Identifying Parasitic Skin Disease in Dogs: Symptoms &

Signs and Symptoms of External Parasite Infestations in Dogs

Scabies mites are the most common and challenging parasites to treat, often causing canine skin diseases. Demodectic mange is a hereditary condition that can recur after hormonal changes during reproduction or mating. It may also be triggered when the immune system is weakened. Symptoms typically include no significant itching, skin exudation, crust formation, and wrinkle development.

This condition predominantly affects the head, eyelids, and extremities. The symptoms of mange mites are severe itching and eczematous dermatitis, primarily occurring on the face, ear flaps, and ventral side of Chihuahuas. Ear mites are characterized by ear itching and brownish discharge from the ear canal.

Firstly, dogs are prone to three main types of mites: scabies mites (highly contagious), demodectic mites (more stubborn and often found in longhaired dogs), and ear mites. Each type presents with different symptoms:

1. Scabies Mites

More commonly seen in puppies and can be quite severe. They first appear on the bridge of the nose, cheeks, ear roots, and armpits, eventually spreading throughout the body. Initially, the skin may appear slightly red, followed by small red pustules, then blisters. When the blisters burst, the yellow, oily discharge dries and forms scaly crusts. The affected area becomes intensely itchy, causing the dog to scratch excessively, leading to severe hair loss.

2. Demodectic Mites

There are two types of demodectic mites: scaly and pustular:

① Scaly Type

This type is characterized by dandruff on the eyelids and lower eyelids, forehead, lips, neck, elbows, between toes, bald spots, and distinct hairline boundaries. It is accompanied by mild skin redness and dandrufflike scales, rough and cracked skin, and some dogs may develop small pustules. The skin may appear pale but is not itchy.

② Pustular Type

This type usually presents as small red bumps on the inner side of the thigh and lower abdomen, which may turn into small pustules within a few days. In severe cases, the dog may develop large red and white bumps on the inner side of the thigh, accompanied by a distinctive odor and itching. The dog may show extreme discomfort. If demodectic mites are heavily infested, they can cause a systemic skin infection, hair loss, pustules that break open into ulcers, and may lead to bacterial infections or even death.

3. Ear Mites

Ear mites are highly contagious and reside in a dog's external ear. They produce a large amount of lipid secretion and lymph exudation, leading to secondary ulceration in the later stages. The itching can become quite intense, and the dog may occasionally scratch its ears, shake its head, or pull at its ears, possibly crying out in pain. In severe cases, the dog may rub its ears against objects, causing bleeding in the ear canal. The ear canal may have brownishblack discharge and epidermal hyperplasia. The dog's ears may feel a noticeable pressure and pain, causing them to refuse ear examinations. Sometimes, the dog may turn its head towards the more severe side. Secondary bacterial infections may lead to purulent otitis media or otitis externa. In more severe cases, it may cause encephalitis, affecting the brain's nerves.

For the complete information on canine parasitic skin diseases, to ensure a better quality of life for your furry friend, we hope dog owners will regularly deworm their pets, maintain good hygiene, bathe them frequently, and seek veterinary care or consult online veterinary doctors if your dog shows any signs of skin disease.