1. Allergies: Allergies, such as food allergies, flea allergies, and environmental allergies, can cause itching, scratching, and hair loss.
2. Skin infections: Skin infections, such as bacterial or fungal infections, can cause hair loss and other skin problems.
3. Parasites: Parasites, such as fleas, ticks, and mites, can cause itching and hair loss.
4. Autoimmune diseases: Autoimmune diseases, such as lupus, can affect the skin and cause hair loss.
5. Cushing's syndrome: Cushing's syndrome, a hormonal disorder, can cause hair loss, among other symptoms.
6. Hypothyroidism: Hypothyroidism, a condition where the thyroid gland doesn't produce enough thyroid hormone, can lead to hair loss and other health problems.
7. Cancer: Certain types of cancer, such as lymphoma, can cause hair loss as a symptom.
8. Genetics: Some dog breeds are more prone to bald spots, such as the Chihuahua and the Greyhound.
9. Stress: Chronic stress can contribute to hair loss in some dogs.
If your dog is experiencing bald spots, it's essential to take them to a veterinarian for diagnosis and appropriate treatment. The vet can determine the underlying cause of the hair loss and recommend the best course of action to address it.