BLOOD OF BIRDS - AN ALLOMETRIC REVIEW OF ITS COMPONENTS

In this review the allometric relations of different blood parameters to body mass in birds are given. The following parameters are treated: physical and chemical properties, leucocytes (number, differential bl ood count, Arneth counts, ontogeny), erythrocytes (number, length, wid th, volume, hemoglobin content, ontogeny, different forms during embry ogeny, maturation), blood glucose, hematocrit, hemoglobin, MCV, MCH, M CHC, plasma protein concentration, thrombocytes (number, ontogeny) and blood groups. The influence of different endogenous (sex, hormones, a ge, laying cycle, breeding, etc.) and exogenous factors (temperature, activity, diurnal cycle, geographical altitude, climate, etc.) is disc ussed. The taxonomic differentiation in different systematic orders wi thin the birds is presented. Compared to mammalia only very few differ ences characterize bird blood: The oval erythrocytes are nucleated, bl ood glucose level is twice as high, plasma protein content is consider ably lower and the (nucleated) thrombocytes are as big as the other le ucocytes.