My husband and I recently took in two young female guinea pigs named Cookie and Zoe. About two days ago I noticed a small dry flaky patch (smaller than a pencil eraser) above Cookie's eye. Overnight, the dry patch became quite large, lost hair, and has horrible looking scabs. What might cause this? She doesn't seem itchy and there are no other areas of hair loss or scabbing. I am making an appointment with a vet who has experience with exotic pets.