Plasma and blood viscosities, and aggregation of red cells in racehorses.

This research investigates the haemorheologic factors or blood-related factors in racehorses, which might have implications for their overall fitness and performance. The study looks into individual values for viscosity or thickness factors of blood and plasma, rigidity of red cells and more, revealing that it might be possible to characterise individual horses based on these factors.

Study Participants and Metrics

• The subjects of this study are nineteen racehorses. All the horses were studied for various haemorheologic factors or blood-related factors.
• The different factors studied include blood viscosity, plasma viscosity, rigidity of red cells (defined by the term ‘Tk’), haematocrit (the ratio of the volume of red blood cells to the total volume of blood), fibrinogen level (a protein in blood plasma that helps in clotting), and aggregation of red cells.

Findings and Observations

• The study has found that it is possible to characterise individual horses based on their blood viscosity factors and viscosity functions. Specific linear regressions of apparent blood viscosity against log shear rate were found to be particular to individual horses and varied significantly between some horses.
• The data for blood viscosity, plasma viscosity, and haematocrit were almost the same as the values reported for human athletes.
• However, the rigidity and aggregation of red cells were found to be much higher in horses as compared to humans. Aggregation here means the level at which the red cells clump together.
• No significant relation was found between the aggregation of red cells and the level of fibrinogen.
• Erythrocyte sedimentation rates (the rate at which red blood cells settle at the bottom of a test tube in a period of one hour) in blood samples from some horses increased with the decrease of temperature while in others they increased with an increase in temperature.

Implications of the Study

• The research offers insights into the blood-related factors in racehorses that may have implications for their physical fitness and performance.
• Understanding how these factors vary among horses can potentially improve the handling and training of racehorses, as it could provide valuable information to anticipate their response to different physical challenges and how this might impact their health and performance.