Female Mice Avoid Male Odor from the Same Strain via the Vomeronasal System in an Estrogen-Dependent Manner.

Inbreeding avoidance is essential to providing offspring with genetic diversity. Females' mate choice is more crucial than males' for successful reproduction because of the high cost of producing gametes and limited chances to mate. However, the mechanism of female inbreeding avoidance is still unclear.

A healing period increases mini-implant stability in growing rats.

We assessed the stability of orthodontic mini-implants in young rats. Male rats with mean ages of 6 weeks (n = 16) and 20 weeks (n = 16) were divided into four groups (n = 8 each). In the 6- and 20-week immediate-loading groups, immediately after placement, mini-implants were exposed to an experimental traction force for 2 weeks.

Estrus cycle-related preference of BALB/c female mice for C57BL/6 males is induced by estrogen.

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.