Time and Manner of Determination of the Malposition Head-in-small-end-of-egg

Abstract

THE data presented by Byerly and Olsen (1931) indicated that from 2 to 3.5 percent of all fertile eggs incubated contain at hatching time dead chicks with their heads in the small instead of the large end of the shell. In order to save the poultry industry the very large sums lost through this means, it is necessary to know the causes for this malposition and the portion of the incubation period during which those causes act. Byerly and Olsen (loc cit.) demonstrated that gravity is a very important factor in determining the hatching position of the chick embryo. The present experiments were designed to give information about the time of determination of the malposition head-in-small-end-of-egg and the mechanism of its determination. Data have been gathered coincidentally on the lethality of this malposition. MATERIAL AND METHOD Several lots of eggs were incubated for various periods in some one of the . . .