The Effects of Nonstructural Carbohydrate Content and Feeding Rate on Glucose and Insulin Response to Meal Feeding in Equine

The following research encompassed two experiments and involved feeding horses two isocaloric diets (diet A and diet B), with an approximate 50% difference in nonstructural carbohydrate (NSC) content. There were three main objectives: first, to test the hypothesis that feeding an approximately 50% lower NSC concentrate feed would cause a lower glucose and insulin response; second, to test the hypothesis that feeding meals equal in NSC content would create similar responses in glucose and insulin dynamics; and finally, to test the hypothesis that the time spent eating is correlated with glucose/insulin response. In experiment 1, in which diet A and diet B were fed at the same rate, the main finding was that feeding a meal lower in NSC resulted in a lower glucose and insulin response to the feed. In experiment 2, in which the effects of feeding diets A and B at a rate to provide 0.3 g/kg body weight (BW) NSC per meal were explored, the main finding was that, although glucose responses were similar, the meal containing more NSC/kg and fed at the lower rate resulted in a substantially lower insulin response. Consumption time also was found to be significantly different between treatments.In conclusion, a low NSC formulation and small meal size appear to be sensible recommendations for horses that may benefit from a low glucose and insulin response to feeding. In addition to NSC content, meal size, and nutrient:calorie ratio, nutrient requirements of the individual horse and the entire nutritional balance of the diet also should be addressed.