Pupillary Light Reflex and Menace Response in Neonatal Camel Calves (Camelus dromedarius)

Pupillary light reflex (PLR) and menace response are among the tests used in neurological and ophthalmic examinations in animals.

The intent of this study was to investigate the development of the PLR and menace response in neonatal camel calves.

Thirty healthy camel calves were studied after birth until the menace response and PLR were well established. The menace response was assessed by applying a non-tactile visual threat to each eye. The direct PLR was tested by shining a bright light into each eye and observing constriction of the pupil in the ipsilateral eye.

PLR was positive in all camel calves in the first test performed after birth. The first menace response developed at the age of 14 days, with 4 camel calves developing a menace response last, at 18 days of age. The menace response developed in most camel calves at 16 days old. The time to develop the menace response was not statistically different between the two sexes.

The PLR is present in camel calves immediately after birth. Menace response in camel calves develops within 18 days after birth.