The effect of Babesia canis induced haemolysis on the canine haemoglobin oxygen dissociation curve.

Samples of blood from normal healthy (n = 7) and Babesia canis-infected dogs (n = 7) were subjected to varying oxygen tensions in a tonometer, after which the samples were subjected to blood gas analysis and haemoximetry. This data was used to plot haemoglobin oxygen dissociation curves (ODC) for both groups of dogs. States of acidosis and hypercapnia were then simulated by modelling, and the response of the 2 haemoglobin oxygen dissociation curves compared. The ODC of the B. canis-infected group showed a decreased ability to shift to the right when compared to that of the normal, healthy ODC. This decreased Bohr effect probably exacerbates the severe tissue hypoxia associated with this disease by impairing the ability of haemoglobin to off-load oxygen at the tissue level.