Figure 7.

Schematic representation of the differences in the surface area of the nasal cavity and in the olfactory region between the animals most used in in vivo studies and humans. (A) rat; (B): dog; (C): rabbit; (D) sheep; (E) monkey and (F) human. The olfactory region (blue circles) occupies 10% of the nasal cavity (red rectangles) of rabbits, sheep, monkeys and humans, while in rats and dogs, it occupies most of the nasal cavity. Adapted from Refs. 6, 58, 59 with permission from Elsevier and Ref. 57 with permission from John Wiley and Sons.