You may want to check all around the neck and the area right before the tail. I call it the crunchies when my guys have gotten but it is an allergic dermatitis. A steroid shot usually takes care of it. I do feral colony care and last summer carried fleas in to my guys, who don't go outside, and 9 of the 11 had allergic reactions. Needless to say they were not happy with momma.