I keep my two guinea pigs in a shed outside. They have a hutch which they are shut in at night but they have a big enclosure they go in all around the shed all day. Only trouble is I’ve discovered rats in there, and I know they could hurt the pigs so I’m making plans for the pigs moving to a place in my land that’s safer. I’m just concerned that the rats could’ve spread disease to my pigs. Are there any signs I should be on the look out for?!