My baby mice are 3 weeks and 3 days old?

i have 4 of em and i need to know when i should separate them an how can i tell if they are male or female ive been handling them for a whie and they love to be held so holding them is not a problem. i looked at there bellies and none of them have nipples and there genatale {spelling su} : }area all looks the same???? how can i tell?My baby mice are 3 weeks and 3 days old?
You do need to separate them around now, otherwise you risk the males starting to breed.





Mice are usually easy to sex - but I'm very surprised you can't see any nipples (unless they are all males!)





Other ways to tell:





The ano-genital distance is much longer in males. When you look at them, you shoud see two points - the anus just by the tail, and a bit firther up either the vagina or the hole the penis extends from. The length of this gap is longer in males, but very short in females. It usually helps to hold two mice at a time so you can compare them!





Obviously at this age they will have fur, so you can also use this to help you. In males, the fur grows in between the penis and anus. In females it doesn't, so there should be a small bald line between the vagina and anus.





This site has some excellent photos showing you how to sec mice of pretty much any age: http://www.thefunmouse.com/info/sexing.c鈥?/a>





Hope this helps!My baby mice are 3 weeks and 3 days old?
Aww, must be so cute, the little mices.