Skin. Leishmania (L.) chagasi-naturally infected (A, C, D, E, F) and non-infected dog (B). A) Absence of amastigotes in skin of the ear of asymptomatic dog; B) Absence of amastigotes in skin of the ear of control dog. C) Presence of few amastigotes in skin with minimal inflammatory infiltrate. D) Minimal inflammatory infiltrate constituted by lymphocytes, plasma cells and macrophages. E) Presence of many parasites in skin with severe inflammation. F) Severe inflammatory infiltrate constituted by macrophages and neutrophils. Imunoperoxidase staining (A, B, C, E). H-E staining (D, F). Original magnifications: ×140.