS (RHINOPTERA BONASUS).

Cownose rays (Rhinoptera bonasus) are susceptible to ocular disease with their prominent globes, but despite being popular animals housed in aquaria, there is little published information about their normal ocular anatomy and common pathologic ocular findings. A total of 63 live cownose rays (CNR) from three unrelated, separately housed groups had ocular examinations, and 5 adult rays were selected for ocular ultrasound. All examinations were performed out of the water, and most without anesthesia. Clinical findings were described, categorized, and scored by severity. Sixty-two of 63 rays (123 eyes) had clinical abnormalities, including 110 eyes with corneal pathology (mild = 76, moderate/severe = 34) and 74 eyes with intraocular pathology (mild = 44, moderate/severe = 30). Grey-to-white corneal opacities were the most common pathology (n = 58 rays/100 eyes) followed by cataracts (n = 41 rays/58 eyes), then persistent (or dysplastic) pupillary membranes (n = 14 rays/15 eyes). Most pathologic findings appeared inactive, but one aquarium had several CNR with active ocular pathology. There was a significant association between the diagnosis of moderate/severe corneal and intraocular pathology with age (P = 0.008 and P = 0.014, respectively) and weight (P = 0.001 and P = 0.039, respectively), as well as moderate/severe corneal pathology and group sampled (P = 0.03). There were no other significant variables identified. Additionally, histopathology of 14 eyes (11 rays) from two different facilities were examined, with keratitis (n = 8) and uveitis (n = 2) as the most common lesions. This study shows a high prevalence of pathologic ocular findings in cownose ray eyes with heavier adults more likely to be affected than lighter juveniles. Comprehensive ocular evaluation is important in this species and serial ocular exams and future studies should be pursued to monitor ocular disease progression and better understand possible etiologies.

Description of non-brachycephalic canine conjunctival microbiome before and after application of an antiseptic preparation.

OBJECTIVE: To evaluate canine conjunctival microbiome before and after an antiseptic preparation using aerobic culture and DNA sequencing. ANIMALS STUDIED: Six healthy non-brachycephalic dogs. PROCEDURES: Dogs randomly received povidone-iodine 1:50 dilution solution in one eye with the second eye serving as a control. Standardized volumes of solution, number of sterile cotton tipped applicators, and preparation times of 5 min were used. Aerobic culture and DNA sequencing samples were collected from inferior conjunctival fornices at baseline, immediately following, 24 h, and 4 weeks following antiseptic preparation. Aerobic culture data were evaluated using paired t-test and linear regression. Illumina platform was used to sequence bacterial DNA using primers to target the V4 region of bacterial 16S rRNA. Quantitative Insights Into Molecular Ecology (QIIME 2.0) was used to analyze data. RESULTS: Baseline aerobic cultures consisted of Bacillus (35%), Staphylococcus (30%), Streptococcus (20%), Moraxella (5%), Micrococcus (5%), and Simonsiella spp. (5%). No significant difference was detected in mean number of species cultured at baseline and following treatment (p = .465). Treatment, sample time, or interaction was not significant (p > .393). The most abundant phyla at baseline via DNA sequencing were Proteobacteria (57.04%), Actinobacteria (19.89%), Firmicutes (3.25%), and Bacteroidetes (5.5%). Alpha and beta diversity matrices at baseline and over time revealed no significant change in species richness or bacterial composition. Relative abundance of bacterial taxa did not significantly differ in treated or control eyes over time. CONCLUSIONS: Conjunctival bacterial flora identified differed between culture dependent and independent methods. The bacterial community remained stable over time after application of the antiseptic preparation.

Investigation of fluorescein stain-based tear film breakup time test reliability in dogs in a clinical setting.

OBJECTIVE: To determine intra- and interobserver reliability of a fluorescein stain-based tear film breakup time (TFBUT) test as performed in a clinical environment with and without administration of a topical anesthetic. ANIMALS: 21 privately owned dogs. PROCEDURES: A randomized study design was used. Two independent observers that commonly perform the TFBUT test in clinical practice read the same description of TFBUT. Observers performed TFBUT testing for each dog before and after topical administration of 0.5% proparacaine solution in 4 testing periods with a 1-hour interval between periods. Intraclass correlation coefficient (ICC) analysis was used to assess inter- and intraobserver test reliability. Linear mixed models were used to assess the main effects of testing period, observer, eye, and presence of ophthalmic disorders and their interactions on TFBUT. RESULTS: Mean TFBUT measurements performed by observer 1 and observer 2 were 5.9 seconds and 8.6 seconds, respectively, when adjusted for other effects in the model. Intraobserver ICC was poor for one observer and moderate for the other. Interobserver ICC was poor without use of topical anesthetic and slightly lower when anesthetic was used. Observer and testing period were each significantly associated with TFBUT; the measurements decreased and were more variable after multiple applications of fluorescein stain and proparacaine. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested tear film stability is negatively affected by topical administration of 0.5% proparacaine solution and repeated applications of fluorescein stain. The TFBUT test as performed in this study had poor to moderate reliability.