Whole blood, plasma viscosity, and erythrocyte aggregation as a determining factor of competitiveness in standard bred trotters.

The study aims to examine the impact of whole blood and plasma viscosity on exercise endurance during low intensity training, comparing experienced and novice standardbred trotters. The researchers found that both blood viscosity and erythrocyte aggregation increased significantly during exercise, but decreased back to normal levels after a 30-minute rest period. The results also indicate that trained horses experienced more pronounced changes in blood fluidity than their untrained counterparts.

Research Objective

• The primary aim of this research was to analyze whether whole blood and plasma viscosity influence the ability of horses to tolerate exercise during submaximal training. The research further attempted to distinguish any differences in these blood properties between trained and untrained standardbred trotters.

Methodology

• The study involved 42 healthy adult trotters – 20 at the start of their training and 22 already well-trained horses.
• Venous blood samples were collected from the trotters before, immediately after, and 30 minutes after submaximal exercise.
• Whole blood viscosity, plasma viscosity, and erythrocyte aggregation were measured, alongside other exercise-relevant variables such as heart rate, oxygen saturation, and lactate levels.

Results

• The research found that both whole blood viscosity and plasma viscosity significantly increased at all shear rates during exercise, but returned to normal after a 30-minute rest period.
• In contrast, researchers found no changes in whole blood viscosity in the hematocrit standardized samples.
• Erythrocyte aggregation (or, red blood cell clumping) indices also increased after exercise.
• Other fitness-related factors increased during the race, including creatin-kinase (a muscle enzyme), lactate (a chemical produced during intense exercise), hemoglobine (protein in red blood cells), heart rate, and oxygen saturation. In contrast, PH (a measure of acidity) and BE (base excess, related to the body’s buffering capacity) levels decreased during the run.
• The study also found that exercise triggered more extensive changes in blood fluidity in well-trained horses compared to inexperienced ones. This difference was especially pronounced for low shear whole blood viscosity and erythrocyte aggregation.

Conclusions

• Over the course of this study, the researchers were able to show that low intensity exercise leads to noticeable changes in key blood properties in standardbred trotters, including increased whole blood and plasma viscosity and erythrocyte aggregation.
• Interestingly, the research also revealed that these changes in blood fluidity were more pronounced in trained horses compared to their untrained counterparts. This could indicate that the bodies of trained horses have adapted to handle intense physical activity, possibly by changing the properties of their blood to enable better oxygen supply or quicker cooling.