I had these beautiful fancy mice that I'd rescued from feeder bins at pet stores. Their names were Strawberry (red banded satin male) Umbra (black satin female longhair), Dawn (red and white), and Pretty Polly (cream satin). Strawberry was clearly the most beautiful mouse in the world, as evidenced by this picture (so ok, maybe not the most beautiful, but surely close).
http://www.rialian.com/strawberry.jpgUnfortunately, mice only live a short time - 2-1/2 years if you're really good with them, 1-1/2 years if you're average like me and give them pet shop food instead of organic hand-mixed grain and fresh produce. Umbra passed at about 13 months old, and then Strawberry a few months later - I think at about 15 months. Several months prior to that, Dawn and Pretty Polly also had passed. They were all pet shop rescues, so they probably weren't that strong. None of them were very tame, since I didn't raise them from babies.
One really weird trait about Strawberry's strain was the apparent ability to gender shift. When I first got him, I thought he was a girl. Then when his son Rosie was born, I thought Rosie was a girl (until, that is, he got some females pregnant and promptly turned into a boy at about age 6 months. I didn't realize it, but Dawn/Pretty Polly's strain also had the gender shifting trait, as I found out recently.
Fortunately for me, both strains had babies before they died so they wouldn't be lost. From Strawberry and Umbra's line came Ygraine, a beautiful black satin mouse who carried Strawberry's red banded gene. Before Strawberry died, I bred her back to strawberry and got three red banded females. One died of some sort of paralysis - never did find out what that was. The other one died of tumors. But Poppy lived. Meanwhile, from Dawn and Pretty Polly's strain, I had Sunflower and Dandelion. Sunflower died of tumors and Dandelion of unknown causes about 6 months ago - but before that happened, I allowed them to breed once, and they had Luna, Ramona, and Juno - three beautiful red satin females with big black eyes.
Unfortunately, soon after that, Juno died - so Ygraine, Poppy, Luna and Ramona were left (and are my pets now as we speak). Everything was going along normally - four girl mice were easy to take care of, since they don't smell like the boys do. But I was sad that none of them were boys and the strains would both die out. They are exceptionally beautiful mice, and I like to breed them once during their life times to perpetuate them. I told them I wished one of them was a boy. (oops).
One day I decided to introduce them to a male from the pet store. To my surprise, as soon as I placed this male with them, Ramona went NUTS, and attacked to kill. I was like, huh?? Females usually don't do that with males. I removed the offending dude immediately. Then I started noticing Boy Mouse Smell from the girl's cage, in which there was no boy mouse. I checked carefully but no sign of any maleness was to be found. Four girls, just like always. They're all really fuzzy mice, so checking for nipples, which is one way to determine gender in mice, was not an option. I couldn't figure it out. I told Ramona, "Please turn into a boy, since I really need you to be one - and then do your job and reproduce, dammit. What kinna boy are you?" (oops).
Subsequently, he obliged (sproing). I caught him mating with all the females about a week later. Ygraine is too old to reproduce now and also has a large tumor. Luna never really fully developed into an adult, she's a tiny, sterile mouse - she hasn't become pregnant (thank goodness). But to my delight, Poppy is very pregnant. I expect 8 or 9 little visitors shortly. This should be most fun. Of course, Mr. Ramona will get his own cage now that he's "done his job" and perpetuated my Magic Mouse line.
But I'm still spooked by the fact that Ramona was, for all intents and purposes, a GIRL, until I asked her to switch. It must be the lighting and environment change - I'd had them upstairs and brought them downstairs. That must be it, yepyepyep...