Anatomical features of the conchae in the nasal cavities of the heads’ dog (A, C) and goat (B, D). Parasagittal sections (A,B) showing the structures of the medial nasal wall, including dorsal nasal concha (DNC), middle nasal concha (MNC), ventral nasal concha (VNC), ethmoidal concha (ET), frontal sinus (FS), nasopharynx (NP), cribriform plate (arrow) ,lamina transversalis posterior (LT), main olfactory bulb (MOB) and cerebral hemisphere (CH). Transverse frozen sections (C, D) at the lateral canthi of eyes showing ectoturbinates (EC), endoturbinates (ET), frontal sinus (FS), nasal septum (NS) and second molar teeth (2M).  

Histological features of the olfactory mucosae. Hematoxylin and eosin (H and E) stained sections from both dog (A) and goat (B) showing longitudinal sections of ethmoidal concha possess inner (I) and outer (O) epithelium and lamina propria (LP) with Bowman’s gland (G), olfactory nerve axon bundles(ON) and bone (arrows). The outer olfactory epithelium of both dog and goat (C, D) consists of supporting cells (S), olfactory receptor neurons (ORNs) and basal cells of horizontal (zigzag arrow) and globose (arrow heads) in shape. The ducts (D) of the Bowman’s glands (G) traverse through the olfactory epithelium (arrow). The inner epithelium (E, F) is olfactory (OE) in dog and respiratory (RE) with goblet cells (g) in goat. Cross sectional profiles in the lamina propria with larger size olfactory nerve bundles (ON) with blood capillaries (arrows) in dog (F) and smaller one in goat (G) contain the nucleus of the olfactory ensheathing cells (arrow heads). 

Immunohistochemistry staining for GFAP and synaptophysin of the olfactory mucosa from both dog and goat. GFAP immunoreactions are deeply reacted in the nerve fascicles (F) of the distal and apical parts of underlying lamina propria in dog and goat, respectively. At the junction (arrow) between the olfactory epithelium and the initial parts of the olfactory nerves, reactions are less intense in the goat more than the dog. Synaptophysin immunoreactions are clearly expressed in the ORNs (zigzag arrow) and in the olfactory nerve fascicles (F) through the lamina propria in both species. Synaptophysin give a strong a perinuclear cap-like arrangement reaction (arrow heads) also, in the goat give a strong reaction in the apical dendrites (arrow). Brown color indicates a positive reaction. Bar charts demonstrating area % of the GFAP and Synaptophysin positive expressions in the olfactory mucosa of both dog and goat. Data are showed as means ±SE (n=6), * refer to statistically significant differences (p ≤ .05). 

Ultrastructural features of the olfactory mucosa from both dog and goat (A-F). Features of the apical regions of the olfactory epithelium with cilia (zigzag arrow) that emanate from around the base in dog (A) and the tip in goat (B) of the olfactory knobs (k) and intermix with the microvilli (arrow heads) . A large olfactory axon bundle (C, D) with numerous fascicles (F) are wrapped and separated from each other by perineural-like sheath (arrows) of OECs processes with narrow (C) and wide (D) inter-fascicle separation and OECs nuclei (arrow heads). Cross section of the Bowman‘s gland acinus with serous cells (E) and mucous cells (F) with electron dense granules (G) and electron lucent coalescent granules (M) of the typical mucous cells (T) and electron dense granules (D) of A typical mucous cell (AT), lumen (L), nucleus (N).