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Four hundred and eighty, sexed (White Leghorn) chicks were divided so that each sex was fed one of eight rations to determine the effect of sex, dietary cholesterol, and stearic, oleic, and/or linoleic acid on cholesterol deposition in blood, liver and aortic tissues. After 5 months on the dietary regimen, 3 cockerels from each of the rations were orally administered 100 mC. sodium-1-C14-acetate and 200 mC. cholesterol-1,2-H3 to determine whether body tissues contained cholesterol from endogenous or exogenous origin. After 5 months on the experimental rations it was observed that male birds had higher free cholesterol levels than did females. The addition of cholesterol (2%) and fatty acids (6%) to ration increased free cholesterol levels in liver and aorta. Cholesterol stored in livers and aortas occurs principally as free cholesterol while blood cholesterol was in esterified form. Cholesterol levels in both liver and aorta are primarily of endogenous origin.

INTRODUCTION SINCE its discovery in hog bile by Strecker (1862), the nutritional importance of choline has been increasingly recognized. It is considered by many nutritionists as a member of the B-complex group of vitamins and is a component of the widely distributed lecithin phospholipids found in egg yolk, liver, yeast, heart, brain and kidney (Best et al., 1932a, b, 1939; and Ewing, 1963). Choline also functions in methylation and demethylation reactions which are important in biological systems (Gillis and Norris, 1949; and Leach et al., 1966). It plays a vital role in growth promotion and as an antiperotic factor in chicks (Jukes, 1940a, b), and is involved in lipid mobilization in liver tissue of various animals (Atrom, 1958, 1960; Olson et al., 1958; Yoshida and Harper, 1960; Daghir and Balloun, 1961; Eric et al., 1965; and Rikans et al., 1965). To date, no quantitative requirement for dietary choline has been…

INTRODUCTION ONLY in recent years have we begun to realize the importance of choline as an essential factor in the normal growth and development of animals as well as in man. This is particularly evident in young animals and birds. Choline is a B-complex vitamin belonging to the lipotropic factor group in biological systems although some authors do not regard it as a vitamin (Ewing, 1963). Its involvement in methylation and demethylation reactions are becoming more evident as research of this metabolite progresses. Injections of methyl-14 C labeled methionine produced an activity for choline in rats of approximately 38% indicating that one probable acceptor of the methyl group of methionine for choline synthesis is ethanolamine or its dimethyl derivatives (Sterkol et al., 1953). Lust and Daniel (1964) while studying the biosynthesis of methyl groups of choline in vitamin B12 deficient Ochromonas malhemensis found that formate-14 C and formaldehyde-14 C incorporation into phospholipid choline…

DIETARY requirements for vitamin A are quoted in the literature as being from 500 to 3,000 International Units per pound of finished feed (Ringrose and Norris, 1936; Bearse and Miller, 1937; Taylor and Russell, 1947; Kurnick et al., 1961; Ascarelli and Bartow, 1963). Liver stores and blood levels have been used as evaluation criteria for this vitamin (Parrish et al., 1963; Squibb et al., 1958; Rubin and Bird, 1941; Olsen et al., 1959; and Tiews and Kring, 1962). In this investigation the effects of vitamin A, as well as the effect of vitamin E, were studied as they affected blood levels, liver storage and growth and the relationship between the circulating blood levels and liver storage of vitamin A. MATERIALS AND METHODS Two trials were run to determine the possible effects of 4 levels of stabilized vitamin A 2 palmitate on weight gain and blood and liver levels. The second trial …

SINCE it appeared that tungsten supplementation of breeder hen rations produced chicks deficient in molybdenum (Teekell and Watts, 1959), it was decided to use these chicks in evaluating the effect of adding various levels of molybdenum to the chicks’ diet. The anomalous response of the chicks from breeder hens fed supplemental tungsten and from non-supplemented hens which had been previously observed, raised some question as to the nature of the condition produced by the tungsten supplementation. The purpose of this study was to test the effect of molybdenum supplementation at various levels in a purified diet and a practical corn-soybean diet. Chicks from tungsten-supplemented and non-supplemented dams (control) were used in this study. EXPERIMENTAL The purified ration portion of this study involved 936 chicks in a series of 10 trials from the tungsten-supplemented hens and 854 chicks from non-tungsten supplemented hens. A purified cerelose-Drackett C-l assay protein ration was formulated …

METHIONINE is known to possess a dual metabolic function for protein synthesis and as a labile methyl group for one-carbon metabolism. McKittrick (1947) stated that choline and methionine could replace each other in a diet but only to the level of their essential increments. Quillin et al. (1961) revealed improved growth from choline additions on the lower methionine supplementation and likewise methionine supplementation resulted in improved growth with low choline rations; however, these rations were limiting in total methyl donors. Cardin (1967) attempted to determine if a preferential utilization of methionine for protein synthesis or transmethylation existed at various dietary levels of methionine using methyl-C-14-methionine and methionine-2-C-l4. He found transmethylation was occurring rapidly at all supplemental levels of methionine. Due to the widespread distribution of labeled methionine in the tissues, he could not postulate a true preference of methionine for protein synthesis or transmethylation. Methionine has been shown to be…

Two-week-old chicks were administered orally mixtures of vari ous kinds and amounts of amino acids. The effect of these amino acids on RNA synthesis was measured by the incorporation of tritium from uridine-5-3H into RNA of the chick liver. High levels of amino acids (300 mg) administered to chicks resulted in a decrease in RNA synthesis. Of the precursors of the purine ring tested (folie acid, glycine, glutamine and asparuc acid), only aspartA­cacid had any effect on RNA synthesis. It increased the synthesis of RNA. When tested at various levels, 20 mg of aspartic acid per chick promoted the highest amount of RNA synthesis whereas 40 mg of aspartic acid decreased the synthesis of RNA. Amino acid imbalances generally lowered both RNA and protein synthesis when compared to a completely balanced amino acid mixture. Of the imbalances tested by measuring the incorporation of carbon-14 from glycine-l-1'lC into both RNA and protein, a deficiency of tryptophan seemed to have the greatest effect. The data from these experiments in general indicate that amino acids will increase the synthesis of RNA when administered at recommended dietary intakes but will decrease synthesis of RNA when fed at excessively high intakes or as certain unbalanced mixtures. J. Nutr. 102: 987-994, 1972.