This type of relationship is extremely rare. There are only a few married couples of this type exist. Although vixens are a bit more wild than male foxes. In general, vixens are very tame and like the male foxes, they get along well with the mice.
To a male mouse, mating with a vixen feels good to him and it gives him a sense of confidence because the male mouse has successfully mated with a vixen. And once the couple has mated with each other, the vixen becomes more tame towards her mouse lover.
To a vixen however, mating with a male mouse is rather boring at first on the count of that her body is designed to be mated by a male fox and the anatomy of the male mouse is very different from the male fox. It's a wonder why vixens allow male mice to mate with them at all. That is, until the climax...the semen of the male mouse is very thick and they produce a lot of it. To the vixen, this feels good and this is why a vixen is willing to mate with male mice.
After about 7 or 8 weeks the vixen will give birth to anywhere from 4 to 12 young. Mouse semen also increases the fertility of the vixen. However, the increased fertility increases the amount of labor pains.
