Ocular ultrasonographic and biometric features of European brown hares (Lepus europaeus)

The aim of this work is to assess the normal ultrasonographic features and dimensions of eyes in European hares. Corneal thickness, anterior chamber depth, lens thickness, vitreous chamber depth and eye axial length were measured by ultrasound in 40 healthy hares (Lepus europaeus), 20 males and 20 females, mean age of 5.5 months (range 2–15 months). The effects of sex, side, age and body weight on each feature were recorded. Results show that ocular dimensions were not affected by considered variables except for the lenses thickness and axial length that were correlated with age and body weight. Our study concludes that although ocular structures had similar feature compared to other species, the description of the characteristics of the eye of the European hare is important to widen the knowledge of a species not completely known from the normal anatomical point of view. The lens dimensions could have a predictive value in determining the age of young hares.