Where Does Skin Fungus Come From Scabs On My Cat's Neck. Why?

Scabs on my cat's neck. Why? - where does skin fungus come from

We have recently adopted a cat from a shelter / vet 's office. It was found in a field with her cubs, and was with them at least a month before I brought him home. She was still nursing, but has since dried up. They suggest that only 10 months or less. We noticed last week (we've had almost a month earlier) that a crust has a dry skull base. She does not care that we examined, and did not have itching or discomfort in any way. My husband worked for a few strike-breakers, and your normal skin tone with a red hue. There are small "plugs" of hair with scabs, who came from countries combined, but it has a white head or anything. No bleeding / draining them, BUI can not find where they come from. She went into a short day (3 or 4) heat and my cat neutered not ride it occasionally, but it is short and does not seem to affect. Perhaps a trifle? Your veterinarian should not be seen, but I wonder if an allergy, dry skin, or some kind of fungus. They came straight to the vet for us, and I am sure it is free of parasites (no fleas or flea dirt or combing). Ideas?