Blood glucose in the horse at rest and exercise

This paper reviews different aspects affecting equine blood glucose concentration and contrasts them with those in man. The effects of feeding, exercise and disease on blood glucose are also discussed. Glucose is an energy substrate for all cells and the principal fuel for the brain. Maintenance of glucose supply to working skeletal muscle from muscle glycogen and blood glucose is critical to sustain work output during exercise. Glucose metabolism has been intensively studied in human athletes due to the crucial roles of muscle glycogen stores and blood glucose. The changes in equine blood glucose concentration are qualitatively very similar to those in humans. However, regardless of many similarities, the results of such human studies cannot be directly applied to horses, because different animal species are specifically adapted to meet their own unique requirements. It is known that horses do have many species specific-features in their carbohydrate metabolism which are still incompletely understood. Further research is needed both in healthy horses and in horses with disturbances in their carbohydrate metabolism to give a more comprehensive understanding of metabolic responses and regulation in horses.