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Objective: To determine the chronic effects of oral cannabidiol (CBD) use on tear production, intraocular pressure (IOP), and concentration of CBD in tears of healthy dogs. Animals Studied: Eighteen healthy research Beagles. Procedures: This was a masked, placebo‐controlled, randomized prospective study. Eighteen dogs were randomly assigned to three groups (six dogs per group) based on daily dosage of oral MCT oil (placebo), CBD 5 mg/kg, and CBD 10 mg/kg. Schirmer tear test (STT‐1) and IOP were measured twice daily (7 am and 7 pm) every 4 weeks for 36 weeks. Week 36 tears were collected and analyzed for CBD concentrations (ng/mL) using liquid chromatography/mass spectrometry. A mixed linear model was used as the statistical method and p‐value <.05 was considered significant. Results: No significant differences were found between placebo vs. 5 mg/kg vs. 10 mg/kg for STT‐1 or IOP (AM and PM). CBD was detected in 10 out of 11 (91%) viable tear samples receiving 5 mg/kg or 10 mg/kg dosages. One sample in the 5 mg/kg group had inadequate tear volume for analysis. The CBD concentration in tears was at or below the lower limit of quantification in placebo group, 4.12–11.2 ng/mL for the 5 mg/kg group, and 6.22–152 ng/mL for the 10 mg/kg group. Conclusions: Long‐term administration of oral CBD in healthy research beagles demonstrates a favorable safety profile regarding ocular tolerability. Oral CBD administration does not appear to affect tear production or IOP over a 36‐week period. This is the first canine study positively identifying concentrations of CBD in tears following oral administration. [ABSTRACT FROM AUTHOR]

An approximately 26‐year‐old, suspected female, red‐tailed hawk (Buteo jamaicensis) was presented with a history of chronic ocular changes of the left eye likely secondary to blunt trauma resulting in blindness and phthisis bulbi. Ophthalmic evaluation of OS revealed a large intraocular mass, 3+ aqueous flare indicating anterior uveitis, and severely decreased intraocular pressure measuring 5 mmHg. Ocular ultrasound revealed an abnormal, spherical shaped and hyperechoic lens, as well as hyperechoic material or a mass lesion in the posterior segment. An enucleation procedure was performed, and histopathology of the eye revealed no signs of neoplasia but instead intraocular osseous metaplasia with bone marrow and adipose tissue replacing the lens. Similar mass lesions were found in the retina and choroid. Multiple fractures in the scleral ossicle and cartilage correlated the intraocular lesions with a blunt traumatic event. A bioresorbable disk of porcine small intestine submucosa (BioSIS Vetrix®) was incorporated to relieve tension during closure. The graft sloughed during healing process, revealing a healed wound underneath. The BioSIS was not incorporated into the wound as designed but may have facilitated healing. This is the first report of intraocular osseous metaplasia in a raptor and the use of BioSIS Vetrix® with enucleation in an avian species. [ABSTRACT FROM AUTHOR]