I know that full grown rats are too big to work with mice. But don't male rats reach maturity befor they are too big for a large female mouse?

I have seen some pretty big breeder mice.

I just thought it would be a usefull rodent for problem switchers.

Any way it is just a hypothetical.

If the cross is possible there is no guarentee the the hybrid will be fertile. And they would probably be expensive, not redally available, and there for impracticle.

A
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1 BP
4 Cal Kings 3 alb 1 het
3 Alb Corn
1 Rev Alb Nelsons