It may be caused by exposure to certain chemicals or genetic factors as well as natural ageing and certain skin diseases. If the dog itself is older it will be considered to be due to natural ageing, for which there is generally no need for deliberate precautions or manipulation, it is a normal physiological activity. However, if there is also itching, redness and swelling of the skin at the white coat it is necessary to go to the hospital to check for skin diseases and other causes.
