Baseline histological and morphometric description of the retina in the Pied Crow (Corvus albus)

Abstract

The retina exhibited a well-organized multilayered structure typical of diurnal avian species, supported by a prominent hyaline scleral cartilage plate. The outer nuclear layer contained 3-4 rows of nuclei, consistent with the duplex organization of avian retinas. Total retinal thickness measured approximately 303 μm, with the ganglion cell layer measuring ~ 27 μm. NeuN immunolabeling showed strong nuclear immunoreactivity in the ganglion cell layer and moderate labeling in the inner nuclear layer. NeuN-positive neuronal somata in the ganglion cell layer ranged from 2.4 to 5.8 μm in diameter. These findings provide baseline histological and morphometric reference data for Corvus albus, contributing foundational information for future comparative and functional investigations.