ABSTRACT
Trypanosoma are extra-erythrocytic, protozoan parasites of domestic and wild animals. It is transmitted by biting flies and a cause of fever, anemia, myocarditis and corneal opacity. In the present study, Trypanosoma infection is reported in a male bull dog of two years age at Lahore, Pakistan. Clinical signs and symptoms of infection are recorded. Confirmation of case was done by microscopic examination of Trypanosoma organism in thick blood smear. Furthermore, their effect on certain hematological parameters was studied and concluded that there was decrease of hemoglobin [Hb] concentration and packed cell volume [PCV] while erythrocytes sedimentation rate [ESR] was increased in the infected dog. The animal was successfully treated with single dose of diminazene diaceturate at the dose rate of 3.5 mg/kg body weight, intramuscularly alongwith the supportive therapy