Effect of gender and exercise on haematological and biochemical parameters in Holsteiner horses.
Authors: Andriichuk A, Tkachenko H
Journal: Journal of animal physiology and animal nutrition
Summary
# Editorial Summary Holsteiner stallions and mares aged six years responded distinctly to moderate-intensity exercise, with stallions demonstrating pronounced haematological shifts including elevated leucocyte and granulocyte counts alongside increases in erythrocyte mass, haemoglobin and haematocrit—findings consistent with enhanced oxygen delivery capacity during exertion—whilst mares exhibited a selective decrease in platelet volume post-exercise. Biochemically, exercise-induced elevations in aspartate aminotransferase activity were significant only in stallions, suggesting either greater muscular effort or differential metabolic responses between sexes, though both sexes demonstrated beneficial reductions in lipid peroxidation after training, indicating adaptive antioxidant responses. Interestingly, stallions showed exercise-induced increases in oxidative-modified erythrocyte proteins despite unchanged erythrocyte osmotic fragility between sexes and conditions, implying that oxidative stress markers may not necessarily translate to compromised red cell integrity. For practitioners, these findings underscore the importance of establishing sex-specific baseline haematological and biochemical parameters when assessing fitness responses and recovery in sport horses, particularly regarding enzyme markers in stallions, which may aid in tailoring conditioning programmes and identifying overtraining without relying solely on erythrocyte fragility as a stress indicator.
Read the full abstract on PubMed
Practical Takeaways
- •Gender differences exist in haematological responses to exercise in horses; stallions demonstrate more pronounced increases in red blood cell parameters and liver enzyme activity than mares
- •Exercise-induced oxidative stress occurs in both sexes but manifests differently; monitor for oxidative stress markers particularly in stallions during training programs
- •Platelet volume changes in mares after exercise may warrant monitoring during conditioning, though erythrocyte resistance to acid was similar between sexes
Key Findings
- •Stallions showed significant increases in leucocytes, granulocytes, erythrocytes, haemoglobin and haematocrit after exercise, while mares showed significant decrease in platelet volume
- •Pre-exercise mean corpuscular haemoglobin concentration was higher in stallions compared to mares
- •Exercise induced significant increase in aspartate aminotransferase activity in stallions only
- •Trained mares and stallions showed decreased lipid peroxidation after exercise, but stallions demonstrated exercise-induced oxidative stress indicated by increased oxidative modified protein of erythrocytes