Quick Answer: to reduce the risk of laminitis you need to restrict your horse's grazing. You can do this by strip grazing, creating a track system or most usual - use a grazing muzzle, preferably a soft one like the LiteBite Horse Muzzle with a grazing slot for a natural bite.
My Horse is Getting Fat, What Can I Do?
Horses are foraging animals who are not ideally suited to today's rich grass available to them all year round. My Connemara pony Skye comes from the west coast of Ireland where the grazing is scrappy and sparse, she had tp search for the grass to get enough to eat, walking all the time. When she came to me she went on to our usual plentiful grazing. She got fat.
I didn't really notice but was brought up short when one day she came in hopping lame, yes it was laminitis and the start of a 9 month nightmare.
Nature intends horses to lose weight over the winter and that gives them a margin when the spring grass comes through, if they are already getting fat they soon become more so, even to the point of being obsese. This is so dangerous.
It is a fact that some horses are fat and don't get laminitis, lucky them, but you just don't know how close yours is to the danger of laminitis so take no risks, keep them slim. Same with us really.
You can restrict their grazing by strip grazing - just move the fence a small amount each day, or can you build a grassless track? Eventually I built one for Skye and now she has no grass at all but once they have had laminitis they are always vulnerable again.
Then there are grazing muzzles, I bought and tried them all but she was miserable and wouldn't eat, that made us both miserable - been there? So I invented the LiteBite grazing muzzle with a slot instead of a little round hole. Success! She wasn't thrilled, none of them love muzzles, but she ate with it.
Do be aware of weight gain and take action right now if this is happening.
All the best, Celie and a slim Skye.