Methods to distinguish male and female Dutch rats:

1. The scent glands of male rats are more obvious than those of female rats.

2. Male rats can see testicles after they reach sexual maturity, but female rats do not.

3. The nipples of female rats are larger and longer than those of male rats. There is a very obvious difference between female rats and male rats.

4. When in estrus, the testicles of male rats will turn red.

5. You can also look at the genitals. The male rat has a point above the Y, and the obvious penis can be seen. It will be exposed when you fiddle with it, but the female rat does not.