I agree with seasonal flank alopecia. My white bully had pink bald spots, and neighbor's tan bully had dark spots when seasonal flank alopecia kicked in. No antibiotics, steroids cured this. Holistic approach is 3 mg. Melatonin capsules sprinkled over her food in the morning and hair regrowth within 60 days. I kept her on this maintenance regime her entire life and never had recurrent seasonal alopecia. Melatonin is used to treat human alopecia and clinical research results are positive.I have the same issue with my bully. Took him to vet did scrapping for mange but not that. Vet said seasonal alopecia. Sure enough for the last 3 years every spring his flank hair will fall out and than grow back in May. Hair is darker where it falls out.
I have to agree with the seasonal comings and goings of hair loss though there was no real pattern to when it occurred. She'd lose some hair in patches...never bothered her...it'd grow back...she lose it again, it'd grow back again. But when we moved to Vegas several years ago it stopped.If the skin looks black where the hair loss is, it is seasonal aloepecia. The hair usually eventually grows back. Sometimes it stays dark and thinner. Some give melatonin. It is a pretty normal thing for a bullie. No meds will help.