Viscosity and rheologic properties of blood from clinically normal horses.

The research aims to investigate blood viscosity, which measures how thick and sticky the blood is, in clinically healthy horses. They analyze how several factors such as plasma protein and fibrinogen concentration, affect the blood viscosity.

Experimental Method

• The study involved 32 clinically normal horses.
• The viscosity of the blood was measured at varying spindle speeds (60, 30, 12, 6, 3, and 1.5 rpm) and for a Packed Cell Volume (PCV) of 40%, using a digital rotational cone and plate microviscometer. The PCV measures the proportion of blood volume that is occupied by red blood cells, and it essentially reflects the oxygen-carrying capacity of the blood.
• For seven of these horses, the blood viscosity was also taken at different PCV values of 20, 40, and 60%.
• Furthermore, these measures were obtained three times for each of the three PCVs at every spindle speed to understand the effects of changes in PCV on blood viscosity and detect any variations across horses or due to the apparatus.

Assessment of Plasma Protein and Fibrinogen Concentrations

• The total plasma protein and fibrinogen concentrations in the horses’ blood were examined using a standard refractometer for proteins and heat precipitation for fibrinogen, respectively.
• In seven out of the total 32 horses, a quantitative fibrinogen concentration was measured using a unique assay dedicated to this protein.
• The concentrations of plasma protein and fibrinogen in blood samples were evaluated to determine how these factors impact blood viscosity.
• The researchers note that the measured concentrations of plasma total protein (6.0 to 7.5 g/dl) and fibrinogen (100 to 400 mg/dl) fell within the typical reference ranges of their laboratory.