A few days ago my friend gave me her chicken (I think a Silver Laced Orpington) after her other chicken got killed by an opossum. It was shy and kind of hid for a couple of days and yesterday I noticed it was limping. I checked her foot and there is a sore on the pad and it is swollen. I am guessing it happened when the other chicken was attacked. Should I leave it alone? Clean it? Thank you!