Characterization of the blood volume and iron kinetics in the three-toed sloth, Bradypus tridactylus

Abstract

1. 1. Blood volume and iron kinetics were determined in three specimens of Bradypus tridactylus which were obtained in the coastal north-east regions of Brazil. 2. 2. The average blood volume, circulating red cell volume and plasma volume were 54.9, 19.5 and 35.4 ml/kg body weight, respectively. 3. 3. The average plasma iron disappearance half-time was 150.6min; the red cell radioiron uptake was 62% and the serum iron was 74.3 μg/100 ml. 4. 4. From these figures the plasma iron turnover rate was calculated to be 165.6 μg/kg per day and the red cell iron turnover rate 102.7 μg/kg per day.