From the four-cell stage until the late blastoderm
stage, cell divisions become superficial, and nuclei can be seen as white yolk-less spots under transmitted light (Figs.
Given these observations above, this new culture system can maintain the stem-like character of stage X avian blastoderm
cells for a long term in vitro.
28(93.33%) chicks hatched on day 21 by themselves while 2(6.66%) did not hatch and when broken on day 22 they were found to be macerated early vascularised blastoderms
. Chicken embryos exposed to valproic acid in ovo showed increased mortality (pless than 0.001) and delayed hatching (pless than 0.001) (Table-2).
Eggs on which the blastoderm
was visible, were recognized as recently fertilized.
Segmental organization of the head in the embryo of Drosophila melanogaster: A blastoderm
fate map of the cuticular structures of the larval head.
The model to be used here refers to the expression pattern of transcription factor genes only in one developmental stage and only in one cell or a body region that shares an expression pattern, such as, for example, a set of nuclei in a part of a Drosophila blastoderm
expressing a specific subset of segmentation genes (Ingham 1988).
It does this by secreting protein-digesting enzymes that digest the outermost portion of the uterine wall, enabling it to bury itself there, with the side containing the inner cell mass, the "blastoderm
," coming into contact first.
Sabin, "Studies on the origin of blood vessels and of red corpuscles as seen in the living blastoderm
of the chick during the second day of incubation," Contributions to Embryology, vol.
Blastula stage started from fourth hour to twentieth hour after post fertilization, categorized with two separate layers of the blastoderm
, an external enveloping coating and a supplementary yolk syncytial layer.
Then eggs were placed in the racks with their blunt ends above and pointed ends below, and left in this position for 5 to 15 minutes to let the blastoderm
to rotate and come to lie above at the blunt end.
Development of embryos incubated by FPs was scored from stages 1 to 4: stage 1 (newly spawned), stage 2 (blastoderm
distinct, no eye development), stage 3 (eye development observed), and stage 4 (close to hatching).