Leucocyte and thrombocyte responses in dogs experimentally infected with Trypanosoma brucei.

Three dogs were subcutaneously infected with Trypanosoma brucei strain ILRAD 1797. Artificial haemolytic anaemia was induced in 2 other dogs by phlebotomy, heat treatment and re-infusion of the blood, while 2 dogs were kept as control animals. The infected animals developed pan-leucopenia and thrombocytopenia, while the dogs with artificial haemolytic anaemia developed leucocytosis and thrombocytosis. These findings suggest that there was a bone marrow depressing factor in the plasma of T. brucei-infected dogs especially as it affected leucocyte production.