Many dog owners seek veterinary assistance because their pet sheds excessively. You should remember that the natural development and growth of new hair is accompanied by the shedding of old hair. Shedding may be abnormal (excessive) if it results in obvious loss of the hair coat and bald spots. Abnormal shedding may be caused by bacterial infection. However, if the shedding is not accompanied by bald patches or symmetric hair loss, it is likely the shedding is just a stage in the natural replacement of the hair coat.