Hematology of Wild Allied Rock-Wallabies, Petrogale-Assimilis Ramsay, 1877 (Marsupialia, Macropodidae), in North Queensland

Abstract

The haematology of a colony of wild allied rock-wallabies, Petrogale assimilis Ramsay, 1877, from north-western Queensland was studied for 20 months. Wallabies were repeatedly trapped at monthly intervals and 511 blood samples from 96 animals were examined, making this the most comprehensive study of the haematology of any macropod species. The morphology of the red blood cells and leucocytes was similar to those of other marsupials. Large and small lymphocytes were recognised. Binucleate lymphocytes were found in 7.2% of blood smears. Normal haematological values were within the published ranges for other marsupials. However, the average white blood cell count (mean +/- s.e.: 9.03 +/- 0.92 X 10(9) L-1) was close to the upper end of the range for macropods. The normal (mean +/- s.e.) red blood cell count (5.24 + 0.15 X 10(12) L-1), packed cell volume (0.4291 +/- 0.019 L L-1) and haemoglobin concentration (14.07 +/- 0.41 g dL-1) of male wallabies were higher than those of females (4.79 +/- 0.15 X 10(12) L-1, 0.3952 +/- 1.19 L L-1, and 12.95 +/- 0.41 g dL-1, respectively). No gender differences were detected in the white blood cell count (9.03 +/- 0.92 x 10(9) L-1), mean corpuscular volume (82.28 +/- 1.35 fL), mean corpuscular haemoglobin (26.98 +/- 0.57 pg) or mean corpuscular haemoglobin concentration (32.82 +/- 0.57 g L 1). The red blood cell count, packed cell volume, haemoglobin concentration, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration and the absolute neutrophil count in juveniles and subadults increased with age. The neutrophil to lymphocyte ratio was less than 1.0 in pouch young and approached 1.0 in adults. The red blood cell count, packed cell volume and haemoglobin concentration of lactating females did not vary with age of pounch young.