The morphology of the pecten oculi of the ostrich, Struthio camelus
Date
2006Author
Kiama, SG
Maina, JN
Bhattacharjee, J
Mwangi, DK
Macharia, RG
Weyrauch, KD
Type
ArticleLanguage
enMetadata
Show full item recordAbstract
The pecten oculi is a structure peculiar to the avian eye. Three morphological types
of pecten oculi are recognized: conical type, vaned type and pleated type. The
pleated type has been well studied. However, there exists only scanty data on the
morphology of the latter two types of pectens. The structure of the vaned type of
pecten of the ostrich, Struthio camelus was investigated with light and electron
microscope. The pecten of this species consists of a vertical primary lamella that
arises from the optic disc and supports 16–19 laterally located secondary lamellae,
which run from the base and confluence at the apex. Some of the secondary lamellae
give rise to 2 or 3 tertiary lamellae. The lamellae provide a wide surface, which
supports 2–3 layers of blood capillaries. Pigmentation is highest at the distal ends of
the secondary and tertiary lamella where blood capillaries are concentrated and
very scanty on the primary and the proximal ends of the secondary lamella where the
presence of capillaries is much reduced. In contrast to the capillaries of the pleated
pecten, the endothelium of the capillaries in the pecten of the ostrich exhibits very
few microvilli. These observations suggest that the morphology of the pecten of the
ostrich, a flightless ratite bird is unique to the pleated pecten and is designed to
meet the balance between optimal vision and large surface area for blood supply and
yet ensuring it is kept firmly erect within the vitreous
Citation
Ann Anat 188 (2006) 519—528Publisher
Department of Veterinary Anatomy and Physiology, University of Nairobi Institute of Anatomy, University of Bern, Baltzerstrasse Department of Anatomical Sciences, University of Witwatersrand Department of Biological Sciences, Kigali Institute of Education Institute of Veterinary Anatomy, Free University of Berlin, Koserstrasse