Horses need forage, period
If grass is sparse or unavailable free choice hay should be given. Horses are hind gut fermenters. They require roughage in their hind gut at all times for their health and mental well being. Energy comes from the hind gut. Now I’m sure you’re thinking what’s the connection between the stomach and mental health.
There are several signs that your horse may not be getting enough grass/hay. Loss of weight is obvious, but not always the case. If your horse is getting enough grain and lacks work, he’ll be able to maintain his weight. Is your normally quite horse nervous? Is your nervous horse more high strung than usual? Lack of forage (an empty or nearly empty hind gut) causes horses to worry. Worry leads to ulcers, stress and poor mental and physical health. Are your wooden fences being chewed? It could indicate boredom or not enough hay. Do they stand around in the pasture, not grazing? Hind gut fermentation is also your horse’s furnace and provides warmth. If your horse is loosing weight in the winter, chances are he’s cold and not getting enough hay.
I accidentally found out my own horse was’t getting enough hay a few years ago. It was a tough winter and we weren’t spending much time at the barn, let alone riding. My horse at the time was very up in the winter, got the spring crazies for a few weeks and was very laid back in summer and fall. Spring finally came, the snow melted and we were able to get out on the trails again. He was spooky and nervous. I attributed it to spring crazies. A few weeks went by and he hadn’t changed. He’s normally a pig, but the constant grass diving was making me crazy. As we walked down a fence line, he tried eating the fence. I knew something was wrong. We immediately went back to the barn to ask what was going on. We were told by the barn worker that she was told to stop giving hay since there was grass. Unfortunately there was no grass. The “grass” was non eatable weeds. While talking to other boarders, their horses were the same way. Most were standing in the pasture eating the fence. When we politely addressed this with the owner, she lost her temper and denied it. Need less to say, we moved.