BLOOD AND PLASMA VOLUMES IN SHEEP INFECTED WITH TRYPANOSOMA VIVAX

Sheep infected with a West African strain of Trypanosoma vivax showed a reduced packed cell volume, reduced albumin and β-globulin concentrations and an increased γ-globulin concentration. Plasma volume determinations using Evans Blue (T1824) showed that infected sheep had an increased plasma volume, but that the total blood volume remained unaltered. When allowance was made for this increase in plasma volume the intravascular γ-globulin was the only serum protein which was significantly altered in the infected sheep. It is suggested that the increase in γ-globulin which occurs in trypanosomiasis acts as a plasma volume expander and that the fall in the concentration of the other serum proteins is due to dilution. © 1968.