Stud male protection of implantation in food-deprived mice: evaluation of the involvement of olfactory-vomeronasal systems.

The protection of implantation in food-deprived females provided by exposure to the stud males was not abolished following surgical ablation of the vomeronasal organ (VNO) from females. By contrast, stud males failed to protect implantation in food-deprived females made peripherally anosmic by intranasal irrigation with ZnSO4. The results suggest that the main olfactory system, and not the accessory olfactory system, is involved in the perception of the stud male-originating olfactory cue that protects implantation in nutritionally-stressed females. The findings also provide circumstantial evidence that the study male-originating olfactory cue involved in the protective effect is volatile (air-borne).