Stud male protection of implantation in food-deprived mice: role of pericopulatory olfactory experience

Abstract

Implantation failure in newly inseminated females induced by food deprivation for 48 hr beginning at 10.00 hr on day 4 post coitum was prevented by the presence of the stud male. However, a «familiar» male which had cohabitaded with the female for 7 days or more before pairing with the stud male did not show this protective effect. By contrast, a «familiar» male which had cohabitated with the female for 24 hr during the pericopulatory period provided protection to implantation in food-deprived females, comparable to that given by stud males. The results suggest that exposure to a male, whether the stud male or any other conspecific male, during and immediately after coitus enables the female to memorise the male-originating olfactory cues. This olfactory «memory» induces a luteotrophic effect in the female on re-exposure to the same male after mating. This accounts for the protective effect of the stud male and the «familiar» male on implantation in food-deprived females. The findings also provide additio...