In rodents, social and reproductive behaviors critically depend on chemical signals, including sexual pheromones that have been suggested (but not demonstrated) to be rewarding. In this work, we analyze this issue by studying the chemoinvestigatory behavior of adult female mice (without experience with male-derived chemicals) toward 1) the synthetic odorant citralva, 2) bedding soiled by differ...

To optimize the procedure for testis tissue xenografting, we grafted 2, 4, 8, or 16 small fragments of immature porcine testis tissue under the back skin of immunodeficient castrated mice (n = 10 mice/group). At 8 months post grafting, the graft recovery rate did not differ between groups; however, not only the total but also the average graft weights were higher (by approximately 12-fold and a...

Male and female mice castrated during the first 7 weeks of life and implanted with cancer at later periods show a resistance definitely higher than do intact animals of the same age. This increased refractiveness is evident at 3 months after the operation but is more pronounced at 8 months to a year. Even castration in early adult life seems to increase the refractory state to later cancer inoc...

Boar taint is an unpleasant odor that can be found in pork and pork products from male pigs (and occasionally, to a lesser degree, in castrates and females). Compounds contributing to boar taint include androstenone, a pheromone, biologically related to testosterone and produced in the testes, that has biological meaning to the adult boar and sow during reproduction. Sows express a willingness ...

Sexual reproduction in animals requires close interactions with the opposite sex. These interactions may generate costs of reproduction, because mates can induce detrimental physiological or physical effects on one another, due to their interest in maximising their own fitness. To understand how a male's presence influences aspects of female physiology implicated in reproductive costs in mice, ...

Intense exercise leads to accumulation of the inducible member of the 70-kDa family of heat shock proteins, Hsp70, in male, but not female, hearts. Estrogen is at least partially responsible for this difference. Because androgen receptors are expressed in the heart and castration leads to decreases in calcium regulatory proteins and altered cardiac function, testosterone (T) or its metabolites ...