Scotopic electroretinography in fishing cat (Prionailurus viverrinus) and leopard cat (Prionailurus bengalensis).

Objective: To establish baseline normal scotopic electroretinograpic (ERG) parameters for two wild cat species: fishing cats (FC) and leopard cats (LC).

Animal Studied: Twelve normal, FC and eight LC kept in the Chiang Mai Night Safari Zoo, Thailand. The mean ages of FC and LC were 7.08 and 5.00 years, respectively.

Procedure: All animals were studied using a standard scotopic protocol of a portable, handheld, multi-species electroretinography (HMsERG).

Results: There were significant differences in the means of ERG b-wave amplitude of the rod response (Rod, 0.01 cd.s/m ), a- and b-wave amplitudes of standard light intensity of rod and cone response (Std R&C, 3 cd.s/m ) and b-wave amplitude of high light intensity of rod and cone response (Hi-int R&C, 10 cd.s/m ) with LC having higher amplitudes than FC. There was no significant difference in a- and b- wave implicit time except for the b-wave of Hi-int (P=0.03). No significant differences were observed in b/a amplitude ratios.

Conclusions: Data from this report provides reference values for scotopic ERG measurements in these two wild cat species. It showed that the normal scotopic ERG responses have some differences between the two species which might be due to the skull conformation, eye size or physiology of the retina.