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Objective: To establish baseline ophthalmic parameters for an endangered, semi-wild population of healthy whooping cranes (Grus americana) (WHCR) and Mississippi sandhill cranes (Grus canadensis pulla) (SACR)., Animals Studied: Eighteen WHCR and 16 SACR., Procedures: Ophthalmic examination was performed by a single observer, followed by conjunctival swab collection for aerobic bacterial culture and measurement of tear production (phenol red thread test, PRTT) and corneal diameter (CD) as tolerated. Measurement of the axial globe (AG) length, anterior chamber (AC) depth, lens thickness, vitreous chamber (VC) depth, and pecten length was performed via ocular ultrasound (OUS) as tolerated., Results: Eyelid cicatrization (n = 1 WHCR), keratitis (n = 2 WHCR), incipient cataracts (n = 1 WHCR, n = 4 SACR), and uveal cysts (n = 1 SACR) were identified. Twenty-one bacterial species were cultured from SACR, while 18 bacterial species were cultured from WHCR. SACR under 6 months old had increased PRTT values compared to older SACR (p = .0432). AG length and VC depth of male WHCR were greater than in female WHCR (p = .0045 and p = .0008, respectively). WHCR less than 6 months old had greater AC depth and lens thickness than WHCR over 6 months (p < .001 and p = .0013, respectively). SACR less than 6 months old had greater AC depth and lens thickness than WHCR over 6 months (p < .0001 and p < .0001, respectively)., Conclusions: WHCR and SACR are amenable to complete ophthalmic examination. Age-related differences in PRTT in SACR, sexual dimorphism in WHCR, and age-related differences in AC depth and lens thickness in WHCR and SACR were identified., (© 2024 American College of Veterinary Ophthalmologists.)

Objective: To assess intraocular pressure (IOP) development in cranes and determine the impact of age, weight, species, head position, and sex., Animals Studied: Whooping cranes (WC) (Grus americana), and Mississippi-sandhill cranes (MSC) (Grus canadensis pulla)., Procedures: Chicks were manually restrained on days 1-3, 7, 21, 35, 60, 75, and 120 for routine examinations. IOP was opportunistically measured utilizing the Tonovet Plus® in D setting with the head above the heart (AH) and below the heart (BH). Values were also obtained longitudinally in adults (>120 days old) upon presentation in 1 year., Results: Intraocular pressure was highly correlated with age and weight in chicks. For every kilogram gained, IOP increased 2.46 ± 0.08 mmHg in WC and 2.66 ± 0.11 mmHg in MSC. Once hatched, IOP increased 1.13 ± 0.04 mmHg in WC and 0.87 ± 0.04 mmHg in MSC every 10 days. IOP was similar to adults at 120 days of age. In adult WC, mean IOP AH was 24.0 ± 0.4 mmHg, and BH was 27.9 ± 0.4 mmHg, there was a significant difference regarding head positioning and sex, females (25.3 ± 0.4 mm Hg) had lower IOP than males (26.5 ± 0.4 mmHg). In adult MSC, mean IOP AH was 20.7 ± 0.4 mmHg, and BH was 24.6 ± 0.4 mmHg. The difference between head positioning was significant., Conclusions: This study documents the correlation between IOP and weight or age during early development in cranes, as well as the importance of head positioning., (© 2024 American College of Veterinary Ophthalmologists.)

Background: Infectious bovine keratoconjunctivitis (IBK) is a common cause of morbidity in cattle, resulting in significant economic losses. This study aimed to characterize the bovine bacterial ocular surface microbiome (OSM) through conjunctival swab samples from Normal eyes and eyes with naturally acquired, active IBK across populations of cattle using a three-part approach, including bacterial culture, relative abundance (RA, 16 S rRNA gene sequencing), and semi-quantitative random forest modeling (real-time polymerase chain reaction (RT-PCR))., Results: Conjunctival swab samples were obtained from eyes individually classified as Normal (n = 376) or IBK (n = 228) based on clinical signs. Cattle unaffected by IBK and the unaffected eye in cattle with contralateral IBK were used to obtain Normal eye samples. Moraxella bovis was cultured from similar proportions of IBK (7/228, 3.07%) and Normal eyes (1/159, 0.63%) (p = 0.1481). Moraxella bovoculi was cultured more frequently (p < 0.0001) in IBK (59/228, 25.88%) than Normal (7/159, 4.40%) eyes. RA (via 16 S rRNA gene sequencing) of Actinobacteriota was significantly higher in Normal eyes (p = 0.0045). Corynebacterium variabile and Corynebacterium stationis (Actinobacteriota) were detected at significantly higher RA (p = 0.0008, p = 0.0025 respectively) in Normal eyes. Rothia nasimurium (Actinobacteriota) was detected at significantly higher RA in IBK eyes (p < 0.0001). Alpha-diversity index was not significantly different between IBK and Normal eyes (p > 0.05). Alpha-diversity indices for geographic location (p < 0.001), age (p < 0.0001), sex (p < 0.05) and breed (p < 0.01) and beta-diversity indices for geographic location (p < 0.001), disease status (p < 0.01), age (p < 0.001), sex (p < 0.001) and breed (p < 0.001) were significantly different between groups. Modeling of RT-PCR values reliably categorized the microbiome of IBK and Normal eyes; primers for Moraxella bovoculi, Moraxella bovis, and Staphylococcus spp. were consistently the most significant canonical variables in these models., Conclusions: The results provide further evidence that multiple elements of the bovine bacterial OSM are altered in the context of IBK, indicating the involvement of a variety of bacteria in addition to Moraxella bovis, including Moraxella bovoculi and R. nasimurium, among others. Actinobacteriota RA is altered in IBK, providing possible opportunities for novel therapeutic interventions. While RT-PCR modeling provided limited further support for the involvement of Moraxella bovis in IBK, this was not overtly reflected in culture or RA results. Results also highlight the influence of geographic location and breed type (dairy or beef) on the bovine bacterial OSM. RT-PCR modeling reliably categorized samples as IBK or Normal., (© 2023. The Author(s).)

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.

Wound healing differs significantly between men and women in a tissue-dependent manner. Dermal wounds heal faster in women whereas mucosal wounds heal faster in men. However, the effect of sex as a variable in corneal wound healing is largely unknown. The primary objective of this study was to test whether sex is a biological variable in corneal wound healing activated by the trauma or injury using an established in vivo rabbit model with male and female New Zealand White rabbits. Corneal wounds in rabbits were produced by a single topical alkali (0.5N Sodium hydroxide) application. Serial slit-lamp, stereo biomicroscopy, and applanation tonometry evaluated corneal opacity, anterior segment ocular health, and intraocular pressure (IOP), respectively, at various times during the study. Fourteen days after alkali-wound, corneal tissues were collected after humane euthanasia to examine cellular and molecular wound healing parameters. Quantitative PCR (qPCR) and immunofluorescence were used to quantify changes in the extracellular modeling protein levels of alpha-smooth muscle actin (α-SMA), Fibronectin (FN), Collagen-I (Col-I), and Transforming growth factor beta 1 (TGFβ1) involved in corneal healing. Hematoxylin and Eosin (H&E) staining was used to study histopathological changes in morphology and TUNEL assay to evaluate levels of apoptotic cell death. Male and female rabbits showed no significant differences in corneal opacity (Fantes score) or intraocular pressure (IOP) values (9.5 ± 0.5 mm Hg) in live animals. Likewise, no statistically significant sex-based differences in the mRNA levels of α-SMA (male = 5.95 ± 0.21 fold vs. female = 5.32 ± 0.043), FN (male = 3.02 ± 0.24 fold vs. female = 3.23 ± 0.27), Col-I (male = 3.12 ± 0.37 fold vs. female = 3.31 ± 0.24), TGFβ1 (male = 1.65 ± 0.06 fold vs. female = 1.59 ± 0.053); and protein levels of α-SMA (male = 74.16 ± 4.6 vs. female = 71.58 ± 7.1), FN (male = 60.11 ± 4.6 vs. female = 57.41 ± 8.3), Col-I (male = 84.11 ± 2.8 vs. female = 84.55 ± 3.6), TGFβ1 (male = 11.61 ± 2.8 vs. female = 9.5 ± 3.04) were observed. Furthermore, H&E and TUNEL analyses found no statistically significant differences in cellular structures and apoptosis, respectively, in male vs. female corneas. Consistent with earlier reports, wounded corneas showed significantly increased levels of these parameters compared to the unwounded corneas. Our data suggest that sex is not a major biological variable during active early stages of corneal wound healing in rabbits in vivo., (Copyright © 2019. Published by Elsevier Ltd.)