Figure 1.

Reproductive parameters. (A and B) Oestrous cycle length. The oestrous cycle was evaluated in Control and DM females at (A) 6–8 weeks and (B) 4–5 months of age by cytological analysis of vaginal washes. (C) Interval between mating plugs of DM females. DM females were caged with males and mating plugs were checked daily from 4 weeks to 6 months of age. Control littermates had a litter every 3 weeks and therefore, are not shown here. All DM females mated repeatedly throughout the study period. Half of the DM females had plug intervals of ~4 days (black triangle; consistent with the duration of the oestrous cycle), all DM females had interplug periods of 8–14 days indicative of pseudopregnancy (open diamonds), and all exhibited interplug intervals of 17–34 days (open circles) where they appeared pregnant but did not litter down (resorption of small litters occurs in mice). (A–C) Results are expressed as mean ± s.e.m. (D) Average ovary weight of Control (open circles) and DM (black triangles) females from 6 weeks to 1 year of age. Trend line of Control (solid line) and DM (broken line) ovary weight.