Preliminary Anatomical Assessment of the Eye of the African Giant Rat (Cricetomys gambianus)

DOI: 10.18805/ag.D-183    | Article Id: D-183 | Page : 218-220
Citation :- Preliminary Anatomical Assessment of the Eye of the African Giant Rat (Cricetomys gambianus).Agricultural Science Digest.2020.(40):218-220
I.K. Peter-Ajuzie, I.C. Nwaogu, A.C. Ajaebili iheanyi.peter-ajuzie@unn.edu.ng
Address : Department of Veterinary Anatomy, Faculty of Veterinary Medicine, University of Nigeria, Nsukka.
Submitted Date : 10-08-2019
Accepted Date : 11-01-2020

Abstract

Eleven African giant rats were caught, bilaterally enucleated and the globes were routinely processed for light microscopy. Eye weight, vertical and horizontal corneal diameters, as well as vertical, horizontal and axial eye diameters were obtained from each globe. Observed external macroscopic ocular features were typical of mammalian eyes comprising cornea, sclera and attached extraocular muscles. The eye dimensions were however generally smaller than those of humans. The large mean corneal diameter to mean eye diameter ratio of 0.86 as well as the scanty retinal ganglion cells observed are associated with morphological adaptations for nocturnal vision. Pigments observed in the retinal epithelium suggests absence of tapetum lucidum, indicating a sub-optimal nocturnal visual capability. This study has provided scientific documentation of some ocular morphological characteristics of the giant rat and has shown that the eye of this species will be anatomically unsuitable for xenotransplantation in humans.

Keywords

Corneal diameter Cricetomys gambianus Ocular morphology Tapetum lucidum Xenotransplantation

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