Table 1 Carnegie stages and gestation age in the model bat C. perspicillata
Carnegie stage (CS) | Bat day of gestation | Mouse equivalent limbs | Mouse equivalent craniofacial | Key events |
|---|---|---|---|---|
CS16 | E50 | E12.5 | E14.5 | Craniofacial prominences completely fused Undifferentiated mesenchyme in medial midface Meckel’s cartilage as circular condensation Posterior cranial base cartilage begins to organize |
CS17 | E54 | E13.0 | E15.0 | Thickening of presumptive leaf-nose Lateral nasal capsule cartilage thickens Mesenchymal thickenings of olfactory turbinates Tooth development similar to mouse (thickening) |
CS18 | E60 | E13.5 | E15.5 | Dorsal ventral expansion at the resting zone of basisphenoid Resting zone formation in presphenoid Palatal shelves begin separation of oral and nasal cavity Meckel’s cartilage is rod-like across length of mandible Tooth development similar to mouse (tooth bud) |
CS19 | E64 | E14.0 | E16.0 | Cranial base fully connected along the anterior–posterior aspect of head Lateral nasal capsule fuses with medial nasal septum. Palatal shelf fusion Dermal papillae and induction of the sensory vibrissae. VNO as an epithelial tube with thicker sensory epithelium in its ventromedial side Leaf-nose bud increases in size as lancet development begins |
CS20 | E70 | E14.5 | E16.5 | Hypertrophic chondrocytes appear in the posterior basisphenoid Proliferation begins in the presphenoid |
CS21 | E75 | E15.0 | E17.0 | Hypertrophic chondrocytes appear in anterior basisphenoid Ossification begins in the posterior basisphenoid |
CS22 | E80 | E15.5 | E17.5 | Hypertrophic chondrocytes in anterior presphenoid Ossification in presphenoid Olfactory tract into olfactory epithelium |
CS23 | E85 | E16.0 | E18.0 | Continued growth |
CS24 | E90 | E16.5 | E18.5/P1 | Canine tooth appositional stage |