Question
I own three Rocky Mountain Horses, all mature, chubby geldings. In the winter, they spend seven or eight hours in a five-acre pasture. Because we get little snowfall and I keep pasture grasses taller in the fall, there’s always some forage for the horses to nibble during those hours, but they do not have access to hay during turnout. In the evening, they come into the barn where they have as much middling grass hay as they like until the next morning. If the weather forecast includes sleet or snow, they remain in the barn for the day. That’s the extent of their diet in the winter. They are dewormed and vaccinated on schedule, and are tended to by the farrier every six weeks. I recently had a conversation with a knowledgeable horsewoman, and she raised her brow at the number of hours my horses went “without” forage. All three horses look robust and dappled, even in their winter coats; all have pleasant dispositions, happy to be at my side. But now I am second-guessing my management. What am I missing?
Answer
The feeding strategy you’ve conceived seems to be working well for you and your horses. From your description of their body condition, the horses are consuming sufficient energy to maintain body weight. On the flip side, the horses may not be consuming all of the nutrients needed for optimal health, which is why many owners choose to feed a vitamin and mineral supplement or ration balancer to horses on all-forage diets. This may be especially prudent in your case, as you describe your hay as middling, which is likely appropriate for your horses from a caloric perspective but not as nutrient-rich as higher quality hay.
Long periods between meals can increase the risk of gastric ulcers, especially if concentrate meals are fed. While your horses may have to work a bit harder for the forage, it is available to them during turnout. The energy required to find that forage—meandering around the pasture, interacting and jostling with herdmates—may actually be beneficial for them as they age, as exercise will help keep joints loose.
Keep an eye on body condition year-round. Overweight horses are thought to be more susceptible to metabolic conditions as they age. The goal should be to maintain horses in moderate body condition, a 5 on the familiar scale that runs from 1 (emaciated) to 9 (obese). Moderate body condition is characterized by ribs that are easily felt but not seen and a flat back that has neither a bony ridge nor a crease.
Rocky Mountain Horses tend to be easy keepers, so obesity is common among members of the breed. Take a hard look at your horses. Are they overweight? Do they have well-developed crests or unusual deposits of fat? If so, you may want to consider different ways to help them slim down, which may include more exercise or more restrictive feeding of forage, no matter the season.
