Patterns of variation in vertebrate haematology

Abstract

In the absence of species-specific haematological reference data for the vast majority of vertebrate species, a broad comparative approach is of value because it allows general patterns of variation to be identified. This paper presents a broad overview of qualitative and quantitative variation in avian and mammalian haematological characteristics. Morphological differences are most apparent in the erythrocytes and haemostatic cells of vertebrates. Some quantitative parameters, such as red cell number (RBC) and red cell size (MCV) vary widely among species whereas others, such as haemoglobin concentration (Hb), packed cell volume (PCV) and mean cell haemoglobin concentration (MCHC) vary little. These findings may have implications for understanding variation in haemorheological properties of different species. The results also provide guidelines for clinical interpretation in species for which reference data are not available.