CASE REPORT OF INFECTION DIAGNOSIS OF EQUINE DERMATOSIS IN RIO DE JANEIRO STATE, BRAZIL Ana Cristina Passos de Paiva Bello a ∗, Arildo Pinto da Cunha a, Romário Cerqueira Leite a , Nelson Rodrigo da Silva Martins, Paulo Roberto de Oliveira a, Antônio Cândido Cerqueira Leite Ribeiro b, Luisa Nogueira Domingues a, Eduardo Bastianetto a, Carolina Maria Vianna de Freitas c, Ricardo Canesso Dalla Rosa a, Patricia Bossi Leitea, Rebeca Passos Bispos Wanderley a Introduction: The equine skin diseases usually have been responsible for economical losses in equine production either directly or indirectly. Description of the case: In this case report, three equines with same father, crossbred (Crioula x Breton) living in the Rio de Janeiro State, Brazil, were diagnosed with the presence of dual infection, bacterial and fungal, causing wounds spread throughout the animal body. The specific symptoms are itching and loss of hair, the equines scratching themselves until developing bloody wounds. Skin lesions appear as crust-like scabs affecting much of the body. Irritated Skin with hair loss was observed too. The diagnosis was made through the collection of samples of matted tufts of hair. The crusts samples were macerated and submitted to Gram staining. The samples were also cultured for identification of fungal infection. It was identified then, by optic microscopy, the presence of Dermatophilus congolensis bacteria species and fungus colonies growth of Trichophyton sp. The treatment recommended was the application of Streptomycin 70mg/kg and three times iodine solution 1% baths. Discussion: Two of the animals recovered entirely, but one of them, living on a separate property, showed no improvement because it received only the antibiotic application, but was not bathed properly. In both properties there were other horses, but only these three animals presented the skin disease symptoms. Conclusions: The proposed treatment shown to be effective in horses receiving correct application of the prescription, but there is a need for further studies on the epidemiology of equine * Corresponding author: Tel.: +55 31 30240712. E-mail address: [email protected] a Department of Preventive Veterinary Medicine, School of Veterinary, Federal University of Minas Gerais, Av. Antônio Carlos, 6627 - CP 567 - CEP 30123-970 - Belo Horizonte- MG, Brasil. E-mail: [email protected] b EMBRAPA Dairy Cattle c University Presidente Antônio Carlos –UNIPAC skin diseases.