Yolk Cholesterol Levels Research Articles

The Effect of Sex-linked Barring and Rate of Feathering Genes, and of Stock, Upon Egg Yolk Cholesterol

TAYLOR (1960), after a comprehensive search of the literature, observed that “of all the structures of the egg, the yolk seems to be the least influenced by hereditary factors.” Current interest in cholesterol as related to human health has stimulated the study of hereditary and other factors which influence yolk cholesterol level in chicken eggs.Harris and Wilcox (1958) found significant differences in egg yolk cholesterol among dams in a Randombred population of Leghorns. Edwards et al. (1960) observed significant strain or breed differences in cholesterol content of the fat of eggs. The phenotypic correlation between yolk cholesterol and egg production in a randombred population from October through December was estimated by Harris and Wilcox (1963a,b). The correlation coefficient (r) for November cholesterol and for March cholesterol was the same, −0.17. Correlation coefficients between body weight in March and yolk cholesterol in November and in March were +0.15 and +0.13, .

The Effect of Dietary Cholesterol and Different Dietary Fats on Cholesterol Content and Lipid Composition of Egg Yolk and Various Body Tissues

THE effect of dietary lipids on the lipid composition of the egg and tissues of the hen has recently received much attention. The type or amount of dietary fat appears to have no effect on total lipid content of egg yolk according to Reiser et al. (1951), and Marion and Edwards (1962). Dietary fat also has very little influence on cholesterol deposition in the egg yolk (Reiser et al., 1951; Fisher and Leveille, 1957; Wheeler et al., 1959; Daghir et al., 1960; Edwards et al., 1962). However, when cholesterol is included in the diet of the hen, the egg yolk cholesterol level is increased according to the findings of Dam (1928), Budowski et al. (1961), Wood et al. (1961) and Harris and Wilcox (1963).Leveille and Fisher (1958) found that the iodine number of egg fat from hens receiving dietary corn oil was significantly higher than when animal fat or…

Effect of Dietary Cholesterol on Serum and Egg Cholesterol Levels over a Period of Time

THE influence of dietary cholesterol on the levels of serum and egg cholesterol of the laying hen was recently studied by Harris and Wilcox (1963) and the literature was critically reviewed. These workers found that after 11 days of feeding crystalline cholesterol to hens the serum and egg cholesterol levels were significantly increased. They interpreted their findings to suggest that laying hens are able to prevent a marked hypercholesteremia by excretion of cholesterol into the yolk. Since there is at least one report in the literature (Kurnick et al., 1958) in which no increase in yolk cholesterol was obtained when cholesterol was fed to laying hens, the possibility of time being a variable in these observations by various workers appeared possible.This study was conducted to determine the effect of feeding cholesterol to laying hens on serum and egg yolk cholesterol levels over a period of time. EXPERIMENTALSingle Comb…

Studies of Serum and Egg Yolk Cholesterol Level of Hens Immunized Against Newcastle Disease

Abstract In studies of biochemical patterns in blood, Agarwal (1956) observed an increase in plasma iron and a reduction of blood cholesterol, but little change in the end products of protein metabolism following experimentally induced rabies in sheep. Similar results were reported by Mondini (1955) in horses hyperimmunized against tetanus toxin. Contrary to these reports, Puntigam and Berger (1955), investigating serum cholesterol levels of healthy heifers used for the production of smallpox vaccine, observed that, within four days following inoculation, the esterified cholesterol rose by approximately 16 percent in two-thirds of the animals. Then a gradual drop in cholesterol level occurred and, between the 10th and 14th day after inoculation, a minimum value of 40 percent of the initial level was reached. Free cholesterol was affected similarly. Owing to the importance of cholesterol in many body functions and, in view of the frequency with which vaccination is used in modern prophylaxis…

Studies on Egg Yolk Cholesterol: 3. Effect of Dietary Cholesterol

THE earliest reports in the literature of dietary induced changes in egg yolk cholesterol were provided by Dam (1928 Dam (1929). By feeding free cholesterol (1 gm. daily), he obtained an elevation of about 20% in the yolk cholesterol level, and upon the feeding of 3 gm. of “cholesterylpalmitat,” he observed an increase in yolk cholesterol of from 8 to 16%, followed by a decline of about 12% upon cessation of the dietary source. Quite recently Leveille and Fisher (1958) and Combs and Helbacka (1960) demonstrated that diets containing 10% corn oil increased yolk cholesterol whereas 10% animal fat did not effect yolk cholesterol level. Wood et al. (1961) have shown a marked elevation in yolk cholesterol with the addition of 1% cholesterol to the diet and noted that the presence of 10% corn oil in the diet enhanced this increase. On the other hand, Kurnick et al. (1958) did not …