Red mange, scientifically known as demodectic mange, is a common but often concerning skin condition affecting dogs. Caused by a microscopic mite, Demodex canis, this parasitic infestation can lead to significant discomfort and visible skin issues. While the mite is a natural inhabitant of a dog’s hair follicles, an overgrowth, often triggered by a weakened immune system, results in the characteristic symptoms. This guide delves into understanding red mange, its diagnosis, and effective treatment options, focusing on providing pet owners with the knowledge to manage this condition.
Understanding Demodectic Mange (Red Mange)
Demodectic mange is an infestation of the skin by Demodex mites. These mites, typically found in low numbers on the skin of healthy dogs, are usually harmless. However, when a dog’s immune system is compromised, these mites can multiply rapidly, leading to a condition that manifests as red, inflamed skin and hair loss.
The primary culprit is usually Demodex canis, though other species like Demodex injai and Demodex cornei can also be involved. These mites are not a threat to humans and are generally not contagious between adult dogs with healthy immune systems. Transmission primarily occurs from a mother dog to her puppies during nursing, as their immune systems are still developing.
A dog with visible skin lesions indicative of mange.
Symptoms of Red Mange in Dogs
The clinical signs of demodectic mange can vary in severity. Initial symptoms often include:
- Alopecia (Hair Loss): Patches of hair loss, often starting on the face, around the eyes, or on the legs.
- Skin Scaling and Redness: The affected skin becomes red, irritated, and may be covered in scales.
- Papules and Pustules: Small bumps or pimple-like lesions can appear on the skin.
- Hyperpigmentation: The skin may darken in affected areas.
- Thickened Skin: Chronic inflammation can lead to the skin becoming thicker.
- Itchiness: While not always present, itchiness can occur, especially if secondary bacterial infections develop.
In more severe, generalized cases, dogs might exhibit lethargy, fever, pain, and draining wounds. Ear infections can also be a complication if the mites invade the ear canals.
Causes and Risk Factors for Red Mange
Demodectic mange typically arises when a dog’s immune system is unable to keep the Demodex mite population in check. Several factors can contribute to a weakened immune system:
- Puppies: Their immune systems are still developing, making them highly susceptible to mite overgrowth.
- Older Dogs: Age-related immune system decline or underlying illnesses can increase the risk.
- Underlying Medical Conditions: Chronic illnesses, hormonal imbalances, or other diseases that compromise the immune system can trigger demodectic mange.
- Genetics: Some breeds may have a genetic predisposition to immune system dysfunction.
It’s important to remember that exposure to Demodex mites alone does not cause mange; it’s the inability of the dog’s immune system to control the mite population that leads to the condition.
Diagnosing Demodectic Mange
Veterinarians employ several methods to diagnose demodectic mange, ensuring an accurate and timely treatment plan.
Skin Scrapings and Hair Plucking
The most common diagnostic tool is a skin scraping. A veterinarian will use a scalpel blade to gently scrape the skin deeply enough to reach the hair follicles, or pluck hairs at the root. The collected sample is then examined under a microscope to identify the presence of Demodex mites. Even a small number of mites in the sample is considered a positive diagnosis.
Cytology and Fecal Tests
Cytology can help identify secondary bacterial infections often associated with mange. In some cases, mites may be ingested by the dog while licking or chewing itchy skin, and thus can be detected through fecal flotation or fecal testing.
Skin Biopsy
In rare or complex cases, a skin biopsy may be recommended. This is typically reserved for dogs that are not responding to treatment or when the diagnosis remains uncertain after less invasive methods.
Red Mange Treatment for Dogs
The approach to treating red mange depends on the severity and extent of the infestation.
Localized Demodectic Mange
Mild, localized cases of demodectic mange, affecting only small areas of the body, often resolve spontaneously within one to two months without specific treatment. However, topical medications, such as those containing moxidectin and imidacloprid, can be used to accelerate healing and reduce discomfort.
Generalized Demodectic Mange
When demodectic mange is widespread across the dog’s body, more aggressive treatment is usually necessary. This typically involves miticidal medications, which kill the mites. These can be administered orally or topically and include:
- Ivermectin: A common and effective treatment, but crucially, dogs with MDR1 gene mutations should NEVER receive ivermectin, as it can be toxic. Genetic testing can identify this mutation.
- Milbemycin: Another effective oral medication.
- Doramectin: Used for treatment.
- Amitraz: A topical dip or wash.
- Isoxazolines: Medications like fluralaner (Bravecto), afoxolaner (Nexgard), sarolaner (Simparica), and lotilaner (Credelio) offer long-acting protection and treatment.
Miticidal therapy is continued until repeated skin scrapings or hair pluckings yield negative results for mites over consecutive tests.
Supportive Care and Secondary Infections
- Medicated Shampoos: Shampoos containing benzoyl peroxide are often recommended. These help to open and clean out hair follicles, allowing topical treatments to penetrate more effectively.
- Antibiotics: Secondary bacterial skin infections are common with demodectic mange due to inflammation and compromised skin. Antibiotic therapy may be necessary to treat these infections, sometimes before directly addressing the mites.
It is vital to discuss the risks and benefits of all medications with your veterinarian before starting any treatment.
Recovery and Prevention
With appropriate and timely treatment, most dogs recover fully from demodectic mange. The prognosis is generally good, especially when underlying health issues are managed effectively.
Breeding dogs diagnosed with generalized demodectic mange is strongly discouraged. The condition is believed to have a genetic component, and breeding affected dogs could pass this predisposition to future generations.
While demodectic mange is not typically transmitted between adult dogs, maintaining a strong immune system is key. Regular veterinary check-ups and prompt treatment of any underlying health concerns can help prevent recurrence. While environmental cleaning is not usually necessary for demodectic mange, monthly or tri-monthly parasitic preventatives against other common external parasites are recommended to protect your dog from fleas, ticks, and other types of mites.
For comprehensive parasite prevention and tailored treatment plans, consult your veterinarian. They can provide the best guidance for your dog’s specific needs.
