Anatomy and histological structure of Jacobson organ in male long-eared hedgehog (Hemiechinus auritus)

Jacobson or vomeraonasal organ (VNO) is an accessory olfactory organ that its function is to perceive pheromones. Structure of VNO was studied in 10 healthy mature male hedgehog. The head without mandible were fixed and decalcified. Nasal cavity was sectioned to five segments. Parafinized blocks and serial sections were prepared. Sections were stained using H&E and Masson's trichrom method. Anatomical results revealed that there were 9.6± 0.547 palatine folds in the roof of mouth. There was a bipartite and pad- like structure on maxillary incisive teeth. It began from the third incisive papilla to in front of fifth fold. Histological results showed that the shape of the organ tube was heart-like in initial part and its surface area was measured 0.313 mm2. Lining epithelium was stratified squamous epithelium in initial part and stratified or columnar epithelium in near fourth palatine fold. Two epithelial tissues were observed in fifth palatine fold. Pseudostratified columnar without cilia and goblet cell and stratified cuboidal epithelium. In adjacent of fourth segment, pseudostratified epithelium with small cilia was observed in medial part. Small cilia beyond neuroepithelilal cell which receive pheromones. Lamina propria and tunica submucosa was vascular loose connective tissue. Vessels were organized as erectile tissue. There were many nerve trunks and tuboloacinar gland in second end sections. Tuboloacinar glands were abundant serous firstly and mucous in end regions.