Abstract
Twenty-eight hens which laid a yolkless dwarf egg are obtained from a flock of 17, 990 White Leghorn hens (1 1/2 years of age) throughout the experimental period of one month. Autopsy examinations on 20 hens revealed that the internal ovulation had taken place on the preceding day of the production of the dwarf egg. From the laying record on the remaining 8 hens following the production of the dwarf egg, it was found that the interval between the lay of dwarf egg and the succeeding normal egg was within a normal range.
The insertion of artificial yolk (AY) into the oviduct near the time of natural or induced ovulation resulted in the production of well calcified dwarf eggs similar to those naturally produced. However, the calcified dwarf eggs were not produced when the AY was inserted soon after the lay of the terminal egg of a clutch.
It is suggested that the production of yolkless dwarf eggs with shell seems to be associated with the incidence of ovulation.
