Our cat has a scar from an unknown source. We don't think she has been in any kind of fight or accident (she is always in an apartment and only has access to a balcony). We also think it is getting worse, it has been there for around a week. There was no red patch previously, just a tuft of missing hair. She does not seem to be in pain.
We are getting an appointment with our vet as soon as possible, the red patch has alarmed us. But does anybody know what this is, if it is not from a fight with another cat?
UPDATE: We took her to the vet and it turns out that she has an allergy and has been scratching it herself. They gave us a sort of body suit that she now has to wear for 10 days to allow it to heal. Plus an injection to stop the itching.