The short version
Alopecia is the partial or complete lack of hairs in areas where they are normally present. Hair loss is a sign and its underlying cause must be determined for the condition to be successfully treated. If a dog has hair loss and is also scratching the area excessively, the itching should be investigated first.
There are many causes of hair loss, which can be congenital (the animal is born with the condition) or acquired. Congenital hair loss may or may not be hereditary. It is caused by a lack of normal development of hair follicles. It may be apparent at, or shortly after, birth. Or, the dog may be born with a normal coat, and patchy or widespread hair loss occurs when the dog becomes a young adult.
Shedding
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.
Itching or pain is a common cause of acquired inflammatory hair loss. Diseases that commonly cause itching or pain include infections, parasites, and allergies. Skin cancer uncommonly causes hair loss. Friction may cause local hair loss, for example, poorly fitted collars. Rarely, excessive grooming may be the cause of hair loss in some dogs.
Signs of hair loss may be obvious or subtle, depending on the disease. Congenital or hereditary hair loss is commonly either symmetric (appearing similar on both sides of the body) or located in one area only. It is not usually accompanied by inflammation.
Frequently asked questions
Hair loss alopecia in dogs?
The Merck Veterinary Manual covers this in the article linked on this page. Alopecia is the partial or complete lack of hairs in areas where they are normally present. Hair loss is a sign and its underlying cause must be dete… If your dog is unwell, contact your veterinarian — this page is educational, not a diagnosis.
Why is my dog losing hair and getting bald spots?
The Merck Veterinary Manual covers this in the article linked on this page. Alopecia is the partial or complete lack of hairs in areas where they are normally present. Hair loss is a sign and its underlying cause must be dete… If your dog is unwell, contact your veterinarian — this page is educational, not a diagnosis.
Is my hair loss alopecia?
The Merck Veterinary Manual covers this in the article linked on this page. Alopecia is the partial or complete lack of hairs in areas where they are normally present. Hair loss is a sign and its underlying cause must be dete… If your dog is unwell, contact your veterinarian — this page is educational, not a diagnosis.