Prevention of Cataract in the Progeny of Rats Fed a Maternal Diet Based on Vegetable Proteins 1

Abstract

Discussion and Summary

Each of the four nutrients found to be associated with a protection against congenital cataract formation in this study has been implicated previously as being necessary for normal lens health and development. Ferguson, Atkinson and Couch (4), and Ferguson, Rigdon and Couch (5) described a cloudiness in the central portion of the lens in embryos from eggs laid by turkey hens fed an all vegetable protein diet without added vitamin E. The diet consisted of soybean oil meal, ground yellow corn and ground milo with supplements of minerals and selected vitamins. Associated with the lens disorder was a high embryonic mortality. Supplementation with α-tocopheryl acetate (20 mg/lb) prevented the eye anomalies and restored normal hatchability rates. In mammals, a deficiency of vitamin E has been associated with resorption of the young. We have been able to find only two reports (6, 7) where eye abnormalities were reported as a consequence of a low intake of vitamin E by rats during gestation and in neither case were cataracts specifically noted.

The interaction of tryptophan and niacin in producing congenital cataract was studied by Pike (8). Her basal diet consisted of acid-hydrolyzed casein, 14.7%; sucrose, 15%; cornstarch, 42%; Brewer's yeast, 4.3%; salts, 2%; agar, 2%; Crisco, 15%; and cod liver oil, 5%, and was supplemented with 0.15 g of cystine and 10 mg of nicotinic acid/100 g diet. Quantities of tryptophan varying from 0.01 to 0.2% were added to the basal diet to determine the requirement for reproduction. Of 11 young selected at random from female rats fed diets containing 0.01-0.025% tryptophan, 7 had cataract. No cataracts were seen in 10 young when the female rats received a 0.2% tryptophan diet.