Corneal sensitivity in healthy bovine calves. (27th March 2014) - Tofflemire, Kyle L.
Abstract Objective To evaluate corneal sensitivity as measured by the corneal touch threshold in healthy bovine calves. Animals Studied Twelve clinically normal male calves with predominantly Holstein genetics and a median age of 76.5 days (range, 67–92 days). Procedures Corneal touch threshold (CTT) of the central cornea was measured in both eyes of each calf using a Cochet‐Bonnet aesthesiometer. Results The mean ± standard deviation corneal touch threshold of all eyes was 1.33 ± 1.1 g/mm2 (range, 0.62–66.15 g/mm2), corresponding to a filament length of 34.56 ± 8.02 mm (range, 14–47.5 mm). There was no significant difference between fellow eyes. Conclusions Cochet‐Bonnet aesthesiometry was well tolerated in all 12 calves using a modified head restraint. Calves in this study may have a relatively sensitive central cornea compared to adult cattle and some other species; however, wide variation among individuals and eyes may be possible. Studies utilizing larger calf populations are necessary to establish reference ranges.