I have a female beagle, 17 months old, I have been running her in the field some, she developed a sore on her neck, just below her collar, it started out the size of a 50 cent piece, within a day, it enlarged to about 3 inches wide by about 5 long, then there is a smaller spot just about her shoulder. I washed it with mild soap, put peroxide on it, then put neosporine ointment on it, it now is just raw, all the hair also fell out in the area. I had some cefa 250 I started giving her, it has been 3 days, not healing yet, but no worse, what else can I do?
I recommend a visit to the vet. This could be ringworm which is a fungas. Good luck, vetcare