DRUSEN-LIKE DEPOSITS IN THE OUTER RETINA OF JAPANESE-QUAIL

Histological examination of the outer retina of Japanese quail (Coturn ix coturnix Japonica) ranging in age from 4-48 months revealed the pre sence of drusen-like deposits which closely resemble those described i n primate and human retinas. At both light and electron microscopic le vels, these deposits were characterized by randomly distributed, granu lar and heterogenous materials. Larger deposits with pleomorphic inclu sions, often globular in shape, occurred more frequently in older quai l, particularly in males. An increase in the incidence and size of dru senoid deposits occurred with increasing age, with a greater rate of a ccumulation in males than in females. Previously, we have shown that r etinal pigment epithelial lipofuscin increases more rapidly with age i n female quail and that cumulative light damage is associated with inc reased lipofuscin in females but not in males. In the present study, n o increase in drusen-like deposits was observed in single light-damage d or double light-damaged retinas of either sex. Thus, lipofuscin and the frequency and size of drusenoid deposits do not appear to be direc tly linked, although both increase with age in both sexes.