Date of Award

Summer 2004

Document Type


Degree Name

Doctor of Philosophy (PhD)


Biomedical Sciences

Committee Director

Keith Carson

Committee Member

Alan Savitzky

Committee Member

Charles Morgan

Committee Member

David Scott


Several studies of the fine structure of the olfactory system of rodents have been conducted, but very little research has been done on members of the Insectivora. The olfactory systems of the northern short-tailed shrew, Blarina brevicauda, and the southern short-tailed shrew, Blarina carolinensis, were examined by light and electron microscopy. These shrews were live trapped in the vicinity of Norfolk, Virginia throughout all months of the year. Olfactory tissues were processed following standard transmission and scanning electron microscopy protocols. The olfactory system structures investigated included the olfactory epitheliumlmucosa (OEM), main olfactory bulb (MOB), accessory olfactory bulb (AOB), anterior olfactory nucleus (AON), olfactory tubercle (OT), and piriform cortex (PC). A new type of supporting cell, the light supporting cell, was observed in the OEM in Blarina . The MOB and AOB were laminated structures that were similar to other macrosmatic mammals. The AON was divided into typical mammalian subdivisions but the AON appeared at a significantly more rostral level within the MOB compared to other mammals. The AON was displaced in a dorsolateral direction in shrews. The trilaminar OT and PC had smaller cells compared to other small mammals. Light and electron microscopic data show that the olfactory system in Blarina differed from other small macrosmatic mammals and was well-developed.