[Development and cell differentiation of the motor nucleus of the facial nerve of cattle].
The early development, cell-migration and cell-differentiation of the nucleus motorius nervi facialis were studied in 32 bovine embryos with a CRL of 1 to 53 cm by light microscopical techniques. The ventro-medial cell column, a transitory embryonic formation, can be regarded as the origin of the nucleus. From there migrating cells can be demonstrated up to a CRL of 2.7 cm. With 3.8 cm CRL the cells are confined to their definitive location. From 5 cm CRL onwards a subdivision into 4 subnuclei can be seen. By succeeding maturation processes the nucleus of fetuses with 53 CRL acquires the topographical and cellular appearance of mature animals. With the electron microscope the cell-differentiation of the early stages (2.5 and 3.6 cm CRL) was demonstrated. Additionally the ventro-medial cell column was studied. The vertical columnar organisation of the neurons of the nucleus facialis shows besides longitudinal orientated guiding structures the migration process which is taken place at a CRL of 2.5 cm. Synaptogenic cell contact are seen from 3.6 cm SSL. At this stage the migration of cells has come to an end.
Ruhrig
S
S
Institut für Veterinar-Anatomie, -Histologie und -Embryologie, Justus-Liebig-Universität, Giessen.
Hummel
G
G
Hild
A
A
Goller
H
H
D000818:Animals; D002417:Cattle / Q000196:embryology*; D002454:Cell Differentiation; D005154:Facial Nerve / Q000196:embryology* / Q000648:ultrastructure; D008854:Microscopy, Electron; D009046:Motor Neurons / Q000166:cytology* / Q000648:ultrastructure
Entwicklung und Zelldifferenzierung des Nucleus motorius nervi facialis beim Rind.