Central corneal thickness and intraocular pressure in captive black-footed penguins (Spheniscus dermersus).

Abstract

OBJECTIVE: To determine the central corneal thickness (CCT) by ultrasonic pachymetry and the effect of these values on the measurements of intraocular pressures (IOP) with rebound tonometry (TonoVet(®) ) in a captive flock of black-footed penguins (Spheniscus dermersus). Variations in CCT by age and weight, and variations in IOP by age were compared. ANIMAL STUDIED: Both eyes of 18 clinically normal black-footed penguins (Spheniscus dermersus) were used. PROCEDURE: The IOP was measured by the TonoVet(®) in both eyes of all the penguins. CTT measurements were performed 5 min later in all eyes using an ultrasound pachymeter. RESULTS: The mean IOP values ± SD were 31.77 ± 3.3 mm Hg (range of mean value: 24-38). The mean CCT values were 384.08 ± 30.9 μm (range of mean value: 319-454). There was no correlation between IOP and CCT values (P = 0.125). There was no difference in CCT measurements by age (P = 0.122) or weight (P = 0.779). A correlation was observed (P = 0.032) between IOP values and age. The coefficient of correlation was negative (ρ = -0.207). CONCLUSIONS: Ultrasound pachymetry has shown to be a reliable and easy technique to measure CCT in penguins. No correlation was observed between IOP and CCT values in this study. IOP showed a significant but weak decrease as age increased in the black-footed penguin.