Abstract:
This prospective longitudinal study investigated the progression of haematological
changes in 32 transfused and 54 non-transfused dogs naturally infected with Babesia rossi
over the 1st 6 days following diagnosis and treatment. The effect of patient age on the
results of complete blood counts was determined. Haematology data were analysed at
presentation and at 24 hours, 3 days and 6 days after presentation. Dogs were treated with
diminazene aceturate at diagnosis and a blood transfusion was given if deemed clinically
required. Mildly to moderately regenerative normocytic normochromic anaemia was
observed in all dogs throughout the study period. Transfused dogs more often had an
inflammatory leukogram at presentation and at 24 hours, than dogs that were not transfused.
In dogs with a left shift, a concurrent normal or decreased segmented neutrophil
count was found more commonly than neutrophilia. Severe thrombocytopenia that
resolved within a week was common. Blood transfusion alleviated the anaemia, but had no
significant effect on white blood cell or platelet responses. Blood cell responses were not
significantly influenced by age. In conclusion, the red blood cell and white blood cell
responses were less than expected in dogs with babesiosis, given the degree of anaemia and
inflammation present. The magnitude of thrombocytopenia and rapid return of the
platelet count to normal suggested a possible immune-mediated mechanism for the
thrombocytopenia.
