INVITRO DEVELOPMENT OF SECONDARY BLASTODISCS FROM DISPERSED BLASTODERM CELLS OF GALLUS-DOMESTICUS

The specific type of blastoderm cells with the capability of growing on the coverslip developed into the discoidal embryonic structures resembling those of avian species. The glass surface was apparently an initiator of differentiation into at least 3 types of cells specifically distributed in the blastodisc. Groups of structures formed were evaluated at 6, 12, 24 and 36 h to study the developmental pattern in vitro and to estimate the number of cells per structure. Microscopic examination of the area pellucida revealed that all 3 basic germ layers were established after 24 h of incubation in vitro. The 36-h stage was represented by bulky growth of mesodermal-like cells and changes in hypoblast layer where some of the cells degenerated and some were transformed to mesenchymal spindle-like cells.