Blastomycosis is a severe systemic infection caused by the fungal organism Blastomyces dermatidis. The organism grows in the soil in specific regions of the country, including the Missouri, Ohio, Tennessee, and Mississippi River valleys.

Dogs and humans are most at risk for infection; however, cats, horses, and other animals are occasionally affected. Because many tissues can be infected by the organism, the signs of the disease will vary.

Canine Demodicosis

Canine demodicosis is a type of mange that occurs when abnormally high numbers of a mite called Demodex canis multiply on the skin. This mite is normally present in small numbers in the skin of healthy dogs, but when a dog's immune system becomes weakened, the mites can overgrow and cause disease and inflammation of the skin.


Dogs and cats affected with Cheyletiella mites can either be intensely itchy or hardly itchy at all. They will frequently get a dry scale along their backs, which can spread to more severe and body-wide scaling. As the infection progresses, the itching becomes more severe. Patchy hair loss can occur due to severe scratching. Some cats may have very few signs other than self-induced hair loss from chewing/pulling out their fur. In humans, Cheyletiella mites cause a red raised rash on the arms, trunk and buttocks that eventually turns into a yellow-crusted area. Human infections usually resolve in 3 weeks if the host animal is treated.

Ear Hematoma

When an animal has a painful or itchy ear, it may swing its head about or scratch its ear to alleviate the discomfort. This behavior can cause trauma to the animal's pinna, or earflap, that can add even more irritation to the ear.

Ear Infections

An ear infection, or otitis, is an inflammation of the outer, middle, or inner ear canal. Most frequently, an animal will develop otitis in the outer ear that may worsen and spread into the middle ear. Once in the middle ear canal, the inflammation can move into the inner ear or, in cases in which the otitis has originated in the middle ear, the infection can instead progress outward to the external ear.

Ear Mites

Highly contagious, ear mites are a common cause of many ear problems in cats and, less commonly, in dogs. Ear mites are found in cats of all ages, but kittens tend to be infected more commonly. These mites can cause intense itching. Severe trauma to the infected area may result when cats scratch the irritated skin. Often, but not always, a dark, granular substance will be present in the ear canal of a cat with ear mites, and signs of irritation and itchiness will be evident.

Epitheliotropic Lymphoma

(1) generalized red inflamed and scaly skin-the skin maybe so flaky that the flakes appear to be shed in sheets; (2) loss of pigment and ulceration/crusting of the nose, lips and around the eyes-owners may notice a black nose slowly lose pigment to become completely depigmented; (3) single or multiple skin nodules; (4) thickening and ulceration of oral tissues.

Equine Atopy

Like humans, horses can be allergic to pollens, spores, and other allergens that appear in the environment seasonally, as well as substances found within the barn such as dust, mites, and animal dander. While people tend to respond to these various allergens by sneezing and developing watery eyes, while horses react by getting very itchy skin or developing hives. This leads to constant scratching and chewing which can cause trauma to the skin and extreme discomfort. Generally, symptoms worsen with age and can be controlled, but not eliminated.