Longitudinal retinal functional evaluation using full-field electroretinography in New Zealand white and Dutch Belted rabbits with aging

Electroretinography (ERG) is pivotal in elucidating retinal function, yet investigations into the temporal dynamics of ERG signals in New Zealand White (NZW) and Dutch-belted (DB) rabbits remain scarce. This study presents a longitudinal assessment of retinal function in both NZW and DB strains. ERG recordings were conducted on four NZW and four DB rabbits at 2, 7, 15, and 24 months of age, encompassing both dark-adapted and light-adapted protocols at each time point. Quantitative analyses included assessment of a- and b-wave amplitudes, implicit times, and photopic flicker responses. Results revealed consistently stronger a- and b-wave amplitudes in NZW rabbits compared to DB rabbits across all time points. These stronger ERG responses likely result from increased effective light exposure at the photoreceptor level in NZW rabbits, rather than indicating intrinsic differences in retinal sensitivity. Over time, NZW rabbits showed a decline in visual function of the cone and postreceptoral systems, with the rod system less affected. In contrast, the visual function of DB rabbits initially improved at an early stage, followed by a slight decline after 15 months. The differences between the two strains may be attributed to the varying speeds of retinal maturation, melanin's absorption of light, and its protective effect against light-induced retinal damage. This dataset underscores the differential retinal characteristics between NZW and DB rabbits, shedding light on their distinct functional profiles.