Fungal diseases
One of the most common fungal diseases in dogs is ringworm, or dermatophytosis, an infection of the skin, hair, or nails. There are three fungal species that cause ringworm in dogs. About 70 percent of infections are caused by Microsporum canis, 20 percent by M. gypseum, and 10 percent by Trichophyton mentagrophytes. Signs include hair loss and scaling of the skin. Treatment for localized ringworm is not always necessary as the disease is self-limiting, but the cliinical course can be shortened by using topical miconazole or clotrimazole. Generalized infections, most commonly seen in immunocompromised dogs, can be treated with oral antifungal drugs such as griseofulvin or itraconazole. Infection can spread to humans.

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Blastomyces dermatitidis
There are several fungal diseases that are systemic in nature, meaning they are affecting multiple body systems. Blastomycosis, caused by Blastomyces dermatitidis, is a fungal disease that affects both dogs and humans, although it is only rarely zoonotic. It is found mainly in the United States in the Mississippi River and Great Lakes areas. Signs include weight loss, cough, fever, enlarged lymph nodes, draining skin lesions, blindness, and lameness. Because dogs are ten times more likely to become infected from the environment than humans, they are considered to be sentinels for the disease.
Histoplasmosis, caused by Histoplasma capsulatum, is a disease with a worldwide distribution. In the United States it is mainly found in the Mississippi and Ohio River areas, most commonly in bird and bat feces. Signs include weight loss, cough, fever, enlarged lymph nodes, and gastrointestinal symptoms. Coccidioidomycosis, caused by Coccidioides immitis, is found in arid and semi-arid regions of Central and South America, Mexico, and southwestern United States. Signs include weight loss, fever, cough, enlarged lymph nodes, and lameness.
from: wikipedia














