How to Spot Mange in Dogs

While “mangy” is a term often used to describe animals in poor condition, mange is actually a specific skin disease in dogs caused by parasitic mites. Though several ectoparasites can cause skin issues, mange generally refers to infestations by two major mite species: Demodex and Sarcoptes.

Demodectic Mites

Demodicosis (also called demodectic mange or red mange) is caused by species of Demodex mites. These mites are species-specific, meaning they are not contagious to other dogs or humans.

There are two main species:

• Demodex canis – lives in hair follicles.
• Demodex injai – affects sebaceous (oil) glands closer to the skin surface.

Types of Demodectic Mange

Although all dogs carry some Demodex mites, only certain dogs develop mange due to an abnormal immune response.

• Localized demodicosis: Usually affects puppies; presents as 6 or fewer small bald, inflamed patches (commonly on the face or legs). Often resolves on its own.
• Generalized demodicosis: More widespread lesions across body regions, such as the ears, paws, or face.
• Juvenile demodicosis: Occurs in dogs under 2 years. Symptoms include hair loss, crusting, blackheads, swollen lymph nodes, and sometimes ear or paw inflammation.
• Adult-onset demodicosis: Seen in dogs over 2 years with no history of juvenile mange. May signal underlying illness like hypothyroidism, Cushing’s disease, or cancer.

Diagnosis requires a deep skin scraping by a vet. Treatments typically involve antiparasitic medications similar to those used for fleas and ticks.

Canine Scabies

Sarcoptic mange, or canine scabies, is caused by Sarcoptes scabiei var. canis, a highly contagious and zoonotic (transmissible to humans) mite.

Dogs typically catch it from infected pets, wildlife, or contaminated environments. Symptoms include:

• Intense, constant itching
• Crusting, red bumps, hair loss
• Commonly affected areas: ears, elbows, belly, hocks, and feet
• Signs of scratching trauma, like bleeding and scabs

Diagnosis can be difficult, as the mites are elusive. Vets may recommend a treatment trial if mange is suspected. Symptoms may temporarily worsen before improving.

How to Tell the Difference Between Mange and Other Skin Conditions

Not all skin issues in dogs are caused by mange. Several other conditions can closely resemble it, making proper diagnosis essential.

• Allergies (food or environmental) can lead to itchiness, redness, and hair loss, especially around the face, paws, and belly.
• Flea infestations can cause severe itching and scabbing, particularly near the tail and back legs.
• Fungal or bacterial infections, like ringworm or pyoderma, may create crusty, patchy lesions or pustules.
• Hormonal disorders, such as hypothyroidism or Cushing’s disease, can result in hair loss and skin thickening without much itching.

Because mange and these other issues can look very similar, a veterinary exam with skin scraping and possible allergy or blood testing is key to getting the right treatment. Never try to treat skin problems at home without knowing what you're dealing with; what works for one condition may worsen another.

Bottom Line

Mange is uncomfortable but treatable. If your dog has persistent itching, hair loss, or skin changes, consult your vet for proper diagnosis and treatment.