Question
What is your opinion of low-GI feeds? I have grain-sensitive horses and found low-GI feeds did not help as much as promised. Additionally, they seem very high in protein. Is this a concern? Any thoughts would be much appreciated!
Answer
I am curious as to what you mean by “grain-sensitive.” Does he get diarrhea when consuming concentrate feeds, or is it just a question of being more excitable? Or is there another problem that happens when your horses are fed grains?
Feeds that cause a low glycemic response, also called low-GI (glycemic index) feeds, are not totally devoid of grain. Instead, grain is included in much smaller amounts than in a conventional feed and is usually in the form of wheat middlings (the bran, germ, and some residual flour after wheat grain has been processed).
If you take out the starch in a feed, it needs to be replaced with something that does not cause spikes in blood glucose, which could be fiber, fat, or protein sources. Since low-GI feeds are usually targeted to horses that are overweight, they do not need to be calorie-dense, so having them high in fat would not be appropriate. That leaves fiber and protein as possible energy sources. High-fiber feedstuffs are the choice for this type of feed, and typical ingredients include soy hulls, beet pulp, and alfalfa meal because they add calories in a way that does not contribute much to the glycemic index.
Because they are low-intake feeds, they will provide the same amount of vitamins, minerals, and protein in small amounts that fall within the lower recommended feeding rate. In order to provide enough protein, the percentage of protein will be higher but the actual amount that goes into the horse is low because the recommended intake is less than usual. So if the recommended amount is fed, then the amount of protein the product would supply is not significant enough to have an effect in the excitability of the horse or oversupply the horse. If fed well over the recommended feeding rate, a high-protein feed (e.g., 5 lb or 2.3kgs of a 25% protein feed with a recommended feeding rate of 1 lb or 2.2kgs per day) can cause issues because what the body doesn’t use as protein will be broken down to carbohydrate and nitrogen, whereas the carbohydrate can be used for energy production. Following the recommended feeding rates is key to getting the desired results out of a concentrate feed.
If your horse experiences discomfort after eating a grain-based product or even a low-GI feed, you might want to consider using a hindgut buffer like EquiShure to see if it provides some relief.
If your horse is an easy keeper and not in need of the extra calories, he may just need a vitamin/mineral supplement to balance out the all-forage diet, something like our alfalfa-based pellet, Micro-Max or Gold Pellet.
