Demodicosis in dogs: symptoms, diagnosis, treatment and prevention

A benign skin disease in most cases in healthy dogs, demodicosis is usually caused by the demodex canis mite , which is naturally present in the body of dogs. It is following a genetic abnormality that demodicosis occurs. It is therefore not a contagious disease.

Demodicosis in dogs symptoms

Left untreated, this ectoparasitosis can cause complications, especially in immunocompromised canines and elderly dogs. But puppies from birth to 12 months old account for almost 90% of canine demodicosis cases. After a difficult treatment that lasts several months, relapses are possible. Let's take stock of the different forms of this disease sometimes called demodectic mange , the symptoms, the treatment and see what is the solution that allows us to play the prevention card.

Demodicosis: symptoms that should alert

The main symptoms of demodicosis vary depending on the form of the disease.
  • Localized demodicosis of nummular form : it leads to the formation of small perfectly delimited skin patches, most often on the dog's head, neck, paws and chest, but can also affect any other part of the body. The affected areas lose all their hair. The skin is red , sometimes blackish or gray, covered with scales and comedones.
  • Localized demodicosis of diffuse form : the skin lesions do not have a very clear periphery. This form of demodicosis is characterized by a rancid odor , increased production of sebum (seborrhea), redness of the skin, scales and comedones, but the hair loss is less marked than in the nummular form. Diffuse demodicosis is most commonly diagnosed in Dobermans, Bobtails, Carlin, Westies, and Boxers.

Fortunately, the disease can very rarely spread and cause complications such as bacterial superinfection or pyoderma, with bluish gray skin staining, the appearance of multiple pustules and then crusts due to untimely scratching. This is called generalized demodicosis .

In the event of evolution, one can observe a pyodemodecia, namely a skin infection frequently caused by a staphylococcus. At this stage the dog's health deteriorates. The animal is dehydrated, is losing weight and is extremely tired.

There are other, less common forms of demodicosis. One mainly concerns burrows (demodicosis caused by Demodex injaï ). As for the others, it is Demodex pododermatitis which manifests itself in the dog's paws and Demodex otitis which affects the ears.

Demodicosis in dogs: diagnosis and treatment

To diagnose demodicosis , the veterinarian must perform skin scrapings and then study the samples under a microscope. This allows him to clearly identify the offending parasite. Sometimes a biopsy is necessary, as in the case of the Shar Peï or the Basset Hound, two dog breeds whose skin is particularly thick. The vet should also make sure the dog does not have an underlying disease . To do this, a blood test is required as well as any additional examinations that it deems necessary.

The treatment of demodectic mange is decided case by case. The veterinarian takes into account the form of the disease but also the age of the dog, its general condition, the possible underlying cause ...

Generally, in a dog which does not present any particular weakness, the disease having a strong chance of curing spontaneously, no treatment is necessary. On the other hand, when the animal is fragile or sick, or if it presents the generalized form of the disease, it can receive antibiotics , acaricides then a supplementation in essential fatty acids, in vitamin E. In parallel, a specific shampoo for acaricide baths is also recommended as is a suitable lotion . Note that herbal medicine can complement conventional treatment on the advice of the veterinarian, but should never replace it.

The duration of treatment for demodicosis in dogs can be a minimum of 2 to 4 months and to obtain good results it should not be interrupted under any circumstances. It requires regular monitoring and in particular at least two skin scrapings one month apart. The veterinarian can decide to stop acaricides only if these two samples prove negative . But it is up to him alone that this decision is made and the owner of the animal must strictly follow the practitioner's prescription. Treatment can only be stopped when complete recovery is proven.

Long and difficult, however, the treatment gives good results but does not prevent possible relapses . These are observed in 10% of dogs having followed a treatment, and more particularly in females during heat or during gestation. As for the means of preventing demodicosis in dogs , it is limited to sterilization. It is indeed not necessary to reproduce the bitches which are affected.