Effect of bilateral naris occlusion on neuronal Fos-immunoreactivity in the Pir and CoA of female and male ferrets killed at the end of this study after mating with an opposite-sex conspecific. The locations of the Fos counting regions (shaded areas) are shown for the Pir (A) and CoA (D). Photomicrographs of representative examples of Fos-IR neurons in these two brain regions are shown for a sham-occluded male (B, E) and a nares-occluded male (C, F). BA, Basal-lateral amygdala; Fx, fornix; IC, internal capsule; LA, lateral amygdala; LOT, lateral olfactory tract; Lv, lateral ventricle;MA, medial amygdala; OT, optic tract.Right graphs, Quantitative Fos data for the Pir and CoA, left (L) and right (R) hemispheres. The number of subjects in each group is given beneath each pair of bars for the CoA results. *p< 0.01, post hoc Student–Newman–Keuls comparisons with sham-occluded values for the same hemisphere. Data are expressed as mean ± SEM.