ERG Evaluation in Equidae: Horses vs Donkeys

Despite the small number of animals, the analysis of the ERGs parameters performed has allowed to show that there are differences between the two Groups. The ERG parameters, obtained by photopic or scotopic stimulation, show great amplitudes variability in the waves measured. This high variability can be attributed to changes in the retinal illumination. In photopic environment, the I-max average values are obtained for the two groups, by intensity of between 3 cds/ m2 and 0,9 cds/m2. That confirms the Photopic Hill is present in equines.. In scotopic environment, the ERG obtained by low-intensity stimulation after twenty minutes (T20) of retinal adaptability, both groups have reached average values of bwave superimposed. This shows that the retinal scotopic adaptometry (SA) was obtained and it seems there are no differences in the number and activity of the rods in both groups. To the author knowledge, this project provided the first electroretinogram evaluation in healthy donkeys by ERG full field in animals maintained in gaseous anesthesia, using mixture of oxygen and isoflurane.