The reason your dog is itchy and smelly may be from:
Lack of Regular Grooming
All dogs require regular grooming. Dogs with curly, silky or long coats must be brushed daily. If your dog is not groomed properly his hair may become matted. Feces, urine and debris can be trapped in the matted fur which can cause his skin to get irritated and infected. Flies can also lay eggs in the dog’s dirty, matted fur and cause a maggot infestation (fly strike).
Skin Infections
Your dog may have a yeast or bacterial skin infection. Many skin infections are driven by allergies such as flea allergic dermatitis, food reactions and environmental allergies. Common environmental allergens include trees, grass, pollen, mold spores, dust mites, cockroaches and detergents.
Infected Wound, Bite or Laceration
An untreated wound, bite or laceration can become infected. The infected area may develop an abscess and pus. The skin will have a foul odor.
Ear Infection
The smelly odor may be coming from your dog’s ears. A bacterial or yeast infection in your dog’s ears will cause a bad smell, itchiness and excess ear wax. Dogs with pendulous ears are most predisposed to get ear infections due to the lack of ventilation.
Seborrhea
Seborrhea is a skin condition that causes the sebaceous glands of the skin to produce too much sebum. Dogs with seborrhea have a strange odor that may become worse if a secondary skin infection occurs. Seborrhea can be triggered by hormonal imbalances (such as under-active thyroid disease or Cushing’s disease), poor diet, humidity, allergies and parasites. Seborrhea is more commonly diagnosed in the Cocker Spaniel, West Highland White Terrier, and the Basset Hound breeds.
Parasites
While parasites such as fleas, lice and mites do not create an odour, they cause intense itching. The dog can lick, chew and scratch to the point that they develop secondary skin infections.