I adopted two rats yesterday from my cousin who did not do her research before buying. I'm pretty excited, but I've noticed a few differences between the two. One has smooth fur and is curious. The other's fur sticks out, is rough, and he's shy and flinches. I know she was banging on the cage at least once and I could believe it went on longer, so maybe that's why? They're sweet, but a little nervous. I read a few things that rough fur could mean sickness. Please let me know!