Ophthalmic diagnostic testing and examination findings in a colony of captive brown pelicans (Pelecanus occidentalis)
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Published on: February 26, 2022
Kristen M O'Connell1, Tammy M Michau1, Jessica M Stine1
1Ophthalmology, BluePearl Veterinary Partners, Tampa, FL, 33614, USA.
Objective:
To establish reference values and report ophthalmic examination findings in a colony of captive brown pelicans (Pelecanus occidentalis).
Design:
Descriptive study.
Animals Studied:
Sixty-three captive brown pelicans in Florida were examined.
Procedures:
A complete ophthalmic examination including Schirmer tear test (STT), applanation tonometry, fluorescein stain, biomicroscopy, and direct and indirect ophthalmoscopy was performed. A-scan ultrasonography was performed to measure axial globe length (AGL), anterior chamber depth (ACD), lens thickness, and vitreal chamber length. Fifty-two adults and 11 juvenile pelicans with an age range of 4 months to 38 years were evaluated.
Results:
Twenty-nine pelicans (46%) had a normal ocular examination. Mean STT in normal pelicans was 5.45 ± 1.88 mm/min. Mean intraocular pressure (IOP) in normal pelicans was 10.86 ± 1.61 mmHg. One pelican was fluorescein positive unilaterally. Mean AGL was 20.70 ± 0.62 mm. Mean ACD was 3.38 ± 0.19 mm. Mean axial lens diameter (ALD) was 5.19 ± 0.23 mm. Mean vitreal chamber depth (VCD) was 12.15 ± 0.53 mm. Twenty-three pelicans (36.51%) had cataracts, 17 pelicans (26.98%) had vitreal degeneration, 18 pelicans (28.57%) had corneal disease, and seven pelicans (11.11%) had evidence of significant ocular trauma, which included collapsed anterior chamber or lens luxation.
Conclusions And Clinical Relevance:
To the author's knowledge, this is the first report of normal ophthalmic parameters and the incidence and type of ocular disease in a captive flock of brown pelicans. This information may aid in the diagnosis and treatment of brown pelicans with ocular disease.
