Observations on Ocular Fundus of Primates, Anthropoids and Prosimians

Abstract

Since 1975, photographs on ccular fundus of over 23 species belonging to Anthropoidea and Prosimii were collected.

A portable fundus camera made by Kowa Co., Type RC-2, was used for regular and fluorescein or indocyanin green angiographies under the anesthetic condition of investigated primates. Narrow or other gelatin filters were used for above regular snap or angiography of retina.

Generally, figures of Anthropoid's fundus were in same pattern. Oval or round optic discs were fresh and milky in color, and clearly distinguished from surrounding tissue. Retina was well pigmented excluding Owl monkey in South America.

In Japanese Macaques, Macaca fuscata yakui was peculiarized by its all tesselated retina. Creamy colored optic disc, however, was clearly observed.

Macaca fuscata fuscata in western district of Japan Islands showed tigroid retina partially.

In young stage of Anthropoids, retinal surface was observed as vinyl coated and bad high reflex activity for inserted light.

In Anthropoid families, Aotus trivirgatus was unique in fundus figure. This nocturnal species showed brilliant right colored retina having high reflex for inserted light. Macula could not be observed in examined cases of this species.

In Prosimian families, nocturnal animals, Galago crassicaudatus and Nycticebus coucang showed well developed Tapeum lucidum. In the other hand, diurnal species, Demur catta had high reflex tapetal zone in retina. The latter could be thought as a sample of time gap of evolution and adaptation. In this Sub-Order, Tupaia glis, diurnal tree shrew showed exotic ocular fundus. Distribution of the retinal vessels was similar to some species of rodents. However, well developed optic disc of this tree shrew had (pseudo) physiologic cup in central zone. Macula could not be observed in investigated Prosimians.