Symptoms of Canine Demodectic Mange: Key Indicators Exp

Canine mange mites, a type of mite that causes diseases in dogs, are known as Demodex canis. These tiny creatures make their home in the hair follicles and sebaceous glands, feasting on cell debris. Once these mites are separated from their canine host, they don't survive for long—only about an hour. The entire lifecycle of Demodex mites spans 25 to 30 days, completing its stages entirely within the host. The process is divided into four stages: the spindleshaped egg, the sixlegged larva, the eightlegged nymph, and the eightlegged adult. The exact mechanism behind diseases related to Demodex mite proliferation is still not fully understood. Generally, there are very few mites on most animals, but in infected animals, they can reproduce in vast numbers within the hair follicles.

Symptoms of Canine Demodectic Mange

Indications of demodectic mange on the skin include red spots, papules, pustules, bald patches, blackheads, dandruff, and excessive skin pigmentation. Itching may or may not be present.

Some dogs with demodectic mange may not exhibit hair loss but rather intense itching, leading to misdiagnosis as allergies. The affected areas are typically concentrated around the face and paws.

The primary clinical presentations can be categorized into two distinct types: juvenile onset (less than 2 years old) and adult onset (greater than 2 years old).

Juvenile Onset Demodectic Mange

The juvenile onset type can further be divided into localized and generalized demodectic mange. Prognosis and treatment vary from case to case. Certain dog breeds are more prone to the disease, including Afghan Hounds, Boston Terriers, Boxers, Dalmatians, Chihuahuas, English Bulldogs, Dobermans, American Bulldogs, German Shepherds, Old English Sheepdogs, Shih Tzus, American Staffordshire Terriers, and Great Danes.

Localized Demodectic Mange. In this scenario, only one area of the body is affected, as determined by skin scraping tests. This type of mange is usually benign and may resolve on its own, possibly involving localized redness and scaly hair loss. The affected areas are primarily on the face and paws. Additionally, bacterial infections may occur, leading to pustules.

The prognosis for localized demodectic mange is generally good, as over 90% of affected dogs may resolve spontaneously within 3 to 8 weeks.

Generalized Demodectic Mange. This type involves lesions in multiple areas of the body. Dogs with footpad mange are classified as having generalized mange. This type of mange has breed predispositions, with breeds like Bull Terriers, Bulldogs, Boston Terriers, Beagles, Collies, Dobermans, Boxers, Dachshunds, Dalmatians, Shih Tzus, Lion Dogs, and Lhasa Apsos being more susceptible. This form of mange is more severe than localized, and affected dogs may have a genetic predisposition to disease.

Recurrences are common, but the prognosis is still favorable. However, up to 50% of cases may resolve spontaneously without antiparasitic treatment if secondary bacterial infections are effectively managed, as bacteria may have immunosuppressive effects. Even if the disease resolves without treatment, whether the dog is male or female, it is advisable to undergo sterilization surgery.

Adult Onset Demodectic Mange

Demodectic mange is often secondary to another disease or a side effect of immunosuppressive therapy. Diseases commonly associated with adult onset demodectic mange include endocrine disorders (such as hypothyroidism and Cushing's syndrome), metabolic diseases, and cancers (such as lymphoma). Longterm treatment with steroids can also trigger demodectic mange, which is the most common cause of adult onset mange.

The prognosis for adult onset demodectic mange depends on the nature of the underlying disease. In some cases, up to 50%, diagnosis may not reveal any underlying condition, as demodectic mange may be the first sign of an immunosuppressive issue.