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Objective: Feline herpesvirus 1 (FHV‐1) causes ocular surface disease in domestic cats. The purpose of this study was to assess the relationship between bacterial ocular surface microbiota and outcomes for cats with FHV‐1 ocular surface disease. Animals Studied: Twenty‐two shelter‐housed cats with confirmed FHV‐1 ocular surface disease. Procedures: Animals were grouped according to FHV‐1 shedding and ocular clinical scores following intervention: worsened outcome (WorOut, n = 11) or improved outcome (ImpOut, n = 11). Scoring and conjunctival sampling were completed on Days 1 and 8 of twice daily antiviral treatment. Bacterial DNA was extracted and submitted for 16S rRNA gene sequencing. Real‐time polymerase chain reaction was performed for selected bacterial species. Overall DNA concentration between groups was assessed. Results: Bacterial microbiota relative abundance composition was significantly different between ImpOut and WorOut groups (weighted UniFrac p =.006). Alpha diversity was significantly higher in the ImpOut group compared with the WorOut group (Shannon p =.042, Simpson's p =.022, Pielou's p =.037). Differences in the relative abundance of various phyla and species were detected between groups. Total DNA concentration was higher in the WorOut group compared with the ImpOut group (p =.04). Feline GAPDH (p =.001) and Bilophila wadsworthia (p =.024) copy number was significantly higher in the ImpOut group compared with the WorOut group. Conclusions: The results highlight the important relationship between the bacterial ocular surface microbiota and FHV‐1 infection outcomes in cats treated with antiviral medications. Low bacterial species diversity, higher overall DNA (presumed predominantly bacterial) load, and certain bacterial phyla/species were associated with poor outcomes for cats with FHV‐1 ocular disease. [ABSTRACT FROM AUTHOR]

Simple Summary: The ocular surface microbiome is altered in certain disease states. This study aimed to characterize the ocular surface microbiome of cattle with and without ocular squamous cell carcinoma (OSCC), a common eye disease in cattle. From a sample population of ten normal adult female cattle (twenty normal eyes) and nine adult female cattle with unilateral or bilateral OSCC lesions (ten diseased eyes, eight normal eyes), significant quantitative (real-time polymerase chain reaction (RT-PCR)) and relative abundance (16S ribosomal ribonucleic acid (rRNA) gene sequencing) bacterial microbiome alterations were identified based on disease status (normal or OSCC) and geographic location. Quantitative bacterial ocular microbiome discriminant analysis (DA) was capable of accurately categorizing samples based on disease status and geographic location. Quadratic DA, a method based on relatively inexpensive and readily accessible equipment, may be valuable for differentiating between normal and OSCC-affected cattle. The ocular surface microbiome is altered in certain disease states. The aim of this study was to characterize the bovine bacterial ocular surface microbiome (BBOSM) in the context of ocular squamous cell carcinoma (OSCC). The conjunctiva of normal (n = 28) and OSCC (n = 10) eyes of cows aged 2 to 13 years from two farms in Louisiana and Wyoming were sampled using individual sterile swabs. DNA extraction followed by 16S ribosomal ribonucleic acid (rRNA) gene sequencing and real-time polymerase chain reaction (RT-PCR) were performed to, respectively, assess the relative and absolute BBOSM. Discriminant analysis (DA) was performed using RT-PCR data, and relative abundance analysis was performed using 16S rRNA gene sequencing data. The 11 most abundant phyla in both normal and OSCC-affected cows were identified using 16S rRNA gene sequencing analysis. The relative abundance of Euryarchaeota was found to be significantly lower (p = 0.0372) in OSCC eyes compared to normal eyes. Relative abundance differences within and between geographic locations were also identified. Quadratic DA categorized samples as OSCC or normal with 100% sensitivity and 83.3–100% specificity. Relative abundance analysis identified relative BBOSM phylum alterations in OSCC. Quadratic DA can be used to accurately categorize BBOSM from normal and OSCC ocular surface samples. [ABSTRACT FROM AUTHOR]

This article discusses a case of orbital emphysema in a 5-year-old shih tzu dog following enucleation surgery. Orbital emphysema is a rare complication that occurs when air accumulates in the orbit due to the retention of conjunctiva within the orbit. The condition is more commonly seen in brachycephalic breeds. The diagnosis was confirmed through fine-needle aspiration and cranial imaging. Treatment involved surgical exploration and ligation of the nasolacrimal duct. The dog recovered well with no complications or recurrence. It is important to completely remove all epithelial tissues during enucleation surgery to prevent complications such as orbital emphysema. [Extracted from the article]

Enthusiasm for research describing microbial communities using next‐generation sequencing (NGS) has outpaced efforts to standardize methodology. Without consistency in the way research is carried out in this field, the comparison of data between studies is near impossible and the utility of results remains limited. This holds true for bacterial microbiome research of the ocular surface, and other sites, in both humans and animals. In addition, the ocular surface remains under‐explored when compared to other mucosal sites. Low bacterial biomass samples from the ocular surface lead to further technical challenges. Taken together, two major problems were identified: (1) Normalization of the workflow in studies utilizing NGS to investigate the ocular surface bacteriome is necessary in order to propel the field forward and improve research impact through cross‐study comparisons. (2) Current microbiome profiling technology was developed for high bacterial biomass samples (such as feces or soil), posing a challenge for analyses of samples with low bacterial load such as the ocular surface. This article reviews the challenges and limitations currently facing ocular microbiome research and provides recommendations for minimum reporting standards for veterinary ophthalmologists and clinician scientists to limit inter‐study variation, improve reproducibility, and ultimately render results from these studies more impactful. The move toward normalization of methodology will expedite and maximize the potential for microbiome research to translate into meaningful discovery and tangible clinical applications. [ABSTRACT FROM AUTHOR]

Purpose: To describe the optical coherence tomography (OCT) and fluorescein angiography changes in dogs with sudden acquired retinal degeneration syndrome (SARDS). Methods: Retinal OCT was performed on 10 SARDS dogs and eight control dogs. Tomograms were collected in four quadrants around the optic nerve. Measurements were collected from the photoreceptor layer, the outer nuclear layer, the outer retina, the inner retina and the whole retina thickness in all quadrants. Sodium fluorescein was injected intravenously and serial fundic photographs were collected for a 5 minute period post‐injection. Results: In all quadrants, the outer nuclear layer (dorsal temporal P = 0.0000, dorsal nasal P = 0.0001, ventral temporal P = 0.0002, ventral nasal P = 0.000) and outer retina (dorsal temporal P = 0.0001, dorsal nasal P = 0.0002, ventral temporal P = 0.0054, ventral nasal P = 0.0084) measurements were significantly decreased in SARDS dogs. The whole retina thickness was significantly decreased in the dorsal temporal (P = 0.0082) and ventral temporal (P = 0.0428) retina. There were no significant differences in the photoreceptor layer thickness or inner retinal thickness between SARDS and control dogs. All SARDS dogs had a loss of definition of all of the photoreceptor bands on OCT. Two SARDS dogs had multifocal small retinal detachments and one of these dogs exhibited fluorescein leaking at the detachment sites. Conclusions: The significant reduction in the outer nuclear layer and the loss of band signals in the photoreceptor layers in dogs with SARDS identified on OCT support the previous histopathology findings. Small detachments may occasionally be detected on OCT and they may leak fluorescein. [ABSTRACT FROM AUTHOR]

Objective: To characterize the bacterial community residing on the conjunctiva of clinically healthy dogs. Methods: Bacterial DNA from conjunctival swabs of 10 dogs with normal ocular examinations (both OD and OS, n = 20) was extracted, and 16S rRNA amplicons were sequenced using Illumina MiSeq 600. Resulting data were subjected to quality control steps, and analyzed for bacterial community richness and diversity, within‐ and between‐group dissimilarity, and relative taxonomic composition. Results: High‐quality reads (2.22 million bp) resulted in a mean of 159 068 sequences per sample. Bacterial community evenness and diversity was high when compared to other species, and did not significantly differ when samples were grouped by dogs or eyes. As expected, within‐dog samples were more similar than between‐dog samples. Taxonomic classification revealed that >95% of the community consisted of Firmicutes (34.9 ± 8.8%), Actinobacteria (26.3 ± 7.1%), Proteobacteria (26.2 ± 6.6%), and Bacteroidetes (9.4 ± 2.4%). Key members of the dog ocular surface microbiome, found in all dogs and corresponding to >25% of all identified OTUs (operational taxonomic units), were part of the Bifidobacteriaceae, Lachnospiraceae, Moraxellaceae, Corynebacteriaceae families. Genera previously thought to account for the majority of the core ocular surface microbiome in the dog (Staphylococcus sp., Streptococcus sp., and Bacillus sp.) were associated with only 2.63% of overall reads. Conclusions: This study shows the feasibility of conjunctival swabs and high‐throughput sequencing to profile the bacterial community structure of the canine ocular surface. A core ocular surface microbiome was identified for this canine population. [ABSTRACT FROM AUTHOR]

Abstract: A novel case of a canine odontogenic parakeratinized cyst (COPC) that resulted in exophthalmos and palatine, maxillary, and zygomatic bone erosion in a 5‐year‐old Chihuahua dog is reported. Final diagnosis was aided by cross‐sectional imaging (magnetic resonance imaging and computed tomography) and confirmed with histologic examination of the cyst wall. [ABSTRACT FROM AUTHOR]

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A 15-year-old, neutered male, Shih Tzu cross developed progressive corneal stromal thickening and vascularization of the right eye, and 5 months later, of the left eye. Both eyes became blind due to extensive corneal opacification and were enucleated. Light microscopic examination revealed a diffuse corneal infiltrate of neoplastic mesenchymal cells, and immunohistochemistry revealed diffuse cytoplasmic vimentin immunoreactivity and variable cytoplasmic and nuclear immunoreactivity for S100 in the neoplastic cells. Transmission electron microscopy revealed desmosomes between contiguous cells, thread-like cytoplasmic processes coated with basement membrane, extracellular bundles of collagen, and axonal degeneration consistent with features of a nerve sheath neoplasm. This is the first report of primary, bilateral corneal nerve sheath sarcoma in a canine. [ABSTRACT FROM AUTHOR]

Objective The objective of this study is to investigate the structural and functional ocular changes that develop in turkeys exposed to a photoperiod of 23 h of light (23L) compared with a photoperiod of 14 h of light (14L). Procedures Ten-day-old Nicholas heavy strain poults were exposed to either a 14L or 23L photoperiod. Between 16 and 18 weeks of age, equal numbers of turkeys per treatment group underwent ophthalmic examination (biomicroscopy, indirect ophthalmoscopy) ( n = 14), refractometry ( n = 20), keratometry ( n = 20), tonometry ( n = 20), and full-field electroretinography ( ERG) ( n = 14). Postmortem analyses included orbital magnetic resonance imaging ( MRI) ( n = 10) and light microscopy ( n = 24) at 18 weeks of age. Results Autorefraction revealed a median of −0.13 for sphere in both groups ( P = 0.69), which is approximately emmetropia. The radius of curvature of the cornea was significantly higher ( P = 0.0001) and the refractive power of the cornea was significantly lower ( P = 0.0001) in the 23L group. The astigmatic power was significantly greater in the 23L group ( P = 0.0001). Mean intraocular pressure did not differ between groups ( P = 0.085). Turkeys from the 23L group had significantly larger globes in nasotemporal ( P = 0.0007), dorsoventral ( P = 0.015), and anterioposterior ( P = 0.021) directions, and anterior chambers were more shallow ( P = 0.0002). ERGs revealed the 23L group to have lower a- and b-wave amplitudes and significantly lower cone flicker amplitudes ( P = 0.0008). Light microscopic examination revealed 23L turkeys to have significantly decreased numbers of nuclei in the outer nuclear layer ( P = 0.0001) and inner nuclear layer ( P = 0.0186), and decreased choroidal thickness ( P = 0.0008). The prevalence of cataract in the 23L group was significantly higher ( P = 0.001). Conclusions Exposing turkeys to a prolonged photoperiod induces significant ocular disease. [ABSTRACT FROM AUTHOR]

A 6-year-old female, spayed Collie was referred to the Western College of Veterinary Medicine for a 12-month history of a progressive right corneal mass. A superficial keratectomy was performed and histopathology revealed a corneal melanocytoma with complete excision. There has been no recurrence of the neoplasm to date (12 months). This is the first known report of an isolated corneal melanocytoma in a canine. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 7-year-old spayed female Labrador retriever-cross dog with blepharospasm, cloudy right eye and bilateral red eyes including the eyes being treated with anti-inflammatory medications and presence of ocular abnormalities indicating pigmentary uveitis.

The ocular surface microbiome is altered in certain disease states. The aim of this study was to characterize the bovine bacterial ocular surface microbiome (BBOSM) in the context of ocular squamous cell carcinoma (OSCC). The conjunctiva of normal ( n = 28) and OSCC ( n = 10) eyes of cows aged 2 to 13 years from two farms in Louisiana and Wyoming were sampled using individual sterile swabs. DNA extraction followed by 16S ribosomal ribonucleic acid (rRNA) gene sequencing and real-time polymerase chain reaction (RT-PCR) were performed to, respectively, assess the relative and absolute BBOSM. Discriminant analysis (DA) was performed using RT-PCR data, and relative abundance analysis was performed using 16S rRNA gene sequencing data. The 11 most abundant phyla in both normal and OSCC-affected cows were identified using 16S rRNA gene sequencing analysis. The relative abundance of Euryarchaeota was found to be significantly lower ( p = 0.0372) in OSCC eyes compared to normal eyes. Relative abundance differences within and between geographic locations were also identified. Quadratic DA categorized samples as OSCC or normal with 100% sensitivity and 83.3-100% specificity. Relative abundance analysis identified relative BBOSM phylum alterations in OSCC. Quadratic DA can be used to accurately categorize BBOSM from normal and OSCC ocular surface samples.