In this article we show in the Scarlet Rosefinch (Carpodacus erythrinus) that haematological parameters other than the widely used heterophil/lymphocyte (H/L) ratio may be important to investigate in birds. We give the full description of seven basic haematological traits.
Most remarkably, we revealed that this species has an extraordinarily high proportion of basophils among the peripheral blood leukocytes (on average about 42 and 56%, respectively). Although the high basophil count is a general trait even in healthy individuals of this species, the proportion of these cells is condition-dependent and is further increased by Haemoproteus infection.
Our results also suggest that the immature erythrocyte count in the peripheral blood is a good predictor of the nestlings’ growth rate. The Rosefinch haematology differs strikingly from other avian species with known values of basic haematological parameters.