AUTORADIOGRAPHIC AND CYTOLOGICAL STUDY OF BLASTODERMAL CELLS IN TURKEY EGGS SUBJECTED TO EXTENDED PRE-INCUBATION STORAGE

¹ Department of Animal Sciences, Washington State University, Pullman, Washington 99163

An autoradiographic and cytological study involved blastoderms of Broad Breasted Bronze turkey eggs subjected to storage up to 21 days at 13° C. and 80% relative humidity. In one phase of the study, the blastoderms were treated with tritiated thymidine during storage; in the other phase, the blastoderms were first stored, then treated with T-H³ and, finally, incubated for 10 hours at 37.5° C.

Results indicate that:

1. The frequency of mitotic and necrotic cells in the blastoderms increased during pre-incubation storage.

2. Nuclei, labeled with T-H³, were found present in the blastoderms exposed to the isotope, both during and after storage.

3. The "aged" blastoderms, when incubated for 10 hours, showed a high incidence of necrotic nuclei, of nuclear fragmentation, of mitotic irregularity, and a decreased frequency of labeling with T-H³.

The conclusions reached are that:

1. The turkey blastoderm is physiologically active during extended storage at 13° C.: it exhibits evidence of some DNA synthesis and of undergoing limited mitosis.

2. The accumulation of cells blocked at metaphase during storage may be a major factor responsible for the subsequent moribundity of such blastoderms.