Document Type

Open Access Presentation

Publication Date

Summer 8-23-2022


Purpose: Ophthalmic diagnosis in many avian species remains hindered by lack of normative values. This study aimed to establish normal ophthalmic parameters for select diagnostic tests in clinically normal Quaker parrots. Methods: Ninety-six captive Quaker parrots ages 8-18 years underwent ophthalmic examination to include assessment of neuro-ophthalmic reflexes, phenol red thread test, rebound tonometry, fluorescein staining, palpebral fissure length measurements, slit lamp biomicroscopy, indirect fundoscopy, and ocular ultrasound biometry. Results: Menace response, dazzle reflex, and direct pupillary light reflex were present for all Quaker parrots. Tear production (mean ± SD) was 13.3 ± 4.0 mm/15 sec and intraocular pressure (IOP, mean± SD) was 10.6 ± 1.4 mmHg and 6.0 ± 1.3 mmHg in the D and P rebound tonometer calibration settings, respectively. For IOP measurement, D and P calibration settings were not interchangeable, with the lesser variation of the D setting preferred in the absence of a gold standard. Ultrasound measurement of the anterior chamber depth increased with age and males had longer axial globe and vitreous lengths. Incidental adnexal and ocular lesions, identified in 36/96 (37.5%) of Quaker parrots, did not statistically affect the created reference data. Conclusions: This work provides reference values and clinical findings to assist with monitoring the health of wild populations and maintaining the health of captive Quaker parrots.


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This work was supported by Texas A&M College of Veterinary Medicine & Biomedical Sciences Veterinary Medical Student Summer Research Program (NIH T35OD010991-16). We wish to thank Debra Turner, Elizabeth Grimes, and Anissa Brooks for their assistance in the husbandry, collection, and handling of Quaker parrots.