Vitamin a and Carotene in the Nutrition of the Guinea Pig

Abstract

Simplified diets were devised, which when supplemented with lemon juice, ascorbic acid, and vitamin A or carotene were adequate for the growth of guinea pigs. These diets were used to produce vitamin A deficiency when vitamin A and carotene were omitted. The symptoms of vitamin A deficiency observed in the guinea pig were similar to those described in other species. These were typical xerophthalmia, weight loss, and death within a few days after the eye symptoms developed, usually 3 to 4 weeks after the young animals were placed on the deficient diet. Storage of vitamin A appeared to be restricted to the liver except for a trace in the kidneys. The liver stores were small except when the preformed vitamin was fed. Vitamin A appeared to be more than six times as effective for this purpose as was carotene. Daily amounts of 1.0 mg. carotene per kilogram for 38 days in depleted animals produced only a trace of liver vitamin A, whereas 2.0 mg. per kilogram daily for the same period resulted in storage that was just significant. The loss of these stores of the vitamin was rapid on lowered intake, 90% disappearing in 30 days.