There might be a couple of reasons for this, you probably would be the best one who can judge the exact reason or else see a doctor.
1. Normal shedding cycle
3. Low in body vitamins
4. Liver issues
2. You can supplement with Yogurt/Egg/Meat.
3. Multivitamin syrup: A-Z syrup(human), Verol / Proviboost.
4. Liv 52
5. Bulfo shampoo / Anti-tick Collar
*In all situation give him/her Sancoat or Velcot.
Hope it helps.