Pathogenesis of Trypanosoma evansi infection in dogs and horses: hematological and clinical aspects

Abstract

Trypanosoma evansi caused severe anemia in horses and pronounced leukopenia in dogs, both naturally infected. The horses presented microcytic normochromic anemia and the dogs showed microcytic hypochromic anemia. The clinical signs observed were fever, anemia, edema of the legs and lower parts, weakness and inappetence. Light microscopic studies demonstrated that Trypanosoma evansi produced several alterations in erythrocytes of dogs and horses. These pathologic changes included vacuolation, acanthocytes, dacrocytes, codocytes, microspherocytes and bizarre shapes. Mature erythrocyte were observed adhered to trypanosomes. Erythrophagocytosis was also demonstred.