Using red blood cell creatine concentration to evaluate the equine erythropoietic response.

This research studied the concentration of creatine in red blood cells (RBCs) of horses to understand its relation with the production of new blood cells, or erythropoiesis. Different populations of horses, including healthy and anemic ones, were examined and findings suggest that RBC creatine concentration can serve as an indicator of the equine erythropoietic response.

Research Study and Findings

• Researchers investigated the association between red blood cell (RBC) creatine concentration and the body’s process of producing new red blood cells (erythropoiesis) in horses.
• Different groups of subjects including 9 healthy horses, 4 healthy ponies, 24 anemic horses, and 2 horses with artificially induced anemia were involved for this study.
• To measure the RBC creatine concentration, researchers used a technique called a modified Jaffe reaction.
• The average RBC creatine concentration in healthy horses was found to be 5.72 +/- 0.42 mg/dl. For healthy ponies, it was 2.59 +/- 0.31 mg/dl.
• When examining the blood cells of healthy horses, it was revealed that the young RBC populations had significantly higher creatine content (7.72 +/- 0.57 mg/dl) as compared to the older RBC populations (4.03 +/- 0.27 mg/dl).
• The study also included anemically affected horses. Out of them, 12 with a packed cell volume (PCV) between 25% and 30% had an average RBC creatine concentration of 6.12 +/- 0.46 mg/dl while 7 other anemic horses with PCV less than 25% had a mean RBC creatine value of 6.07 +/- 0.12 mg/dl.
• Researchers also observed the bone marrow of 5 anemic horses and the 2 horses in which anemia was artificially induced. The results showed a positive correlation between the RBC creatine concentration and the count of immature red blood cells or reticulocytes.
• A negative correlation was found between the RBC creatine concentration and the ratio of myeloid to erythroid cells, indicating that higher RBC creatine levels are associated with a reduced relative number of myeloid cells (a type of white blood cell) compared to erythroid cells (red blood cell precursors).

Implication of the Research

• This study provides a significant insight into erythropoiesis in equine species, suggesting that RBC creatine concentration can serve as an indicator of this process.
• The finding that RBC creatine concentration correlates positively with reticulocyte count further strengthens the assumption that high creatine levels could indicate an active erythropoietic response, i.e., production and maturation of new red blood cells.
• The negative correlation found between the RBC creatine concentration and the myeloid-erythroid ratio could further imply different stages or speed of erythropoiesis in the horses.