Abstract
The odor preference of female mice for male odor is reported to have cyclical variations in relation to the estrus cycle. Females prefer the odor of genetically dissimilar males to that of genetically similar ones but the causal relation between this preference and the estrus cycle has scarcely been investigated. The Y-maze test demonstrated that BALB/c females stayed for a longer duration near the urine of C57BL/6 males than that of BALB/c males when they were in metestrus, diestrus and proestrus, but not in estrus. The prolonged stay disappeared after ovariectomy, and administration of estradiol-17β restored the tendency. The present results suggest that the odor preference of BALB/c females for C57BL/6 over BALB/c males temporally changes according to the estrus cycle and that estrogen can be one of endogenous factors regulating this phenomenon.
