Answer

By Your Horse

Nutritionist Lizzie Drury says:

Grass or ‘gassy’ colic is believed to occur when the microbes in the colon produce excessive gas, perhaps due to dietary changes or fermentable feeds.
You’ve identified that your pony is particularly vulnerable in the summer, which means there may be a small window of opportunity to prepare for this and help to prevent it. The first thing I’d suggest is to gradually increase her turnout time from the end of the winter onwards, so that she’s not suddenly exposed to full-time grass turnout when the summer arrives. This will give her digestive system time to gradually adapt to the decrease in dry matter intake and the increase in grass.Grass is highly fermentable so it’s easy for the microbes to rapidly digest this, producing volatile fatty acids and gas bubbles. The movement and contractions of the digestive tract, and access to sources of less rapidly fermentable fibres such as hay, help to carry the passage of these gas bubbles through and out of the hindgut. I would advise that you provide additional forage in the form of hay in your horse’s field. Since your Shetland appears to be very sensitive to the fermentation process, you may also find that the strategic use of a hindgut buffer, such as Kentucky Equine Research’s EquiShure, may help.