Reference values for selected ophthalmic diagnostic tests and ophthalmic examination findings of donkey (Equus asinus ragusanus)

Purpose: To establish reference values for Schirmer tear test 1 (STT1), intraocular pressure (IOP) with applanation tonometry (TonoPen-Vet) and to describe ocular diseases in a popu- lation of Equus asinus Ragusanus. The data obtained were related with age. Methods: Eighty eyes of forty donkeys of different age and gender were investigated in Catania (Italy). A full ophthalmic examination was performed. In the presence of ocular diseases, findings were documented. Pedigree analysis of donkeys affected by cataract was performed. The median values of STT1 and IOP between adults and foals were compared using Mann- Whitney test. Significance was defined as P ≤ 0.001. Results: Twenty eyes (20/80-25%) of donkey foals and sixty eyes (60/80-75%) of adults were examined. Age range was 2–6 months for foals and 4–13 years for adults. The median values of STT1 and IOP in foals were higher than in adults (STT 1 P = 0.0002, IOP P = 0.0009). The prevalence of ocular abnor- malities was 22.5 per cent (18/80 eyes). Older donkeys were more likely to have ocular pathology. Clinical abnormalities included: conjunctival foreign bodies (1/18 eyes-5.55%),