The Effect of Composition of Diet Upon Weight of Eggs

THE addition of animal fat to the diet of laying hens has been reported to increase the weight of eggs (Hochreich et al., 1958). The design of this experiment did not allow these workers to determine whether the increase in egg weights was due to increased energy level of the diet or to the addition of the animal fat. However, Orr et al. (1958) reported that the addition of fat to a laying diet did not affect size of eggs, while Berg and Bearse (1957) reported that increased energy content of the diet resulted in increased egg weight. Jensen et al. (1957, 1958) reported that an unidentified factor was necessary in order to obtain maximum egg size; and that yellow corn was a source of this factor. Shutze, Jensen and McGinnis (1959) found that corn oil, safflower oil, and wheat germ oil contained the unidentified nutritional factor necessary for maximum…