RT Journal Article
SR Electronic
T1 The elephant retina examined across a range of ages
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.01.20.427452
DO 10.1101/2021.01.20.427452
A1 James Freed
A1 Saskia Joyce
A1 Rachel Whalley
A1 Edward Purse
A1 Thomas L Ingram
A1 Lisa Yon
A1 Lisa Chakrabarti
YR 2021
UL http://biorxiv.org/content/early/2021/01/21/2021.01.20.427452.abstract
AB The effect of aging in the human retina has been well documented, as have the signs of age-related retinal disease. Comparative studies in animals allow us to further investigate how the retina ages in different species. The African bush elephant (Loxodonta africana) has a retina comparable to other mammalian species, but with some reported distinctive differences in retinal ganglion cell (RGC) distribution and type. This is a first survey of the retina of Loxodonta africana from individuals aged 2 months to 32 years old. Gross examination, H&E staining and cell counts were used to compare calves (0-5 years), juveniles (6-10 years), sub-adults (11-20 years) and adults (>20 years). Dorsal-ventral eye diameter was shown to be significantly greater with age, whilst no significant changes in photoreceptor number were found. Changes in retinal thickness differed from past findings in elephants and humans, with thickness decreasing, then increasing in adults. Various morphological differences were evident in the samples including the presence of nuclei in the outer plexiform layer (OPL), degeneration of the inner plexiform layer (IPL), interruptions in nuclei columns of the outer nuclear layer (ONL), and larger unidentified cells within the inner nuclear layer (INL). These are initial observations provide some baseline information for a species where this range of samples has not been described previously.Competing Interest StatementThe authors have declared no competing interest.