Horse Illustrated Magazine

Q: I’ve heard that horses shouldn’t be allowed unlimited grazing when the lush spring grass comes in—that it’s dangerous. How do I safely allow my horse to graze in spring?

A: If your horse is on grass 24/7 while the new spring pastures come in, his digestive system can acclimate gradually as the grass changes. However, if he spends a lot of time in a stall, or the pastures are closed all winter until the grass has come back in really thick and green, then he will need to have more time to get used to it.

The microbes in a horse’s gut that digest forage (hay and pasture) take a long time, at least a week or two, to adjust to new feed sources. Changing suddenly can upset the system, resulting in colic or laminitis, either of which can be fatal in severe cases.

To be on the safe side, start by allowing your horse only 15 minutes a day to graze; you can do this while hand-walking to keep track of time. Each day he can have a little bit more, working up to a few hours per day, and so on. If he tends to gain too much weight from pasture grass, it’s still best to limit his grazing time instead of putting him out on full-time pasture. Excess weight can be bad for his health and cause joint stress. If he must be turned out and you’re worried about his weight, a dry lot or grazing muzzle are good options.

Finally, it’s very important to note that horses with certain metabolic conditions (such as insulin resistance, equine metabolic syndrome or Cushing’s disease) are much more prone to foundering from feed or forage that is too high in starch and sugars. This can include grain, pasture grass or even certain types of hay. Grass containing high levels of sugar isn’t always green, so don’t assume the grass is safe just because it is winter or summer. If you have one of these special needs horses, your veterinarian can help you design a diet that has been tested for low sugar content.

Liked this article? Here are others on spring horse care:
Use Caution When Introducing Horses to Spring Grass
Horse Care Reminders for Spring

This article originally appeared in the April 2014 issue of Horse Illustrated magazine. Click here to subscribe!