answer:No. Rats are highly intelligent creatures, and they need to be able to interact with their environment in order to feel comfortable, confident and settled within it. They interact with their environment by sniffing it, mouthing it, grasping it… not by rolling around it in a ball. In a ball, your rat is more likely to become scared and frustrated than relaxed or entertained. The second reason not to is that hamster balls are too small for most rats, requiring rats to curve their spines when inside the ball, which can seriously injure them. More importantly, hamster balls have slits or holes in them through which a rat’s toe can easily be caught. Let your rat explore in a closed and secure room, or in a playpen.