Incubation of Avian Eggs in an Inverted Position

INTRODUCTION Egg position during incubation has been considered an important factor in satisfactory hatchability and one which influences the incidence of certain embryo malpositions (Landauer, 1967). In particular, incubation of eggs in an inverted position, i.e., with the small end up (S.E.U.) has been reported to drastically reduce hatchability and to result in about a 60% incidence of embryos in Malposition 2 (head in small end of the egg) and 5 (feet over head) (Byerly and Olsen, 1931, 1933). Reports in the literature indicate hatchabilities as low as 36.4% (Byerly and Olsen, 1933) although recently El-Ibiary et al. (1966) reported a much less drastic reduction in hatch, using mostly eggs from S.C. White Leghorn pullets. Homma and Shumiya (1964), however, reported that in Japanese quail hatchability was sharply reduced in eggs incubated in an inverted position. We have compared the effects of incubating in the SEU position eggs from three…