Certain Factors Affecting the Incidence of Malpositions Among Embryos of the Domestic Fowl

FACTORS affecting the incidence of malpositions are of considerable practical importance as well as scientific interest. Embryos in malpositions are less likely to hatch than those in normal position, especially under adverse circumstances. Six malpositions are described in the literature and combinations of several of these occur. It would be possible to subdivide still further the data on position at hatching time but there is probably no rational advantage in doing so. The material presented in the present paper is classified only in the four malpositions described by Hutt (1929) and “other dead,” which includes the normal hatching position. These four malpositions are: I, head between legs; II, head in small end of egg; III, head under left wing; IV, beak away from air cell. The data presented indicate that malpositions I and III are of common origin, and that malpositions II and IV are also of common origin but . . .