Protein Level as a Factor in Egg Production

THE protein requirement for egg production has been studied extensively in the past with somewhat variable results. However, when other factors such as egg size and maintenance of hen body weight were considered also, it was found in general that a ration containing approximately 15 percent crude protein (N×6.25) was most desirable, Heuser (1941). Recently, with the advent of the high energy ration, the adequacy of this level has been questioned. This doubt seems very logical because it is known generally that chickens and other animals eat to satisfy their energy requirements, and, thus an increase in energy content of the ration results in a decreased feed intake. Since Wilcox (1934) showed that protein used for egg production came entirely from the diet, it would appear that a hen on a high energy diet would consume less feed and, therefore, would require a higher percentage of protein in the diet . . .