Mange in Dogs

Overview

Mange a common skin disease in dogs and puppies that are strays, neglected, or abused. These dogs appear to be beyond hope—hairless, with skin covered in sores or with thickened, hard, crusty patches. Such dogs are often described as having skin that appears to have turned to stone. If your dog is itching like crazy or you notice patches of fur missing, your pup may have mange.

Mange in dogs is a type of skin disease caused by parasitic mites. Because mites also infect plants, birds, and reptiles, the term “mange” or colloquially “the mange”, suggesting poor condition of the hairy coat due to the infection, is sometimes reserved only for pathological mite-infestation of nonhuman mammals. Thus, mange includes mite-associated skin disease in domestic animals. But there’s no need to stress, mange in dogs is easily preventable and treatable.

Mange is readily transmitted between dogs by direct contact. Transmission by indirect contact may also occur. Clinical signs may develop anytime from 10 days to 8 wk after contact with an infected animal. The severity of the symptoms often depends on the type of mite causing the infection. Mange can be sarcoptic, demodectic, or notoedric depending on which species of mite is responsible.

Types of Mange in Dogs

In dogs, there are two major forms of mange, each caused by different mites:

• Sarcoptic Mange (also known as scabies)

• Demodectic Mange (also known as red mange or demodex)

Sarcoptic Mange

Sarcoptic mange is caused by a parasitic mite (Sarcoptes scabiei) that burrows just beneath the surface of the skin. These mites bury into the skin of healthy adult dogs and puppies, and feed on material in and on the skin. Sarcoptic mange is also known as scabies and is zoonotic, which means it is a disease transmissible from pets to people.

Sarcoptic mange is highly contagious to other dogs and humans. Although sarcoptic mites are not able to complete their life cycle on humans, they will cause severe itching until they die.

Symptoms of Sarcoptic Mange

Symptoms will generally appear about 10-days-to-8-weeks after contact with a dog carrying scabies. Typically, the first signs of the infection will be on the margins of the ears, chest, elbows, hocks, and belly. Untreated, they can quickly spread.

The most common symptoms of sarcoptic mange include:

• Extreme itchiness

• Redness and rash

• Thick yellow crusts

• Hair loss

• Bacteria and yeast infections

• Thickening of the skin (advanced cases)

• Lymph node inflammation (advanced cases)

• Emaciation (extreme cases)

Diagnosis and Treatment

Vets use skin scraping tests to diagnose sarcoptic mange, but they’re not too reliable. In fact, vets are able to confirm the presence of mites in only about half the cases of sarcoptic mange.

Often, a vet will treat a dog who has symptoms and just wait to see if they get better. Here are some ways they might treat it:

Your vet may give your dog medication and shampoo that kills mites.
Several different treatments may be used, as some mites have developed immunity to certain dips, such as invermectin, selamectin, lime-sulfur, and doramectin.

Vets may advise you to throw dog beds, collars, and harnesses in the washing machine or replace them.

Sarcoptic mange is highly contagious, so if you have several dogs and one appears to have it, treat them all — otherwise they’ll just keep passing it back and forth. Even after beginning treatment, dogs can be contagious for about a month. Keep infected dogs quarantined during this time.

Demodectic mange

Demodectic mange is caused by Demodex canis, a parasitic mite that lives in the hair follicles of dogs. Under the microscope, this mite is shaped like a cigar with eight legs.

Demodectic mange, sometimes just called ‘demodex’ or ‘red mange’, is the most common form of mange in dogs.
Demodectic mange is not contagious to other animals or humans. Demodex mites are transmitted to puppies from their mother during the first few days of life.

Since the mite is found on virtually all dogs, exposure of a normal dog to one with demodectic mange is not dangerous, as the immune system must be depressed for mange to develop.

A dog with demodectic mange usually does not itch severely, even though it loses hair in patches. The hair loss usually begins on the face, especially around the eyes. When there are only a few patches of hair loss.

Symptoms of demodectic mange in dogs

Demodectic mange can take three forms in dogs:

• Localised: Scaly bald patches can form on the dog’s face. It’s common among puppies. Consult your vet who will decide if treatment is necessary.

• Generalised:This is when more parts of a dog’s body are affected by the patchy, infected skin. Secondary infections can make the condition very itchy and your dog may smell. In most cases, generalised demodectic mange affects dogs under the age of 18 months that have an immune defect. In up to half of these cases, the immune system recovers and is able to surpress the parasites. When generalised demodectic mange occurs in older dogs, it is an indication of a potential underlying problem affecting immunity.

• Demodectic Pododermatitis:This is when the condition just affects the paws but it can be hard to treat and diagnose. Bacterial infections usually develop with this condition and the infection can often run deep through the tissue. Old English sheepdogs and shar pe is tend to be more prone to this.

Diagnosis and Treatment of Demodectic Mange in Dogs

Your veterinarian will take a skin scraping and look for mites under a microscope. In many cases, demodectic mange clears up on its own.

More severe cases may need to be treated long-term with medication and regular skin scrapings to monitor progress. For severe itching, treating your dog with a lime-sulfur dip (under the direction from your veterinarian) may provide relief.

Because demodectic mange is an indication of a weak immune system, your vet might also take steps to identify and treat any underlying illnesses that might be compromising your dog’s immunity.
Secondary bacterial infections must be treated aggressively with an appropriate antibiotic.

Antiparasitic therapy must be continued not only until clinical signs abate but also until at least two consecutive negative skin scrapings are obtained at one or more intervals.

Although some dogs respond rapidly, others may need several months of treatment. Recurrence within the first year of treatment is not uncommon.

As the sole prophylactic measure, dogs developing juvenile-onset generalized demodicosis should not be used for breeding.