ANALYSIS OF BLOOD COMPONENTS IN BLUE-NAPED MOUSEBIRDS UROCOLIUS-MACROURUS

The haematology and the haemoglobin components of 40 captive, adult Bl ue-naped Mousebirds Urocolius macrourus have been studied. Females sho w significantly lower values in the number of erythrocytes, in the abs olute haemoglobin content and in the haematocrit than males. All haema tological parameters (number of erythrocytes and leucocytes, haemoglob in content, haematocrit, MCH, MCHC, glucose, differential count) are w ithin the expected range for birds of this body mass. The blood glucos e (mean value: 202,63+/-50,61mg/dl) shows a clear 24-hour cycle: Durin g the night (174mg/dl) the concentration is 25,7% lower than during th e day (235mg/dl). With respect to the blood parameters, mousebirds are characterized chiefly by two reptile-like features: the erythrocytes of mousebirds are distinctly larger in length (12,95+/-1,23 mu m), wid th (7,12+/-0,75 mu m) and in the volume (132,12+/-20,39 mu m(3)) than those of other birds (see Prinzinger & Misovic 1994). Testing of the h aemoglobin components showed only HbA to be present in all mousebirds tested. HbD, a normal component in most birds, could not be found. Thi s is also a typical feature of crocodiles and suggests a primitive cha racteristic.