Here is the thing, you don't have to worry about rats until you get them. LOL It is better not to have them than to have to get rid of them though. A cover, if they couldn't get to the feed they would chew through the plastic. Several very pretty treadle feeders came out with plastic parts and ruined their reputation very quickly.
Might check if hantavirus is present in the rodents in your country. No cases until human contact happens or the doctors don't know to look for it.
Might check if hantavirus is present in the rodents in your country. No cases until human contact happens or the doctors don't know to look for it.