Retinal Degeneration in Celestial Goldfish

Abstract

The celestial goldfish were systematically reared from fertilization for life, revealing developmental processes of retinal degeneration. The eyes began to protrude laterally at the age of 90 days, rotated antero-dorsally at 120 days, and thus the ‘celestial eye’ was completed. The retina developed to normal mature structure by the age of 50 days. No degenerative findings were revealed before the start of eye extrusion. The first morphological change, irregular distribution of melanin granules in the pigment epithelial layer and disorientation of the outer segments of photoreceptors, was detected at the age of 90 days. At 120 days, the pigment epithelial layer lost melanin granules at places and was occupied by phagocytes. Photoreceptor cells were destroyed, and phagocytes, containing melanin granules, appeared in the inner retina and/or choroid. The retinal degeneration started simultaneously with eye protrusion. The regular telescopic-eye goldfish have large, extended eyes as those of celestial goldfish, but they develop no retinal degeneration. Celestial goldfish seems to be an interesting new type of hereditary retinal degeneration in vertebrates.

Degenerative retinopathy in captive Atlantic menhaden, Brevoortia tyrannus (L.)

“…Retinal degeneration associated with anterodorsal displacement of the globe has been recently described in goldfish (Matsumura. Ohkuma & Honda 1981, 1982; Sakaue, Negi, Matsumura, Ohkuma & Honda 1987) and retinal pigment epithelial cell degeneration and retinal vascular tortuosity. thought to be due to renal insufficiency, have been recognized in carp (Murachi, Kohbara, Yamada, Sakurai & Nanba 1987).…”

The developmental changes of ERGs on spontaneous retinal degeneration of Celestial goldfish

“…As reported previously, the retinal degeneration is divided into three stages [2,3]. Until the age of 75 days the retina shows histologically normal development.…”

Study on Physiological and Biochemical Index of Blood and Vitreous Humor in the Celestial Goldfish (<em>Carassius auratus</em>)

“…So far, few studies have been done on celestial goldfish, much of which has focused on their genetics and body color [3][4][5]. Some reports have also suggested that celestial goldfish have a degenerated retina and weak vision [6,7], making them suitable as model animals for the study of human eye diseases [8]. Blood is an crucial component of the fish organism and immune system [9], and blood indicators have historically been emphasized by production practitioners and theorists, and are frequently used to assess the health, nutrition, and environmental adaptation status of fish [10], as well as water quality monitoring [11].…”